diff --git a/src/h5_core/h5_core_private.h b/src/h5_core/h5_core_private.h
index 763f98f..dcf99a6 100644
--- a/src/h5_core/h5_core_private.h
+++ b/src/h5_core/h5_core_private.h
@@ -91,7 +91,7 @@
 	(  entity_id & H5T_ELEM_MASK )
 
 #define TRY( func )					\
-	if ( (int64_t)(ptrdiff_t)(func) < (int64_t)0 )	\
+	if ( (int64_t)(ptrdiff_t)(func) <= (int64_t)H5_ERR )	\
 		return H5_ERR;
 
 /*!
diff --git a/src/h5_core/h5t_adjacencies.c b/src/h5_core/h5t_adjacencies.c
index b86f3fe..950dbca 100644
--- a/src/h5_core/h5t_adjacencies.c
+++ b/src/h5_core/h5t_adjacencies.c
@@ -18,6 +18,33 @@
 #include "h5_core/h5_core.h"
 #include "h5_core/h5_core_private.h"
 
+h5_id_t *
+_h5t_get_edge_of_tet (
+	const h5_elem_ldta_t *tet,
+	const h5_id_t face_id,
+	h5_2id_t edge
+	) {
+	int map[6][2] = { { 0,1 }, {1,2}, {0,2}, {0,3}, {1,3}, {2,3} };
+
+ 	edge[0] = tet->local_vids[map[face_id][0]];
+	edge[1] = tet->local_vids[map[face_id][1]];
+	return edge;
+}
+
+h5_id_t *
+_h5t_get_triangle_of_tet (
+	const h5_elem_ldta_t *tet,
+	const h5_id_t face_id,
+	h5_2id_t tri
+	) {
+	int map[4][3] = { { 1, 2, 3 }, { 0, 2, 3 }, { 0, 1, 3 }, { 0, 1, 2} };
+	
+ 	tri[0] = tet->local_vids[map[face_id][0]];
+	tri[1] = tet->local_vids[map[face_id][1]];
+	tri[2] = tet->local_vids[map[face_id][2]];
+	return tri;
+}
+
 
 /*
   compute T(V)
@@ -27,13 +54,13 @@ _calc_tets_of_vertices (
 	h5_file_t * const f
 	) {
 	h5t_fdata_t *t = f->t;
-	h5_tet_data_t *tet;
+	h5_elem_ldta_t *tet;
 
 	h5_id_t local_tid;
 	h5_id_t local_vid;
 	int i;
 
-	for ( local_tid = 0, tet = &t->elems_data.tets[0];
+	for ( local_tid = 0, tet = &t->elems_ldta[0];
 	      local_tid < t->num_elems[t->num_levels-1];
 	      local_tid++, tet++ ) {
 		for ( i = 0; i < 4; i++ ) {
@@ -77,7 +104,7 @@ _search_te2 (
 	h5t_adjacencies_t *a = &t->adjacencies;
 	void *vnode;
 
-	h5_tet_data_t *tet_data = &t->elems_data.tets[local_eid];
+	h5_elem_ldta_t *tet_data = &t->elems_ldta[local_eid];
 	h5_id_t vid;
 	int map[6][2] = { { 0,1 }, {1,2}, {0,2}, {0,3}, {1,3}, {2,3} };
 
@@ -109,8 +136,8 @@ _search_te2 (
 	return H5_SUCCESS;
 }
 
-static h5_err_t
-_find_te (
+h5_err_t
+_h5t_find_te (
 	h5_file_t * const f,
 	h5_te_node_t **rnode,
 	h5_2id_t edge
@@ -146,7 +173,7 @@ _h5t_find_te2 (
 	h5_te_node_t node;
 	void *vnode = &node;
 
-	h5_tet_data_t *tet_data = &t->elems_data.tets[local_eid];
+	h5_elem_ldta_t *tet_data = &t->elems_ldta[local_eid];
 	h5_id_t *edge = node.key.vids;
 	int map[6][2] = { { 0,1 }, {1,2}, {0,2}, {0,3}, {1,3}, {2,3} };
 
@@ -197,7 +224,7 @@ _calc_tets_of_edges (
 	h5_id_t local_eid;
 	h5_size_t num_tets = t->num_elems[t->num_levels-1];
 	h5_te_node_t *node = NULL;
-	h5_tet_data_t *tet = &t->elems_data.tets[0];
+	h5_elem_ldta_t *tet = &t->elems_ldta[0];
 	h5_id_t face_id;
 
 	a->te_tree = NULL;
@@ -254,7 +281,7 @@ _search_td2 (
 	h5t_adjacencies_t *a = &t->adjacencies;
 	void *vnode;
 
-	h5_tet_data_t *tet_data = &t->elems_data.tets[local_eid];
+	h5_elem_ldta_t *tet_data = &t->elems_ldta[local_eid];
 	h5_id_t vid;
 	int map[4][3] = { { 1,2,3 }, {0,2,3}, {0,1,3}, {0,1,2} };
 
@@ -293,22 +320,8 @@ _search_td2 (
 	return H5_SUCCESS;
 }
 
-h5_id_t *
-_h5t_get_triangle_of_tet (
-	const h5_tet_data_t *tet,
-	const h5_id_t face_id,
-	h5_2id_t tri
-	) {
-	int map[4][3] = { { 1, 2, 3 }, { 0, 2, 3 }, { 0, 1, 3 }, { 0, 1, 2} };
-	
- 	tri[0] = tet->local_vids[map[face_id][0]];
-	tri[1] = tet->local_vids[map[face_id][1]];
-	tri[2] = tet->local_vids[map[face_id][2]];
-	return tri;
-}
-
-static h5_err_t
-_find_td (
+h5_err_t
+_h5t_find_td (
 	h5_file_t * const f,
 	h5_td_node_t **rnode,
 	h5_3id_t tri
@@ -329,18 +342,22 @@ _find_td (
 		vid = tri[0]; tri[0] = tri[1]; tri[1] = vid;
 	}
 	memcpy ( node.key.vids, tri, 3*sizeof(*tri) );
-	TRY ( vnode = _h5_tfind (
+	vnode = _h5_tfind (
 		      f,
 		      vnode,
 		      (void**)&a->td_tree,
-		      _cmp_td_node ) );
+		      _cmp_td_node );
+	if ( (h5_err_t)(ptrdiff_t)(vnode) == H5_ERR ) {
+		return _h5t_error_local_triangle_nexist( f, tri );
+	}
+
 	*rnode = *(h5_td_node_t **)vnode;
 
 	return H5_SUCCESS;
 }
 
-static h5_err_t
-_find_td2 (
+h5_err_t
+_h5t_find_td2 (
 	h5_file_t * const f,
 	h5_td_node_t **rnode,
 	h5_id_t face_id,
@@ -351,7 +368,7 @@ _find_td2 (
 	h5_td_node_t node;
 	void *vnode = &node;
 
-	h5_tet_data_t *tet_data = &t->elems_data.tets[local_eid];
+	h5_elem_ldta_t *tet_data = &t->elems_ldta[local_eid];
 	h5_id_t *tri = node.key.vids;
 
 	_h5t_get_triangle_of_tet ( tet_data, face_id, tri );
@@ -366,11 +383,15 @@ _find_td2 (
 	if ( tri[0] > tri[1] ) {
 		vid = tri[0]; tri[0] = tri[1]; tri[1] = vid;
 	}
-	TRY ( vnode = _h5_tfind (
-		      f,
-		      vnode,
-		      (void**)&a->td_tree,
-		      _cmp_td_node ) );
+	vnode = _h5_tfind (
+		f,
+		vnode,
+		(void**)&a->td_tree,
+		_cmp_td_node );
+	if ( (h5_err_t)(ptrdiff_t)(vnode) == H5_ERR ) {
+		return _h5t_error_local_triangle_nexist( f, tri );
+	}
+
 	*rnode = *(h5_td_node_t **)vnode;
 
 	return H5_SUCCESS;
@@ -408,7 +429,7 @@ _calc_tets_of_triangles (
 	h5_id_t local_eid;
 	h5_size_t num_tets = t->num_elems[t->num_levels-1];
 	h5_td_node_t *node = NULL;
-	h5_tet_data_t *tet = &t->elems_data.tets[0];
+	h5_elem_ldta_t *tet = &t->elems_ldta[0];
 	h5_id_t face_id;
 
 	a->td_tree = NULL;
@@ -453,50 +474,21 @@ _h5t_rebuild_adj_data (
 h5_err_t
 _compute_direct_children_of_edge (
 	h5_file_t * const f,
-	h5_id_t local_kid,
+	h5_id_t face_id,
 	h5_id_t local_eid,
 	h5_id_t	kids[2]
 	) {
-	h5_id_t face_id = _h5t_get_face_id ( local_kid );
+	int off[6][2] = { {0,1}, {1,2}, {0,2}, {0,3}, {1,3}, {2,3} };
 
-	if ( face_id == 0 ) {
-		kids[0] = _h5t_build_edge_id ( 0, local_eid+0 );
-		kids[1] = _h5t_build_edge_id ( 0, local_eid+1 );
-	} else if ( face_id == 1 ) {
-		kids[0] = _h5t_build_edge_id ( 1, local_eid+1 );
-		kids[1] = _h5t_build_edge_id ( 1, local_eid+2 );
-	} else if ( face_id == 2 ) {
-		kids[0] = _h5t_build_edge_id ( 2, local_eid+0 );
-		kids[1] = _h5t_build_edge_id ( 2, local_eid+2 );
-	} else if ( face_id == 3 ) {
-		kids[0] = _h5t_build_edge_id ( 3, local_eid+0 );
-		kids[1] = _h5t_build_edge_id ( 3, local_eid+3 );
-	} else if ( face_id == 4 ) {
-		kids[0] = _h5t_build_edge_id ( 4, local_eid+1 );
-		kids[1] = _h5t_build_edge_id ( 4, local_eid+3 );
-	} else if ( face_id == 5 ) {
-		kids[0] = _h5t_build_edge_id ( 5, local_eid+2 );
-		kids[1] = _h5t_build_edge_id ( 5, local_eid+3 );
-	} else {
+	if ( ( face_id < 0 ) || ( face_id >= 6 ) ) {
 		return  h5_error_internal ( f, __FILE__, __func__, __LINE__ ); 
 	}
+	kids[0] = _h5t_build_edge_id ( face_id, local_eid+off[face_id][0] );
+	kids[1] = _h5t_build_edge_id ( face_id, local_eid+off[face_id][1] );
 	return H5_SUCCESS;
 }
 
-/*
-def _compute_children_of_edge ( E, children ):
-	for E' = in =T(E):
-		T' = tetrahedron bound to E'
-		if T' has no children on level ≤ L: next
-		(E'0, E'1) = _compute_direct_children_of edge ( E' )
-		for i in [0,1]:
-			T'i = tetrahedron bound to D'i
-			if T'i has children on level ≤ L:
-				_compute_children_of_edge ( E'i, children )
-			else:
-				children.append ( E'i ) 
-*/
-h5_err_t
+static h5_err_t
 _compute_children_of_edge (
 	h5_file_t * const f,
 	h5_id_t local_kid,
@@ -504,7 +496,6 @@ _compute_children_of_edge (
 	) {
 	h5t_fdata_t *t = f->t;
 	h5_te_node_t *te;
-	int i,k;
 
 	TRY ( _h5t_find_te2 (
 		      f,
@@ -512,93 +503,96 @@ _compute_children_of_edge (
 		      _h5t_get_face_id ( local_kid ),
 		      _h5t_get_elem_id ( local_kid ) ) 
 		);
-	for ( k = 0; k < te->value.num_items; k++ ) {
-		h5_id_t local_eid = _h5t_get_elem_id ( te->value.items[k] );
-		h5_tet_data_t *tet = &t->elems_data.tets[local_eid];
-
-		/* no children? */
-		if ( tet->local_child_eid < 0 )
-			continue;
-		/* no children on current level? */
-		h5_tet_data_t *child_tet = &t->elems_data.tets[tet->local_child_eid];
-		if ( child_tet->level_id > t->cur_level )
-			continue;
-
-		h5_id_t local_kids[2];
-		TRY ( _compute_direct_children_of_edge (
-			f,
-			te->value.items[k],	/* parent edge */
-			tet->local_child_eid,	/* first children of element */
-			local_kids ) );		/* result */
-		for ( i = 0; i < 2; i++ ) {
-			local_eid = _h5t_get_elem_id ( local_kids[i] );
-			tet = &t->elems_data.tets[local_eid];
-
-			/* no children? */
-			h5_id_t l_chld_eid = tet->local_child_eid;
-			if ( ( l_chld_eid < 0 ) ||
-			     ( t->elems_data.tets[l_chld_eid].level_id > t->cur_level)) {
-				TRY ( _h5_append_to_idlist (
-					      f, children, local_kids[i] )
-					);
-			} else {
-				TRY ( _compute_children_of_edge (
-					      f, local_kids[i], children ) );
-			}
+	h5_id_t *edge = te->value.items;
+	h5_id_t *end = te->value.items+te->value.num_items;
+	for ( ; edge < end; edge++ ) {
+		h5_id_t local_eid = _h5t_get_elem_id ( *edge );
+		h5_id_t face_id =  _h5t_get_face_id ( *edge );
+		h5_elem_ldta_t *tet = &t->elems_ldta[local_eid];
+		if ( _h5t_elem_is_on_cur_level ( f, tet ) == H5_OK ) {
+			TRY ( _h5_append_to_idlist (
+				      f, children, *edge )
+				);
+		} else {
+			h5_id_t local_kids[2];
+			TRY ( _compute_direct_children_of_edge (
+				      f,
+				      face_id,
+				      tet->local_child_eid,
+				      local_kids ) );
+			TRY ( _compute_children_of_edge (
+				      f, local_kids[0], children ) );
+			TRY ( _compute_children_of_edge (
+				      f, local_kids[1], children ) );
 		}
 	}
 	return H5_SUCCESS;
 }
 
-
-h5_err_t
-_compute_direct_children_of_triangle (
+/* 
+   Compute all sections of an edge.
+*/
+static h5_err_t
+_compute_sections_of_edge (
 	h5_file_t * const f,
-	h5_id_t local_did,
-	h5_id_t	children_dids[4]
+	h5_id_t local_kid,
+	h5_idlist_t *children
 	) {
+	h5t_fdata_t *t = f->t;
+	h5_te_node_t *te;
 
-	h5_id_t local_eid = _h5t_get_elem_id ( local_did );
-	h5_id_t face_id = _h5t_get_face_id ( local_did );
-	if ( face_id == 0 ) {
-		children_dids[0] = _h5t_build_triangle_id ( 0, local_eid+1 );
-		children_dids[1] = _h5t_build_triangle_id ( 0, local_eid+2 );
-		children_dids[2] = _h5t_build_triangle_id ( 0, local_eid+3 );
-		children_dids[3] = _h5t_build_triangle_id ( 0, local_eid+7 );
-	} else if ( face_id == 1 ) {
-		children_dids[0] = _h5t_build_triangle_id ( 1, local_eid+0 );
-		children_dids[1] = _h5t_build_triangle_id ( 1, local_eid+2 );
-		children_dids[2] = _h5t_build_triangle_id ( 1, local_eid+3 );
-		children_dids[3] = _h5t_build_triangle_id ( 1, local_eid+6 );
-	} else if ( face_id == 2 ) {
-		children_dids[0] = _h5t_build_triangle_id ( 2, local_eid+0 );
-		children_dids[1] = _h5t_build_triangle_id ( 2, local_eid+1 );
-		children_dids[2] = _h5t_build_triangle_id ( 2, local_eid+3 );
-		children_dids[3] = _h5t_build_triangle_id ( 2, local_eid+4 );
-	} else if ( face_id == 3 ) {
-		children_dids[0] = _h5t_build_triangle_id ( 3, local_eid+0 );
-		children_dids[1] = _h5t_build_triangle_id ( 3, local_eid+1 );
-		children_dids[2] = _h5t_build_triangle_id ( 3, local_eid+2 );
-		children_dids[3] = _h5t_build_triangle_id ( 3, local_eid+5 );
-	} else {
-		return  h5_error_internal ( f, __FILE__, __func__, __LINE__ ); 
+	TRY ( _h5t_find_te2 (
+		      f,
+		      &te,
+		      _h5t_get_face_id ( local_kid ),
+		      _h5t_get_elem_id ( local_kid ) ) 
+		);
+	h5_id_t *edge = te->value.items;
+	h5_id_t *end = te->value.items+te->value.num_items;
+	int refined = 0;
+	for ( ; edge < end; edge++ ) {
+		h5_id_t local_eid = _h5t_get_elem_id ( *edge );
+		h5_id_t face_id =  _h5t_get_face_id ( *edge );
+		h5_elem_ldta_t *tet = &t->elems_ldta[local_eid];
+		if ( ! _h5t_elem_is_on_cur_level ( f, tet ) == H5_OK ) {
+			refined = 1;
+			h5_id_t local_kids[2];
+			TRY ( _compute_direct_children_of_edge (
+				      f,
+				      face_id,
+				      tet->local_child_eid,
+				      local_kids ) );
+			TRY ( _compute_sections_of_edge (
+				      f, local_kids[0], children ) );
+			TRY ( _compute_sections_of_edge (
+				      f, local_kids[1], children ) );
+		}
+	}
+	if ( ! refined ) {
+		TRY ( _h5_append_to_idlist ( f, children, te->value.items[0] ) );
 	}
 	return H5_SUCCESS;
 }
 
-/*
-def _compute_children_of_triangle ( D, children ):
-	for D' in T(D):
-		T' = tetrahedron bound to D'
-		if T' has no children on level ≤ L: next
-		(D'0,D'1,D'2,D'3) = _compute_direct_children_of_triangle ( D' )
-		for i in [0,1,2,3]:
-			T'i = tetrahedron bound to D'i
-			if T'i has children on level ≤ L:
-				_compute_children_of_triangle ( D'i, children )
-			else:
-				children.append ( D'i) 
-*/
+h5_err_t
+_compute_direct_children_of_triangle (
+	h5_file_t * const f,
+	h5_id_t face_id,
+	h5_id_t local_eid,
+	h5_id_t	dids[4]
+	) {
+	int off[4][4] = { {1,2,3,7}, {0,2,3,6}, {0,1,3,4}, {0,1,2,5} };
+
+	if ( ( face_id < 0 ) || ( face_id >= 4 ) ) {
+		return  h5_error_internal ( f, __FILE__, __func__, __LINE__ ); 
+	}
+	dids[0] = _h5t_build_edge_id ( face_id, local_eid+off[face_id][0] );
+	dids[1] = _h5t_build_edge_id ( face_id, local_eid+off[face_id][1] );
+	dids[2] = _h5t_build_edge_id ( face_id, local_eid+off[face_id][2] );
+	dids[3] = _h5t_build_edge_id ( face_id, local_eid+off[face_id][3] );
+	return H5_SUCCESS;
+}
+
 h5_err_t
 _compute_children_of_triangle (
 	h5_file_t * const f,
@@ -608,51 +602,89 @@ _compute_children_of_triangle (
 
 	h5t_fdata_t *t = f->t;
 	h5_td_node_t *td;
-	int i, k;
 
-	TRY ( _find_td2 (
+	TRY ( _h5t_find_td2 (
 		      f,
 		      &td,
 		      _h5t_get_face_id ( local_did ),
 		      _h5t_get_elem_id ( local_did ) ) 
 		      );
-	for ( k = 0; k < td->value.num_items; k++ ) {
-		h5_id_t local_eid = _h5t_get_elem_id ( td->value.items[k] );
-		h5_tet_data_t *tet = &t->elems_data.tets[local_eid];
-
-		/* no children? */
-		if ( tet->local_child_eid < 0 )
-			continue;
-		/* no children on current level? */
-		h5_tet_data_t *child = &t->elems_data.tets[tet->local_child_eid];
-		if ( child->level_id > t->cur_level )
-			continue;
-
-		h5_id_t local_dids[4];
-		TRY ( _compute_direct_children_of_triangle (
-			f,
-			td->value.items[k],	/* parent triangle */
-			local_dids ) );		/* result */
-		for ( i = 0; i < 4; i++ ) {
-			local_eid = _h5t_get_elem_id ( local_dids[i] );
-			tet = &t->elems_data.tets[local_eid];
-			/* no children? */
-			h5_id_t l_chld_eid = tet->local_child_eid;
-			if ( ( l_chld_eid < 0 ) ||
-			     ( t->elems_data.tets[l_chld_eid].level_id > t->cur_level)) {
-				TRY ( _h5_append_to_idlist (
-					      f, children, local_dids[i] )
-					);
-			} else {
-				TRY ( _compute_children_of_triangle (
-					      f, local_dids[i], children ) );
-			}
+	h5_id_t *tri = td->value.items;
+	h5_id_t *end = td->value.items+td->value.num_items;
+	for ( ; tri < end; tri++ ) {
+		h5_id_t local_eid = _h5t_get_elem_id ( *tri );
+		h5_id_t face_id =  _h5t_get_face_id ( *tri );
+		h5_elem_ldta_t *tet = &t->elems_ldta[local_eid];
+		if ( _h5t_elem_is_on_cur_level ( f, tet ) == H5_OK ) {
+			TRY ( _h5_append_to_idlist (
+				      f, children, *tri )
+				);
+		} else {
+			h5_id_t local_dids[4];
+			TRY ( _compute_direct_children_of_triangle (
+				      f,
+				      face_id,
+				      tet->local_child_eid,
+				      local_dids ) );
+			TRY ( _compute_children_of_triangle (
+				      f, local_dids[0], children ) );
+			TRY ( _compute_children_of_triangle (
+				      f, local_dids[1], children ) );
+			TRY ( _compute_children_of_triangle (
+				      f, local_dids[2], children ) );
+			TRY ( _compute_children_of_triangle (
+				      f, local_dids[3], children ) );
 		}
 	}
-
 	return H5_SUCCESS;
 }
 
+static h5_err_t
+_compute_sections_of_triangle (
+	h5_file_t * const f,
+	h5_id_t local_did,
+	h5_idlist_t *children
+	) {
+	h5t_fdata_t *t = f->t;
+	h5_td_node_t *td;
+
+	TRY ( _h5t_find_td2 (
+		      f,
+		      &td,
+		      _h5t_get_face_id ( local_did ),
+		      _h5t_get_elem_id ( local_did ) ) 
+		);
+	h5_id_t *tri = td->value.items;
+	h5_id_t *end = td->value.items+td->value.num_items;
+	int refined = 0;
+	for ( ; tri < end; tri++ ) {
+		h5_id_t local_eid = _h5t_get_elem_id ( *tri );
+		h5_id_t face_id =  _h5t_get_face_id ( *tri );
+		h5_elem_ldta_t *tet = &t->elems_ldta[local_eid];
+		if ( ! _h5t_elem_is_on_cur_level ( f, tet ) == H5_OK ) {
+			refined = 1;
+			h5_id_t local_dids[4];
+			TRY ( _compute_direct_children_of_triangle (
+				      f,
+				      face_id,
+				      tet->local_child_eid,
+				      local_dids ) );
+			TRY ( _compute_sections_of_triangle (
+				      f, local_dids[0], children ) );
+			TRY ( _compute_sections_of_triangle (
+				      f, local_dids[1], children ) );
+			TRY ( _compute_sections_of_triangle (
+				      f, local_dids[2], children ) );
+			TRY ( _compute_sections_of_triangle (
+				      f, local_dids[3], children ) );
+
+		}
+	}
+	if ( ! refined ) {
+		TRY ( _h5_append_to_idlist ( f, children, td->value.items[0] ) );
+	}
+	return H5_SUCCESS;
+}
 /*
   map edge ID to unique ID
   if unique ID not in list: add
@@ -661,28 +693,16 @@ static h5_err_t
 _add_edge (
 	h5_file_t * const f,
 	h5_idlist_t *list,
-	h5_2id_t edge
+	h5_id_t face_id,
+	h5_id_t local_eid
 	) {
 	h5_te_node_t *te;
-	TRY ( _find_te ( f, &te, edge ) );
-	/* search/add unique ID */
-	_h5_search_idlist ( f, list, te->value.items[0] );
+	TRY ( _h5t_find_te2 ( f, &te, face_id, local_eid ) );
+	TRY ( _h5_search_idlist ( f, list, te->value.items[0] ) );
 
 	return H5_SUCCESS;
 }
 
-h5_id_t *
-_h5t_get_edge_of_tet (
-	const h5_tet_data_t *tet,
-	const h5_id_t face_id,
-	h5_2id_t edge
-	) {
-	int map[6][2] = { { 0,1 }, {1,2}, {0,2}, {0,3}, {1,3}, {2,3} };
-
- 	edge[0] = tet->local_vids[map[face_id][0]];
-	edge[1] = tet->local_vids[map[face_id][1]];
-	return edge;
-}
 
 h5_err_t
 h5t_get_edges_upadjacent_to_vertex (
@@ -696,22 +716,19 @@ h5t_get_edges_upadjacent_to_vertex (
 	h5_idlist_t *tv = &t->vertices_data[local_vid].tv;
 	h5_size_t i;
 
-	for ( i = 0; i < tv->num_items; i++ ) {
-		h5_id_t local_eid = _h5t_get_elem_id ( tv->items[i] );
-		h5_id_t vertex_id = _h5t_get_face_id ( tv->items[i] );
-		h5_tet_data_t *tet = &t->elems_data.tets[local_eid];
+	h5_id_t *vid = tv->items;
+	for ( i = 0; i < tv->num_items; i++, vid++ ) {
+		h5_id_t local_eid = _h5t_get_elem_id ( *vid );
+		h5_id_t face_id = _h5t_get_face_id ( *vid );
+		h5_elem_ldta_t *tet = &t->elems_ldta[local_eid];
 
-		if ( _h5t_elem_is_on_cur_level ( f, (h5_element_data_t*)tet ) == H5_NOK ) {
+		if ( _h5t_elem_is_on_cur_level ( f, tet ) == H5_NOK ) {
 			continue;
 		}
 		int map[4][3] = { { 0, 2, 3 }, { 0, 1, 4 }, { 2, 1, 5 }, { 3, 4, 5} };
-		h5_2id_t edge;
-		TRY ( _add_edge ( f, *list,
-				  _h5t_get_edge_of_tet(tet, map[vertex_id][0], edge) ) );
-		TRY ( _add_edge ( f, *list,
-				  _h5t_get_edge_of_tet(tet, map[vertex_id][1], edge) ) );
-		TRY ( _add_edge ( f, *list,
-				  _h5t_get_edge_of_tet(tet, map[vertex_id][2], edge) ) );
+		TRY ( _add_edge ( f, *list, map[face_id][0], local_eid ) );
+		TRY ( _add_edge ( f, *list, map[face_id][1], local_eid ) );
+		TRY ( _add_edge ( f, *list, map[face_id][2], local_eid ) );
 	}
 	return H5_SUCCESS;
 }
@@ -720,10 +737,11 @@ static h5_err_t
 _add_triangle (
 	h5_file_t * const f,
 	h5_idlist_t *list,
-	h5_3id_t tri
+	h5_id_t face_id,
+	h5_id_t local_eid
 	) {
 	h5_td_node_t *td;
-	TRY ( _find_td ( f, &td, tri ) );
+	TRY ( _h5t_find_td2 ( f, &td, face_id, local_eid ) );
 	TRY ( _h5_search_idlist ( f, list, td->value.items[0] ) );
 
 	return H5_SUCCESS;
@@ -740,26 +758,19 @@ h5t_get_triangles_upadjacent_to_vertex (
 	h5t_fdata_t *t = f->t;
 	h5_idlist_t *tv = &t->vertices_data[local_vid].tv;
 	h5_size_t i;
+	h5_id_t *vid = tv->items;
+	for ( i = 0; i < tv->num_items; i++, vid++ ) {
+		h5_id_t local_eid = _h5t_get_elem_id ( *vid );
+		h5_id_t face_id = _h5t_get_face_id ( *vid );
+		h5_elem_ldta_t *tet = &t->elems_ldta[local_eid];
 
-	for ( i = 0; i < tv->num_items; i++ ) {
-		h5_id_t local_eid = _h5t_get_elem_id ( tv->items[i] );
-		h5_id_t vertex_id = _h5t_get_face_id ( tv->items[i] );
-		h5_tet_data_t *tet = &t->elems_data.tets[local_eid];
-
-		if ( _h5t_elem_is_on_cur_level ( f, (h5_element_data_t*)tet ) == H5_NOK ) {
+		if ( _h5t_elem_is_on_cur_level ( f, tet ) == H5_NOK ) {
 			continue;
 		}
 		int map[4][3] = { { 1, 2, 3 }, { 0, 2, 3 }, { 0, 1, 3 }, { 0, 1, 2} };
-		h5_3id_t tri;
-		TRY ( _add_triangle (
-			      f, *list,
-			      _h5t_get_triangle_of_tet(tet, map[vertex_id][0], tri) ) );
-		TRY ( _add_triangle (
-			      f, *list,
-			      _h5t_get_triangle_of_tet(tet, map[vertex_id][1], tri) ) );
-		TRY ( _add_triangle (
-			      f, *list,
-			      _h5t_get_triangle_of_tet(tet, map[vertex_id][2], tri) ) );
+		TRY ( _add_triangle ( f, *list, map[face_id][0], local_eid ) );
+		TRY ( _add_triangle ( f, *list, map[face_id][1], local_eid ) );
+		TRY ( _add_triangle ( f, *list, map[face_id][2], local_eid ) );
 	}
 	return H5_SUCCESS;
 }
@@ -775,12 +786,12 @@ h5t_get_tets_upadjacent_to_vertex (
 	h5t_fdata_t *t = f->t;
 	h5_idlist_t *tv = &t->vertices_data[local_vid].tv;
 	h5_size_t i;
+	h5_id_t *vid = tv->items;
+	for ( i = 0; i < tv->num_items; i++, vid++ ) {
+		h5_id_t local_eid = _h5t_get_elem_id ( *vid );
+		h5_elem_ldta_t *tet = &t->elems_ldta[local_eid];
 
-	for ( i = 0; i < tv->num_items; i++ ) {
-		h5_id_t local_eid = _h5t_get_elem_id ( tv->items[i] );
-		h5_tet_data_t *tet = &t->elems_data.tets[local_eid];
-
-		if ( _h5t_elem_is_on_cur_level ( f, (h5_element_data_t*)tet ) == H5_NOK ) {
+		if ( _h5t_elem_is_on_cur_level ( f, tet ) == H5_NOK ) {
 			continue;
 		}
 		TRY ( _h5_search_idlist ( f, *list, local_eid ) );
@@ -788,21 +799,235 @@ h5t_get_tets_upadjacent_to_vertex (
 	return H5_SUCCESS;
 }
 
+h5_err_t
+h5t_get_triangles_upadjacent_to_edge (
+	h5_file_t * const f,
+	const h5_id_t local_kid,
+	h5_idlist_t **list
+	) {
+	h5_idlist_t *children;
+	TRY ( _h5_alloc_idlist ( f, &children, 8 ) );
+	TRY ( _compute_children_of_edge ( f, local_kid, children ) );
+	TRY ( _h5_alloc_idlist ( f, list, 8 ) );
+	h5_id_t *edge = children->items;
+	h5_id_t *end = children->items+children->num_items;
+	int map[6][2] = { {2,3}, {0,3}, {1,3}, {1,2}, {0,2}, {0,1} };
+	for ( ; edge < end; edge++ ) {
+		h5_id_t local_eid = _h5t_get_elem_id ( *edge );
+		h5_id_t face_id = _h5t_get_face_id ( *edge );
+		TRY ( _add_triangle ( f, *list, map[face_id][0], local_eid ) );
+		TRY ( _add_triangle ( f, *list, map[face_id][1], local_eid ) );
+	}
+	TRY ( _h5_free_idlist( f, &children ) );
+
+	return H5_SUCCESS;
+}
+
 h5_err_t
 h5t_get_tets_upadjacent_to_edge (
 	h5_file_t * const f,
 	const h5_id_t local_kid,
 	h5_idlist_t **list
 	) {
-	h5_idlist_t children;
-	memset ( &children, 0, sizeof(children) );
+	h5_idlist_t *children;
+	TRY ( _h5_alloc_idlist ( f, &children, 8 ) );
+	TRY( _compute_children_of_edge ( f, local_kid, children ) );
 	TRY ( _h5_alloc_idlist ( f, list, 8 ) );
-	TRY( _compute_children_of_edge ( f, local_kid, &children ) );
 	int i;
-	for ( i = 0; i < children.num_items; i++ ) {
-		h5_id_t local_eid = _h5t_get_elem_id ( children.items[i] );
+	h5_id_t *kid = children->items;
+	for ( i = 0; i < children->num_items; i++, kid++ ) {
+		h5_id_t local_eid = _h5t_get_elem_id ( *kid );
 		TRY ( _h5_search_idlist ( f, *list, local_eid ) );
 	}
+	TRY ( _h5_free_idlist( f, &children ) );
+	return H5_SUCCESS;
+}
+
+h5_err_t
+h5t_get_tets_upadjacent_to_triangle (
+	h5_file_t * const f,
+	const h5_id_t local_did,
+	h5_idlist_t **list
+	) {
+	h5_idlist_t *children;
+	TRY ( _h5_alloc_idlist ( f, &children, 8 ) );
+	TRY( _compute_children_of_triangle ( f, local_did, children ) );
+	TRY ( _h5_alloc_idlist ( f, list, 8 ) );
+	int i;
+	h5_id_t *did = children->items;
+	for ( i = 0; i < children->num_items; i++ , did++) {
+		h5_id_t local_eid = _h5t_get_elem_id ( *did );
+		TRY ( _h5_search_idlist ( f, *list, local_eid ) );
+	}
+	TRY ( _h5_free_idlist( f, &children ) );
+	return H5_SUCCESS;
+}
+
+
+h5_err_t
+h5t_get_vertices_downadjacent_to_edge (
+	h5_file_t * const f,
+	const h5_id_t local_kid,
+	h5_idlist_t **list
+	) {
+	h5_idlist_t *children;
+	TRY ( _h5_alloc_idlist ( f, &children, 8 ) );
+	TRY( _compute_sections_of_edge ( f, local_kid, children ) );
+	TRY ( _h5_alloc_idlist ( f, list, 8 ) );
+	int i;
+	h5_id_t *kid = children->items;
+	for ( i = 0; i < children->num_items; i++, kid++ ) {
+		h5_2id_t local_vids;
+		TRY ( h5t_get_local_vids_of_entity ( f, *kid, local_vids ) );
+		TRY ( _h5_search_idlist ( f, *list, local_vids[0] ) );
+		TRY ( _h5_search_idlist ( f, *list, local_vids[1] ) );
+	}
+	TRY ( _h5_free_idlist( f, &children ) );
+	return H5_SUCCESS;
+}
+
+/*
+  Compute downward adjacent vertices of all edges of triangle.
+ */
+h5_err_t
+h5t_get_vertices_downadjacent_to_triangle (
+	h5_file_t * const f,
+	const h5_id_t local_did,
+	h5_idlist_t **list
+	) {
+	h5_idlist_t *children;
+	TRY ( _h5_alloc_idlist ( f, &children, 8 ) );
+
+	int map[4][3] = { {1,4,5}, {2,3,5}, {0,3,4}, {0,1,2} };
+	h5_id_t face_id = _h5t_get_face_id ( local_did );
+	h5_id_t local_eid = _h5t_get_elem_id ( local_did );
+
+	h5_id_t i;
+	for ( i = 0; i < 3; i++ ) {
+		TRY( _compute_sections_of_edge (
+			     f,
+			     _h5t_build_edge_id ( map[face_id][i], local_eid ),
+			     children ) );
+	}
+	TRY ( _h5_alloc_idlist ( f, list, 8 ) );
+	h5_id_t *kid = children->items;
+	for ( i = 0; i < children->num_items; i++, kid++ ) {
+		h5_2id_t local_vids;
+		TRY ( h5t_get_local_vids_of_entity ( f, *kid, local_vids ) );
+		TRY ( _h5_search_idlist ( f, *list, local_vids[0] ) );
+		TRY ( _h5_search_idlist ( f, *list, local_vids[1] ) );
+	}
+	TRY ( _h5_free_idlist( f, &children ) );
+	return H5_SUCCESS;
+}
+
+/*
+  Compute downward adjacent vertices of all edges of tetrahedron.
+ */
+h5_err_t
+h5t_get_vertices_downadjacent_to_tet (
+	h5_file_t * const f,
+	const h5_id_t local_eid,
+	h5_idlist_t **list
+	) {
+	h5_idlist_t *children;
+	TRY ( _h5_alloc_idlist ( f, &children, 8 ) );
+
+	h5_id_t i;
+	for ( i = 0; i < 6; i++ ) {
+		TRY( _compute_sections_of_edge (
+			     f,
+			     _h5t_build_edge_id ( i, local_eid ),
+			     children ) );
+	}
+	TRY ( _h5_alloc_idlist ( f, list, 8 ) );
+	h5_id_t *kid = children->items;
+	for ( i = 0; i < children->num_items; i++, kid++ ) {
+		h5_2id_t local_vids;
+		TRY ( h5t_get_local_vids_of_entity ( f, *kid, local_vids ) );
+		TRY ( _h5_search_idlist ( f, *list, local_vids[0] ) );
+		TRY ( _h5_search_idlist ( f, *list, local_vids[1] ) );
+	}
+	TRY ( _h5_free_idlist( f, &children ) );
+	return H5_SUCCESS;
+}
+
+h5_err_t
+h5t_get_edges_downadjacent_to_triangle (
+	h5_file_t * const f,
+	const h5_id_t local_did,
+	h5_idlist_t **list
+	) {
+	h5_idlist_t *children;
+	TRY ( _h5_alloc_idlist ( f, &children, 8 ) );
+
+	int map[4][3] = { {1,4,5}, {2,3,5}, {0,3,4}, {0,1,2} };
+	h5_id_t face_id = _h5t_get_face_id ( local_did );
+	h5_id_t local_eid = _h5t_get_elem_id ( local_did );
+
+	h5_id_t i;
+	for ( i = 0; i < 3; i++ ) {
+		TRY( _compute_sections_of_edge (
+			     f,
+			     _h5t_build_edge_id ( map[face_id][i], local_eid ),
+			     children ) );
+	}
+	TRY ( _h5_alloc_idlist ( f, list, 8 ) );
+	h5_id_t *kid = children->items;
+	for ( i = 0; i < children->num_items; i++, kid++ ) {
+		TRY ( _h5_search_idlist ( f, *list, *kid ) );
+	}
+	TRY ( _h5_free_idlist( f, &children ) );
+	return H5_SUCCESS;
+}
+
+h5_err_t
+h5t_get_edges_downadjacent_to_tet (
+	h5_file_t * const f,
+	const h5_id_t local_eid,
+	h5_idlist_t **list
+	) {
+	h5_idlist_t *children;
+	TRY ( _h5_alloc_idlist ( f, &children, 8 ) );
+
+	h5_id_t i;
+	for ( i = 0; i < 6; i++ ) {
+		TRY( _compute_sections_of_edge (
+			     f,
+			     _h5t_build_edge_id ( i, local_eid ),
+			     children ) );
+	}
+	TRY ( _h5_alloc_idlist ( f, list, 8 ) );
+	h5_id_t *kid = children->items;
+	for ( i = 0; i < children->num_items; i++, kid++ ) {
+		TRY ( _h5_search_idlist ( f, *list, *kid ) );
+	}
+	TRY ( _h5_free_idlist( f, &children ) );
+	return H5_SUCCESS;
+}
+
+h5_err_t
+h5t_get_triangles_downadjacent_to_tet (
+	h5_file_t * const f,
+	const h5_id_t local_eid,
+	h5_idlist_t **list
+	) {
+	h5_idlist_t *children;
+	TRY ( _h5_alloc_idlist ( f, &children, 8 ) );
+
+	h5_id_t i;
+	for ( i = 0; i < 4; i++ ) {
+		TRY( _compute_sections_of_triangle (
+			     f,
+			     _h5t_build_edge_id ( i, local_eid ),
+			     children ) );
+	}
+	TRY ( _h5_alloc_idlist ( f, list, 8 ) );
+	h5_id_t *did = children->items;
+	for ( i = 0; i < children->num_items; i++, did++ ) {
+		TRY ( _h5_search_idlist ( f, *list, *did ) );
+	}
+	TRY ( _h5_free_idlist( f, &children ) );
 	return H5_SUCCESS;
 }
 
diff --git a/src/h5_core/h5t_adjacencies.h b/src/h5_core/h5t_adjacencies.h
index 7274cfd..f551556 100644
--- a/src/h5_core/h5t_adjacencies.h
+++ b/src/h5_core/h5t_adjacencies.h
@@ -22,6 +22,69 @@ h5t_get_tets_upadjacent_to_vertex (
 	h5_idlist_t **list
 	);
 
+h5_err_t
+h5t_get_triangles_upadjacent_to_edge (
+	h5_file_t * const f,
+	const h5_id_t local_kid,
+	h5_idlist_t **list
+	);
+
+h5_err_t
+h5t_get_tets_upadjacent_to_edge (
+	h5_file_t * const f,
+	const h5_id_t local_kid,
+	h5_idlist_t **list
+	);
+
+h5_err_t
+h5t_get_tets_upadjacent_to_triangle (
+	h5_file_t * const f,
+	const h5_id_t local_did,
+	h5_idlist_t **list
+	);
+
+h5_err_t
+h5t_get_vertices_downadjacent_to_edge (
+	h5_file_t * const f,
+	const h5_id_t local_kid,
+	h5_idlist_t **list
+	);
+
+h5_err_t
+h5t_get_vertices_downadjacent_to_triangle (
+	h5_file_t * const f,
+	const h5_id_t local_did,
+	h5_idlist_t **list
+	);
+
+h5_err_t
+h5t_get_vertices_downadjacent_to_tet (
+	h5_file_t * const f,
+	const h5_id_t local_tid,
+	h5_idlist_t **list
+	);
+
+h5_err_t
+h5t_get_edges_downadjacent_to_triangle (
+	h5_file_t * const f,
+	const h5_id_t local_did,
+	h5_idlist_t **list
+	);
+
+h5_err_t
+h5t_get_edges_downadjacent_to_tet (
+	h5_file_t * const f,
+	const h5_id_t local_tid,
+	h5_idlist_t **list
+	);
+
+h5_err_t
+h5t_get_triangles_downadjacent_to_tet (
+	h5_file_t * const f,
+	const h5_id_t local_tid,
+	h5_idlist_t **list
+	);
+
 h5_err_t
 h5t_release_list_of_adjacencies (
 	h5_file_t * const f,
diff --git a/src/h5_core/h5t_adjacencies_private.h b/src/h5_core/h5t_adjacencies_private.h
index 03f2531..d37d50b 100644
--- a/src/h5_core/h5t_adjacencies_private.h
+++ b/src/h5_core/h5t_adjacencies_private.h
@@ -14,4 +14,18 @@ _h5t_find_te2 (
 	h5_id_t local_eid
 	);
 
+h5_err_t
+_h5t_find_td (
+	h5_file_t * const f,
+	h5_td_node_t **rnode,
+	h5_3id_t tri
+	);
+
+h5_err_t
+_h5t_find_td2 (
+	h5_file_t * const f,
+	h5_td_node_t **rnode,
+	h5_id_t face_id,
+	h5_id_t local_eid
+	);
 #endif
diff --git a/src/h5_core/h5t_boundaries.c b/src/h5_core/h5t_boundaries.c
index 171b724..276be35 100644
--- a/src/h5_core/h5t_boundaries.c
+++ b/src/h5_core/h5t_boundaries.c
@@ -237,27 +237,9 @@ h5t_store_boundaryface (
 	h5_file_t * const f,
 	h5_id_t * const global_vids
 	) {
-	struct h5t_fdata *t = f->t;
 
-	if ( t->vertices == NULL ) {
-		TRY ( _h5t_read_mesh ( f ) );
-	}
-
-	switch ( t->mesh_type ) {
-	case H5_OID_TETRAHEDRON: {
-		h5_id_t local_vids[3];
-		h5_err_t h5err = h5t_map_global_vids2local (
-			f, global_vids, 3, local_vids );
-		if ( h5err < 0 ) return h5err;
-		h5_id_t local_tid = h5t_get_local_triangle_id ( f, local_vids );
-		if ( local_tid < 0 )
-			return _h5t_error_local_triangle_id_nexist( f, local_vids );
-		return h5t_store_boundaryface_local_id ( f, local_tid );
-	}
-	default:
-		return h5_error_not_implemented (
-			f, __FILE__, __func__, __LINE__ );
-	}
+	return h5_error_not_implemented (
+		f, __FILE__, __func__, __LINE__ );
 }
 
 h5_id_t
diff --git a/src/h5_core/h5t_consts.c b/src/h5_core/h5t_consts.c
index 26347f2..b4d704d 100644
--- a/src/h5_core/h5t_consts.c
+++ b/src/h5_core/h5t_consts.c
@@ -1,4 +1,6 @@
 #include "h5_types.h"
+#include "h5_types_private.h"
+#include "h5t_types_private.h"
 
 const char * _h5t_oid_names[] = {
 	"N.N.",
@@ -16,6 +18,14 @@ const char * _h5t_meshes_grpnames[] = {
 	"TetMeshes"
 };
 
+const size_t _h5t_sizeof_elem[] = {
+	0,
+	0,
+	0,
+	sizeof(h5_triangle_t),
+	sizeof(h5_tetrahedron_t)
+};
+
 const char *
 _h5t_map_oid2str (
 	h5_oid_t oid
diff --git a/src/h5_core/h5t_consts_private.h b/src/h5_core/h5t_consts_private.h
index 47bc73d..394adf0 100644
--- a/src/h5_core/h5t_consts_private.h
+++ b/src/h5_core/h5t_consts_private.h
@@ -3,6 +3,7 @@
 
 extern char * _h5t_oid_names[];
 extern char * _h5t_meshes_grpnames[];
+extern size_t _h5t_sizeof_elem[];
 
 const char *
 _h5t_map_oid2str (
diff --git a/src/h5_core/h5t_errorhandling.c b/src/h5_core/h5t_errorhandling.c
index d8fb814..f6a8827 100644
--- a/src/h5_core/h5t_errorhandling.c
+++ b/src/h5_core/h5t_errorhandling.c
@@ -8,27 +8,31 @@
 
 #include "h5_core.h"
 #include "h5_core_private.h"
-	
+
+
 h5_err_t
-_h5t_error_illegal_object_type (
+_h5t_error_local_elem_nexist (
 	h5_file_t * const f,
-	h5_oid_t oid ) {
-	struct h5t_fdata *t = f->t;
-	switch ( t->mesh_type ) {
+	h5_id_t local_vids[]
+	) {
+	switch ( f->t->mesh_type ) {
 	case H5_OID_TETRAHEDRON:
-		return h5_error_internal( f, __FILE__, __func__, __LINE__ );
+		return h5_error (
+			f,
+			H5_ERR_NOENTRY,
+			"Tetrahedron with local vertex IDs "
+			"(%lld,%lld,%lld,%lld) doesn't exist!",
+			local_vids[0], local_vids[1],
+			local_vids[2], local_vids[3] );
 	case H5_OID_TRIANGLE:
-		switch ( oid ) {
-		case H5_OID_TETRAHEDRON:
-			return h5_error (
-				f,
-				H5_ERR_INVAL,
-				"Illegal topological entity tetrahedron"
-				" in triangle mesh." );
-		default:
-			return h5_error_internal( f, __FILE__, __func__, __LINE__ );
-		}
+		return h5_error (
+			f,
+			H5_ERR_NOENTRY,
+			"Triangle with local vertex IDs "
+			"(%lld,%lld,%lld) doesn't exist!",
+			local_vids[0], local_vids[1], local_vids[2] );
 	default:
 		return h5_error_internal( f, __FILE__, __func__, __LINE__ );
 	}
 }
+	
diff --git a/src/h5_core/h5t_errorhandling_private.h b/src/h5_core/h5t_errorhandling_private.h
index cb080fb..b1a2089 100644
--- a/src/h5_core/h5t_errorhandling_private.h
+++ b/src/h5_core/h5t_errorhandling_private.h
@@ -2,9 +2,10 @@
 #define __H5T_ERRORHANDLING_PRIVATE_H
 
 h5_err_t
-_h5t_error_illegal_object_type (
+_h5t_error_local_elem_nexist (
 	h5_file_t * const f,
-	h5_oid_t oid );
+	h5_id_t local_vids[]
+	);
 
 #define _h5t_error_undef_mesh( f )		\
 	h5_error(				\
@@ -12,11 +13,18 @@ _h5t_error_illegal_object_type (
 		H5_ERR_INVAL,			\
 		"Mesh not yet defined." );
 
-#define _h5t_error_undef_level( f )		\
+#define _h5t_error_undef_level( f )	\
 	h5_error(				\
 		f,				\
 		H5_ERR_INVAL,			\
-		"Level not yet defined." );
+		"Level not defined." );
+
+
+#define _h5t_error_nexist_level( f, level_id )	\
+	h5_error(				\
+		f,				\
+		H5_ERR_INVAL,			\
+		"Level %lld doesn't exist.", level_id );
 
 #define _h5t_error_global_id_nexist( f, name, id )		\
 	h5_error(						\
@@ -26,34 +34,6 @@ _h5t_error_illegal_object_type (
 		name, id );
 
 
-#define _h5t_error_global_tet_id_nexist( f, vids )			\
-	h5_error(							\
-		f,							\
-		H5_ERR_NOENTRY,						\
-		"Tetrahedron with global vertex ids (%lld,%lld,%lld,%lld) doesn't exist!", \
-		vids[0], vids[1], vids[2], vids[3] );
-
-#define _h5t_error_global_tri_id_nexist( f, vids )			\
-	h5_error(							\
-		f,							\
-		H5_ERR_NOENTRY,						\
-		"Triangle with global vertex ids (%lld,%lld,%lld) doesn't exist!", \
-		vids[0], vids[1], vids[2] );
-
-#define _h5t_error_local_tet_id_nexist( f, vids )			\
-	h5_error(							\
-		f,							\
-		H5_ERR_NOENTRY,						\
-		"Tetrahedron with local vertex ids (%lld,%lld,%lld,%lld) doesn't exist!", \
-		vids[0], vids[1], vids[2], vids[3] );
-
-#define _h5t_error_local_triangle_id_nexist( f, vids )			\
-	h5_error(							\
-		f,							\
-		H5_ERR_NOENTRY,						\
-		"Triangle with local vertex ids (%lld,%lld,%lld) doesn't exist!", \
-		vids[0], vids[1], vids[2] );
-
 #define _h5t_error_global_triangle_id_nexist( f, vids )			\
 	h5_error(							\
 		f,							\
@@ -61,6 +41,14 @@ _h5t_error_illegal_object_type (
 		"Triangle with global vertex ids (%lld,%lld,%lld) doesn't exist!", \
 		vids[0], vids[1], vids[2] );
 
+#define _h5t_error_local_triangle_nexist( f, local_vids )			\
+	h5_error(							\
+		f,							\
+		H5_ERR_NOENTRY,						\
+		"Triangle with global vertex ids (%lld,%lld,%lld) doesn't exist!", \
+		local_vids[0], local_vids[1], local_vids[2] );
+
+
 #define _h5t_error_store_boundaryface_local_id( f, local_fid )	     \
 	h5_error(						     \
 		f,						     \
diff --git a/src/h5_core/h5t_inquiry.c b/src/h5_core/h5t_inquiry.c
index 39e7ce2..c3d691d 100644
--- a/src/h5_core/h5t_inquiry.c
+++ b/src/h5_core/h5t_inquiry.c
@@ -16,7 +16,7 @@ h5t_get_num_meshes (
 	) {
 	struct h5t_fdata *t = f->t;
 
-	if ( t->num_meshes != -1 ) {
+	if ( t->num_meshes >= 0 ) {
 		return t->num_meshes;
 	}
 	if ( t->topo_gid < 0 ) {
@@ -36,25 +36,12 @@ h5_size_t
 h5t_get_num_levels (
 	h5_file_t * f
 	) {
-	struct h5t_fdata *t = f->t;
-	hid_t dataset_id;
-	hid_t diskspace_id;
-	hssize_t size;
+	h5t_fdata_t *t = f->t;
 
-	if ( t->num_levels >= 0 ) return t->num_levels;
 	if ( t->cur_mesh < 0 ) {
 		return _h5t_error_undef_mesh ( f );
 	}
-	if ( t->mesh_gid < 0 ) {
-		TRY( _h5t_open_mesh_group ( f ) );
-	}
-	TRY ( dataset_id = _h5_open_dataset ( f, t->mesh_gid, "NumVertices" ) );
-	TRY ( diskspace_id = _h5_get_dataset_space ( f, dataset_id ) );
-	TRY ( size = _h5_get_npoints_of_space ( f, diskspace_id ) );
-	TRY ( _h5_close_dataspace( f, diskspace_id ) );
-
-	t->num_levels = size;
-	return size;
+	return t->num_levels;
 }
 
 
@@ -107,27 +94,18 @@ h5t_get_num_levels (
 h5_size_t
 h5t_get_num_elems (
 	h5_file_t * f,
-	hid_t cnode_id,
-	hid_t level_id
+	h5_id_t cnode_id,
+	h5_id_t level_id
 	) {
-	struct h5t_fdata *t = f->t;
+	h5t_fdata_t *t = f->t;
 
-	if ( cnode_id < 0 ) {
-		cnode_id = f->nprocs;
-	}
-	if ( level_id < 0 ) {
-		level_id = f->t->num_levels-1;
-	}
 	if ( t->cur_mesh < 0 ) {
 		return _h5t_error_undef_mesh ( f );
 	}
-	if ( t->cur_level < 0 ) {
-		return _h5t_error_undef_level( f );
+	if ( level_id < 0 || level_id >= t->num_levels ) {
+		return HANDLE_H5_OUT_OF_RANGE_ERR ( f, "Level", level_id );
 	}
-	if ( t->num_elems_on_level == NULL ) {
-		TRY( _h5t_read_num_elems ( f ) );
-	}
-	return t->num_elems_on_level[t->cur_level];
+	return t->num_elems_on_level[level_id];
 }
 
 /*!
@@ -140,22 +118,15 @@ h5t_get_num_elems (
 h5_size_t
 h5t_get_num_elems_total (
 	h5_file_t * f,
-	hid_t cnode_id,
-	hid_t level_id
+	h5_id_t cnode_id,
+	h5_id_t level_id
 	) {
-	struct h5t_fdata *t = f->t;
-
-	if ( cnode_id < 0 ) {
-		cnode_id = f->nprocs;
-	}
-	if ( level_id < 0 ) {
-		level_id = f->t->num_levels-1;
-	}
+	h5t_fdata_t *t = f->t;
 	if ( t->cur_mesh < 0 ) {
 		return _h5t_error_undef_mesh ( f );
 	}
-	if ( t->num_elems == NULL ) {
-		TRY( _h5t_read_num_elems ( f ) );
+	if ( level_id < 0 || level_id >= t->num_levels ) {
+		return HANDLE_H5_OUT_OF_RANGE_ERR ( f, "Level", level_id );
 	}
 	return t->num_elems[level_id];
 }
@@ -172,25 +143,16 @@ h5t_get_num_elems_total (
 h5_size_t
 h5t_get_num_vertices (
 	h5_file_t * f,
-	hid_t cnode_id,
-	hid_t level_id
+	h5_id_t cnode_id,
+	h5_id_t level_id
 	) {
-	struct h5t_fdata *t = f->t;
+	h5t_fdata_t *t = f->t;
 
-	if ( cnode_id < 0 ) {
-		cnode_id = f->nprocs;
-	}
-	if ( level_id < 0 ) {
-		level_id = f->t->num_levels-1;
-	}
 	if ( t->cur_mesh < 0 ) {
 		return _h5t_error_undef_mesh ( f );
 	}
-	if ( t->cur_level < 0 ) {
-		return _h5t_error_undef_level( f );
-	}
-	if ( t->num_vertices == NULL ) {
-		TRY( _h5t_read_num_vertices ( f ) );
+	if ( level_id < 0 || level_id >= t->num_levels ) {
+		return HANDLE_H5_OUT_OF_RANGE_ERR ( f, "Level", level_id );
 	}
 	return t->num_vertices[level_id];
 }
@@ -199,6 +161,5 @@ h5_id_t
 h5t_get_level (
 	h5_file_t * f
 	) {
-	struct h5t_fdata *t = f->t;
-	return t->cur_level;
+	return f->t->cur_level;
 }
diff --git a/src/h5_core/h5t_inquiry.h b/src/h5_core/h5t_inquiry.h
index ccd601e..87df0e5 100644
--- a/src/h5_core/h5t_inquiry.h
+++ b/src/h5_core/h5t_inquiry.h
@@ -15,22 +15,22 @@ h5t_get_num_levels (
 h5_size_t
 h5t_get_num_elems (
 	h5_file_t * f,
-	hid_t cnode_id,
-	hid_t level_id
+	h5_id_t cnode_id,
+	h5_id_t level_id
 	);
 
 h5_size_t
 h5t_get_num_elems_total (
 	h5_file_t * f,
-	hid_t cnode_id,
-	hid_t level_id
+	h5_id_t cnode_id,
+	h5_id_t level_id
 	);
 
 h5_size_t
 h5t_get_num_vertices (
 	h5_file_t * f,
-	hid_t cnode_id,
-	hid_t level_id
+	h5_id_t cnode_id,
+	h5_id_t level_id
 	);
 
 h5_id_t
diff --git a/src/h5_core/h5t_map.c b/src/h5_core/h5t_map.c
index 0bd1e59..3b2d775 100644
--- a/src/h5_core/h5t_map.c
+++ b/src/h5_core/h5t_map.c
@@ -75,20 +75,19 @@ _h5t_sort_vertices (
 	return H5_SUCCESS;
 }
 
+
 /*!
-  Search vertex in the sorted array of vertices. The vertex is given by its 
-  coordinates.
+  Return local vertex id of a vertex given by its coordinates.
 
-  \return	index of vertex in the sorted array or the negative value 
-		of the index where it should be inserted.
-*/
-static h5_id_t
-_search_vertex (
+  \return	local vertex id if found
+  \return	else negativ value
+ */
+h5_id_t
+_h5t_get_local_vid (
 	h5_file_t * const f,
-	h5_float64_t P0[3]
+	h5_float64_t P[3]
 	) {
-	struct h5t_fdata *t = f->t;
-
+	h5t_fdata_t *t = f->t;
 	register h5_id_t low = 0;
 	register h5_id_t high = t->sorted_lvertices.num_items - 1;
 	while (low <= high) {
@@ -96,101 +95,26 @@ _search_vertex (
 
 		h5_id_t local_vid = t->sorted_lvertices.items[mid];
 		h5_float64_t *P1 = t->vertices[local_vid].P;
-	        int diff = _cmp_vertices ( P0, P1 );
+	        int diff = _cmp_vertices ( P, P1 );
            	if ( diff < 0 )
                		high = mid - 1;
            	else if ( diff > 0 )
                		low = mid + 1;
            	else
-               		return mid; // found
+               		return t->sorted_lvertices.items[mid]; // found
        	}
        	return -(low+1);  // not found
 }
 
-/*!
-  Return local vertex id of a vertex given by its coordinates.
-
-  \return	local vertex id if found
-  \return	negativ value
- */
-h5_id_t
-_h5t_get_local_vid (
-	h5_file_t * const f,
-	h5_float64_t P[3]
-	) {
-	struct h5t_fdata *t = f->t;
-
-	h5_id_t idx;
-	idx = _search_vertex ( f, P );
-	if ( idx < 0 ) return idx;
-	return t->sorted_lvertices.items[idx];
-}
-
-/*!
-  Returns the local vertex id of the i-th vertex of an element. For triangles
-  i is in [0,1,2], for tetraheda i is in [0,1,2,3].
-*/
-static h5_id_t 
-_get_local_vid_of_elem (
-	h5_file_t * f,
-	int  ith_vertex,
-	h5_id_t local_eid
-	) {
-	struct h5t_fdata *t = f->t;
-
-	h5_id_t local_vid = -1;
-	h5_id_t global_vid = -1;
-
-	switch ( t->mesh_type ) {
-	case H5_OID_TETRAHEDRON: {
-		local_vid = t->elems_data.tets[local_eid].local_vids[ith_vertex];
-		if ( local_vid == -1 ) {
-			global_vid =
-				t->elems.tets[local_eid].global_vids[ith_vertex];
-			local_vid = _h5_search_idmap (
-				&t->map_vertex_g2l, global_vid );
-			t->elems_data.tets[local_eid].local_vids[ith_vertex] =
-				local_vid;
-		}
-		break;
-	}
-	case H5_OID_TRIANGLE: {
-		local_vid = t->elems_data.tris[local_eid].local_vids[ith_vertex];
-		if ( local_vid == -1 ) {
-			global_vid =
-				t->elems.tris[local_eid].global_vids[ith_vertex];
-			local_vid = _h5_search_idmap (
-				&t->map_vertex_g2l, global_vid );
-			t->elems_data.tris[local_eid].local_vids[ith_vertex] =
-				local_vid;
-		}
-		break;
-	}
-	default:
-		return  h5_error_internal ( f, __FILE__, __func__, __LINE__ ); 
-	}
-	return local_vid;
-}
-
 /*!
   Return the coordinates of the i-th vertex of the element given by its local 
   element id. For triangles \c i is in \c [0,1,2], for tetraheda \c i is in
   \c [0,1,2,3].
-*/
-static h5_float64_t*
-_get_vertex_of_elem (
-	h5_file_t * f,
-	int  ith_vertex,
-	h5_id_t local_eid
-	) {
-	struct h5t_fdata *t = f->t;
 
-	h5_id_t local_vid = _get_local_vid_of_elem (
-		f, ith_vertex, local_eid );
-	if ( local_vid == -1 ) 
-		return NULL;
-	return t->vertices[local_vid].P;
-}
+  t->elems_ldta[local_eid].local_vids[i]
+*/
+#define _get_vertex_of_elem( f, i, local_eid ) \
+	(f->t->vertices[ f->t->elems_ldta[local_eid].local_vids[i] ].P)
 
 
 
@@ -385,7 +309,7 @@ _search_elem (
 	h5_file_t *f,
 	h5_id_t * const local_vids	/* local vertex ids */
 	) {
-	struct h5t_fdata *t = f->t;
+	h5t_fdata_t *t = f->t;
 
 	_h5t_sort_local_vids ( f, local_vids, t->mesh_type );
 
@@ -396,7 +320,7 @@ _search_elem (
 		register int mid = (low + high) / 2;
 
 		h5_id_t local_eid = t->sorted_elems[0].items[mid];
-		h5_id_t *elem2 = t->elems_data.tets[local_eid].local_vids;
+		h5_id_t *elem2 = t->elems_ldta[local_eid].local_vids;
 		int diff = _vcmp_elems ( f, elem1, elem2 );
            	if ( diff < 0 )
                		high = mid - 1;
@@ -405,15 +329,7 @@ _search_elem (
            	else
                		return mid; // found
        	}
-	switch ( t->mesh_type ) {
-	case H5_OID_TETRAHEDRON:
-		return _h5t_error_local_tet_id_nexist ( f, local_vids );
-	case H5_OID_TRIANGLE:
-		return _h5t_error_local_triangle_id_nexist ( f, local_vids );
-	default:
-		return h5_error_internal( f, __FILE__, __func__, __LINE__ );
-	}
-       	return -(low+1);  // not found
+	return _h5t_error_local_elem_nexist ( f, local_vids );
 }
 
  /*!
@@ -425,7 +341,7 @@ h5t_get_local_eid (
 	h5_file_t *f,
 	h5_id_t * const local_vids	/* IN/OUT: local vertex id's */
 	) {
-	struct h5t_fdata *t = f->t;
+	h5t_fdata_t *t = f->t;
 
 	h5_id_t local_eid;
 	TRY ( local_eid = _search_elem ( f, local_vids ) );
@@ -488,17 +404,16 @@ h5t_map_local_eid2global (
 	h5_file_t *f,
 	const h5_id_t local_eid
 	) {
-	struct h5t_fdata *t = f->t;
+	h5t_fdata_t *t = f->t;
+
+	if ( local_eid < 0 || local_eid > t->num_elems[t->num_levels-1] )
+		return HANDLE_H5_OUT_OF_RANGE_ERR (
+			f, _h5t_oid_names[t->mesh_type], local_eid );
 
 	switch ( t->mesh_type ) {
 	case H5_OID_TETRAHEDRON:
-		if ( local_eid < 0 || local_eid > t->num_elems[t->num_levels-1] )
-			return HANDLE_H5_OUT_OF_RANGE_ERR ( f, "tet", local_eid );
 		return t->elems.tets[local_eid].global_eid;
 	case H5_OID_TRIANGLE:
-		if ( local_eid < 0 || local_eid > t->num_elems[t->num_levels-1] )
-			return HANDLE_H5_OUT_OF_RANGE_ERR (
-				f, "triangle", local_eid );
 		return t->elems.tris[local_eid].global_eid;
 	default:
 		return  h5_error_internal ( f, __FILE__, __func__, __LINE__ ); 
@@ -516,9 +431,6 @@ h5t_get_global_eid (
 	struct h5t_fdata *t = f->t;
 	h5_id_t local_vids[H5_MAX_VERTICES_PER_ELEM];
 
-	if ( t->vertices == NULL ) {
-		TRY ( _h5t_read_mesh ( f ) );
-	}
 	TRY ( h5t_map_global_vids2local (
 		f,
 		global_vids,
@@ -529,130 +441,6 @@ h5t_get_global_eid (
 	return h5t_map_local_eid2global ( f, local_eid );
 }
 
-static int
-_search_ith_vertex_in_elem (
-	h5_file_t * const f,
-	const int i,
-	h5_id_t	local_vid
-	) {
-	struct h5t_fdata *t = f->t;
-
-	register h5_id_t low = 0;
-	register h5_id_t high = t->sorted_elems[i].num_items - 1;
-	register h5_float64_t *vertex1 = t->vertices[local_vid].P;
-
-	while (low <= high) {
-		register int mid = (low + high) / 2;
-
-		h5_id_t local_eid = t->sorted_elems[i].items[mid];
-		h5_id_t local_vid2 = t->elems_data.tets[local_eid].local_vids[i];
-		h5_float64_t *vertex2 = t->vertices[local_vid2].P;
-		int diff = _cmp_vertices ( vertex1, vertex2 );
-
-           	if ( diff < 0 )
-               		high = mid - 1;
-           	else if ( diff > 0 )
-               		low = mid + 1;
-           	else
-               		return mid; // found
-       	}
-       	return -(low+1);  // not found
-}
-
-static h5_id_t
-_tetm_contain_triangle (
-	h5_file_t *f,
-	const h5_id_t * const local_vids,
-	int i,
-	h5_id_t local_eid
-	) {
-	h5t_fdata_t *t = f->t;
-
-	h5_id_t *local_vids_of_elem = t->elems_data.tets[local_eid].local_vids;
-	if ( i == 0 && 
-	     local_vids[1] == local_vids_of_elem[1] && 
-	     local_vids[2] == local_vids_of_elem[2]
-		) return 0;
-	else if ( i == 0 && 
-	     local_vids[1] == local_vids_of_elem[1] && 
-	     local_vids[2] == local_vids_of_elem[3]
-		) return 1;
-	else if ( i == 0 && 
-	     local_vids[1] == local_vids_of_elem[2] && 
-	     local_vids[2] == local_vids_of_elem[3]
-		) return 2;
-	else if ( i == 1 && 
-	     local_vids[1] == local_vids_of_elem[2] && 
-	     local_vids[2] == local_vids_of_elem[3]
-		) return 3;
-	return H5_NOK;
-}
-
-/*!
-  Search for triangle given by local vertex id in tetrahdral mesh.
-
-  \return unique local triangle id
- */
-h5_id_t
-_tetm_search_triangle (
-	h5_file_t *f,
-	h5_id_t * const local_vids
-	) {
-	struct h5t_fdata *t = f->t;
-
-	_h5t_sort_local_vids ( f, local_vids, 3 );
-
-	/*
-	  search for vid(tri,0) in the tuple of all 0th vertices of all tets
-	  if there is one:
-		take the smallest tet with vid(tri,0) == vid(tet,0)
-		loop over all tets with vid(tri,0) == vid(tet,0)
-		until we find a tet the triangle is belonging to.
-	  else
-		search for vid(tri,0) in the tuple of all 1st vertices of
-		all tets
-		if there is one:
-			take the smallest tet with
-			vid(tri,0) == vid(tet,0)
-			loop over all tets with
-			vid(tri,0) == vid(tet,0)
-			until we find a tet the triangle is belonging to.
-	*/
-
-	int i;
-	h5_id_t idx[2];
-	h5_id_t local_eid[2];
-	h5_id_t tidx[2];
-	for ( i = 0; i < 2; i++ ) {
-		idx[i] = _search_ith_vertex_in_elem ( f, i, local_vids[0] );
-
-		while ( idx[i] > 0 &&		/* get leftmost */
-			local_vids[0] == _get_local_vid_of_elem (
-				f, i, t->sorted_elems[0].items[idx[i]-1] ) )
-			idx[i]--;
-
-		do {
-			/* check whether triangle is in elem given by local id */
-			local_eid[i] = t->sorted_elems[i].items[idx[i]];
-			tidx[i] = _tetm_contain_triangle (
-				f, local_vids, i, local_eid[i] );
-			if ( tidx[i] >= 0 ) break;
-			idx[i]++;
-		} while ( local_vids[0] == _get_local_vid_of_elem (
-				  f, i, local_eid[i] ) );
-	}
-	if ( idx[0] < 0 && idx[1] < 0 ) return -1;
-	if ( idx[0] < 0 ) return _h5t_build_triangle_id ( tidx[1], local_eid[1] );
-	if ( idx[1] < 0 ) return _h5t_build_triangle_id ( tidx[0], local_eid[0] );
-
-	if ( _cmp_elems( f, local_eid[0], local_eid[1] ) < 0 )
-		return _h5t_build_triangle_id ( tidx[0], local_eid[0] );
-	else
-		return _h5t_build_triangle_id ( tidx[1], local_eid[1] );
-
-	return -1;
-}
-
 /*!
   
  */
@@ -663,10 +451,6 @@ h5t_get_global_triangle_id  (
 	) {
 	struct h5t_fdata *t = f->t;
 
-	if ( t->vertices == NULL ) {
-		TRY ( _h5t_read_mesh ( f ) );
-	}
-
 	switch ( t->mesh_type ) {
 	case H5_OID_TETRAHEDRON: {
 		h5_id_t local_vids[3];
@@ -693,17 +477,16 @@ h5t_get_local_triangle_id  (
 	h5_file_t * const f,
 	h5_id_t * const local_vids
 	) {
-	struct h5t_fdata *t = f->t;
-	if ( t->vertices == NULL ) {
-		TRY ( _h5t_read_mesh ( f ) );
-	}
+	h5t_fdata_t *t = f->t;
+
 	switch ( t->mesh_type ) {
 	case H5_OID_TETRAHEDRON: {
-		h5_id_t local_tid = _tetm_search_triangle ( f, local_vids );
-		if ( local_tid == -1 ) {
-			return _h5t_error_local_triangle_id_nexist( f, local_vids );
-		}
-		return local_tid;
+		h5_td_node_t *td;
+		TRY ( _h5t_find_td (
+			      f,
+			      &td,
+			      local_vids ) );
+		return td->value.items[0];
 	}
 	case H5_OID_TRIANGLE:
 		return h5t_get_local_eid ( f, local_vids );
@@ -712,6 +495,31 @@ h5t_get_local_triangle_id  (
 	}
 }
 
+h5_id_t
+h5t_get_local_triangle_id2 (
+	h5_file_t * const f,
+	h5_id_t face_id,
+	h5_id_t local_eid
+	) {
+	h5t_fdata_t *t = f->t;
+
+	switch ( t->mesh_type ) {
+	case H5_OID_TETRAHEDRON: {
+		h5_td_node_t *td;
+		TRY ( _h5t_find_td2 (
+			      f,
+			      &td,
+			      face_id,
+			      local_eid) );
+		return td->value.items[0];
+	}
+	case H5_OID_TRIANGLE:
+		return local_eid;
+	default:
+		return h5_error_internal ( f, __FILE__, __func__, __LINE__ ); 
+	}
+}
+
 /*!
   Get local element id for an element given by its global id.
 
@@ -817,117 +625,24 @@ _h5t_rebuild_global_2_local_map_of_elems (
 	h5_id_t local_eid = t->cur_level > 0 ? t->num_elems[t->cur_level-1] : 0;
 	h5_id_t num_elems = t->num_elems[t->num_levels-1];
 	h5_idmap_el_t *item = &t->map_elem_g2l.items[local_eid];
-
-	switch ( t->mesh_type ) {
-	case H5_OID_TETRAHEDRON: {
-		h5_tet_t *elem = &t->elems.tets[local_eid];
-		for ( ; local_eid < num_elems; local_eid++, item++, elem++ ) {
-			item->global_id = elem->global_eid; 
-			item->local_id = local_eid;
-			t->map_elem_g2l.num_items++;
-		}
-		break;
-	}
-	case H5_OID_TRIANGLE: {
-		h5_triangle_t *elem = &t->elems.tris[local_eid];
-		for ( ; local_eid < num_elems; local_eid++, item++, elem++ ) {
-			item->global_id = elem->global_eid; 
-			item->local_id = local_eid;
-			t->map_elem_g2l.num_items++;
-		}
-		break;
-	}
-	default:
-		return h5_error_internal( f, __FILE__, __func__, __LINE__ );
+	size_t offset = _h5t_sizeof_elem[t->mesh_type];
+	void *elemp = t->elems.data + local_eid*offset;
+	for ( ;
+	      local_eid < num_elems;
+	      local_eid++,
+		      item++,
+		      elemp+=offset ) {
+		h5_elem_t *elem = (h5_elem_t*)elemp;
+		
+		item->global_id = elem->global_eid; 
+		item->local_id = local_eid;
+		t->map_elem_g2l.num_items++;
 	}
 	_h5_sort_idmap ( &t->map_elem_g2l );
 
 	return H5_SUCCESS;
 }
 
-/*
-  setup structure "elems_data" with local ids for each element:
-  - translate the global vertex id's of each element to their
-    local id's
-  - translate the global parent id of each element to the
-    corresponding local id.
-*/
-h5_err_t
-_h5t_rebuild_elems_data (
-	h5_file_t * const f
-	) {
-	h5t_fdata_t *t = f->t;
-	h5_id_t local_eid = 0;
-	h5_id_t num_elems = t->num_elems[t->num_levels-1];
-	h5_id_t level_id = 0;
-	switch ( t->mesh_type ) {
-	case H5_OID_TETRAHEDRON: {
-		h5_tet_t *el;
-		h5_tet_data_t *el_data;
-
-		for ( local_eid=0, el=t->elems.tets, el_data=t->elems_data.tets;
-		      local_eid < num_elems;
-		      local_eid++, el++, el_data++ ) {
-			
-			TRY( h5t_map_global_vids2local (
-				     f,
-				     el->global_vids,
-				     t->mesh_type,
-				     el_data->local_vids
-				     ) );
-			if ( el->global_parent_eid >= 0 )
-				TRY ( el_data->local_parent_eid =
-				      h5t_map_global_eid2local (
-					      f,
-					      el->global_parent_eid ) );
-
-			if ( el->global_child_eid >= 0 )
-				TRY ( el_data->local_child_eid =
-				      h5t_map_global_eid2local (
-					      f,
-					      el->global_child_eid ) );
-
-			if ( local_eid >= t->num_elems[level_id] ) {
-				level_id++;
-			}
-			el_data->level_id = level_id;
-		}
-		break;
-	}
-	case H5_OID_TRIANGLE: {
-		h5_triangle_t *el;
-		h5_triangle_data_t *el_data;
-
-		for ( local_eid=0, el=t->elems.tris, el_data=t->elems_data.tris;
-		      local_eid < num_elems;
-		      local_eid++, el++, el_data++ ) {
-
-			TRY( h5t_map_global_vids2local (
-				     f,
-				     el->global_vids,
-				     t->mesh_type,
-				     el_data->local_vids
-				     ) );
-			if ( el->global_parent_eid >= 0 )
-				TRY ( el_data->local_parent_eid =
-				      h5t_map_global_eid2local (
-					      f,
-					      el->global_parent_eid ) );
-			if ( local_eid > t->num_elems_on_level[level_id] ) {
-				level_id++;
-			}
-			el_data->level_id = level_id;
-		}
-		break;
-	}
-	default:
-		return h5_error_internal (
-			f, __FILE__, __func__, __LINE__ );
-	}
-
-	return H5_SUCCESS;
-}
-
 /*!
   \param[in]	f		file handle
   \param[in]	local_id	local ID of entity
@@ -942,7 +657,7 @@ h5t_get_local_vids_of_entity (
 	h5t_fdata_t *t = f->t;
 	h5_id_t face_id = _h5t_get_face_id ( local_id );
 	h5_id_t local_eid = _h5t_get_elem_id ( local_id );
-	h5_tet_data_t	*tet_dta = &t->elems_data.tets[local_eid];
+	h5_elem_ldta_t	*tet_dta = &t->elems_ldta[local_eid];
 
 	switch ( _h5t_get_entity_type ( local_id ) ) {
 	case H5T_ELEM_TYPE_VERTEX: {
diff --git a/src/h5_core/h5t_map.h b/src/h5_core/h5t_map.h
index d65f948..876965e 100644
--- a/src/h5_core/h5t_map.h
+++ b/src/h5_core/h5t_map.h
@@ -69,6 +69,13 @@ h5t_get_local_triangle_id  (
 	h5_id_t * const local_vids
 	);
 
+h5_id_t
+h5t_get_local_triangle_id2 (
+	h5_file_t * const f,
+	h5_id_t face_id,
+	h5_id_t local_eid
+	);
+
 h5_id_t
 h5t_get_global_triangle_id (
 	h5_file_t * const f,
diff --git a/src/h5_core/h5t_map_private.h b/src/h5_core/h5t_map_private.h
index 7672adc..fa3030f 100644
--- a/src/h5_core/h5t_map_private.h
+++ b/src/h5_core/h5t_map_private.h
@@ -35,9 +35,4 @@ _h5t_rebuild_global_2_local_map_of_elems (
 	h5_file_t * const f
 	);
 
-h5_err_t
-_h5t_rebuild_elems_data (
-	h5_file_t * const f
-	);
-
 #endif
diff --git a/src/h5_core/h5t_openclose.c b/src/h5_core/h5t_openclose.c
index 3d1a7c7..0491c69 100644
--- a/src/h5_core/h5t_openclose.c
+++ b/src/h5_core/h5t_openclose.c
@@ -373,37 +373,33 @@ h5_err_t
 _h5t_open_meshes_group (
 	h5_file_t * const f
 	) {
-	struct h5t_fdata *t = f->t;
+	h5t_fdata_t *t = f->t;
 
 	if ( t->topo_gid < 0 ) {
-		h5_err_t h5err = _h5t_open_topo_group ( f );
-		if ( h5err < 0 ) return h5err;
+		TRY ( _h5t_open_topo_group ( f ) );
 	}
-	switch ( t->mesh_type) {
-	case H5_OID_TETRAHEDRON:
-		t->meshes_gid = _h5_open_group ( f, t->topo_gid, "TetMeshes" );
-		break;
-	case H5_OID_TRIANGLE:
-		t->meshes_gid = _h5_open_group ( f, t->topo_gid, "TriangleMeshes" );
-		break;
-	default:
-		t->meshes_gid = -1;
-	}
-	return (h5_err_t)t->meshes_gid;
+	TRY ( (t->meshes_gid = _h5_open_group (
+		       f,
+		       t->topo_gid,
+		       _h5t_meshes_grpnames[t->mesh_type] ) ) );
+
+	return H5_SUCCESS;
 }
 
 h5_err_t
 _h5t_open_mesh_group (
 	h5_file_t * const f
 	) {
-	struct h5t_fdata *t = f->t;
+	h5t_fdata_t *t = f->t;
 
 	if ( t->meshes_gid < 0 ) {
-		h5_err_t h5err = _h5t_open_meshes_group ( f );
-		if ( h5err < 0 ) return h5err;
+		TRY ( _h5t_open_meshes_group ( f ) );
 	}
-	t->mesh_gid = _h5_open_group ( f, t->meshes_gid, t->mesh_name );
-	return (h5_err_t)t->mesh_gid;
+	TRY ( ( t->mesh_gid = _h5_open_group (
+			f,
+			t->meshes_gid,
+			t->mesh_name ) ) );
+	return H5_SUCCESS;
 }
 
 /*
@@ -415,7 +411,7 @@ h5t_open_mesh (
 	h5_id_t id,
 	const h5_oid_t type
 	) {
-	struct h5t_fdata *t = f->t;
+	h5t_fdata_t *t = f->t;
 
 	TRY( _h5t_close_mesh ( f ) );
 
@@ -449,8 +445,8 @@ h5t_open_mesh (
 	t->cur_mesh = id;
 
 	if ( id != t->num_meshes ) {	/* open existing */
-		t->num_levels = h5t_get_num_levels ( f );
-		if ( t->num_levels < 0 ) return t->num_levels;
+		TRY ( _h5t_read_mesh ( f ) );
+
 	} else {			/* append new */
 		t->num_meshes++;
 		t->mesh_changed = id;
@@ -486,8 +482,8 @@ _release_memory (
 	_h5_free ( f, t->elems.data );
 	t->elems.data = NULL;
 	_h5_free ( f, t->num_elems );
-	_h5_free ( f, t->elems_data.data );
-	t->elems_data.data = NULL;
+	_h5_free ( f, t->elems_ldta );
+	t->elems_ldta = NULL;
 	_h5_free ( f, t->num_elems_on_level );
 	t->num_elems_on_level = NULL;
 	_h5_free ( f, t->map_elem_g2l.items );
diff --git a/src/h5_core/h5t_readwrite.c b/src/h5_core/h5t_readwrite.c
index f526327..69d6104 100644
--- a/src/h5_core/h5t_readwrite.c
+++ b/src/h5_core/h5t_readwrite.c
@@ -108,6 +108,28 @@ _h5t_write_mesh (
 	return H5_SUCCESS;
 }
 
+static h5_size_t
+_read_num_levels (
+	h5_file_t * f
+	) {
+	h5t_fdata_t *t = f->t;
+	hid_t dataset_id;
+	hid_t diskspace_id;
+	hssize_t size;
+
+	if ( t->cur_mesh < 0 ) {
+		return _h5t_error_undef_mesh ( f );
+	}
+	TRY ( dataset_id = _h5_open_dataset ( f, t->mesh_gid, "NumVertices" ) );
+	TRY ( diskspace_id = _h5_get_dataset_space ( f, dataset_id ) );
+	TRY ( size = _h5_get_npoints_of_space ( f, diskspace_id ) );
+	TRY ( _h5_close_dataspace( f, diskspace_id ) );
+
+	t->num_levels = size;
+	return size;
+}
+
+
 static hid_t
 _open_mem_space_vertices (
 	h5_file_t * const f,
@@ -124,8 +146,8 @@ _open_file_space_vertices (
 	return H5S_ALL;
 }
 
-h5_err_t
-_h5t_read_num_vertices (
+static h5_err_t
+_read_num_vertices (
 	h5_file_t * const f
 	) {
 	struct h5t_fdata *t = f->t;
@@ -146,18 +168,12 @@ _h5t_read_num_vertices (
 	return H5_SUCCESS;
 }
 
-h5_err_t
-_h5t_read_vertices (
+static h5_err_t
+_read_vertices (
 	h5_file_t * f
 	) {
 	struct h5t_fdata *t = f->t;
 
- 	if ( t->mesh_gid < 0 ) {
-		TRY( _h5t_open_mesh_group ( f ) );
-	}
-	if ( t->num_vertices == NULL ) {
-		TRY( _h5t_read_num_vertices ( f ) );
-	}
 
 	TRY( _h5t_alloc_num_vertices ( f, t->num_vertices[t->num_levels-1] ) );
 	TRY( _h5_read (
@@ -175,8 +191,8 @@ _h5t_read_vertices (
 
 
 
-h5_err_t
-_h5t_read_num_elems (
+static h5_err_t
+_read_num_elems (
 	h5_file_t * const f
 	) {
 	struct h5t_fdata *t = f->t;
@@ -222,19 +238,62 @@ _open_file_space_elems (
 	return H5S_ALL;
 }
 
-h5_err_t
-_h5t_read_elems (
+/*
+  setup structure "elems_data" with local ids for each element:
+  - translate the global vertex id's of each element to their
+    local id's
+  - translate the global parent id of each element to the
+    corresponding local id.
+*/
+static h5_err_t
+_build_elems_ldta (
+	h5_file_t * const f
+	) {
+	h5t_fdata_t *t = f->t;
+	h5_id_t local_eid = 0;
+	h5_id_t num_elems = t->num_elems[t->num_levels-1];
+	h5_id_t level_id = 0;
+
+	void *elp = t->elems.data;
+	h5_elem_t *el;
+	h5_elem_ldta_t *el_data = t->elems_ldta;
+	
+	for ( local_eid=0;
+	      local_eid < num_elems;
+	      local_eid++, elp+=_h5t_sizeof_elem[t->mesh_type], el_data++ ) {
+		el = (h5_elem_t*)elp;
+		TRY( h5t_map_global_vids2local (
+			     f,
+			     el->global_vids,
+			     t->mesh_type,
+			     el_data->local_vids
+			     ) );
+		if ( el->global_parent_eid >= 0 )
+			TRY ( el_data->local_parent_eid =
+			      h5t_map_global_eid2local (
+				      f,
+				      el->global_parent_eid ) );
+		
+		if ( el->global_child_eid >= 0 )
+			TRY ( el_data->local_child_eid =
+			      h5t_map_global_eid2local (
+				      f,
+				      el->global_child_eid ) );
+		
+		if ( local_eid >= t->num_elems[level_id] ) {
+			level_id++;
+		}
+		el_data->level_id = level_id;
+	}
+
+	return H5_SUCCESS;
+}
+
+static h5_err_t
+_read_elems (
 	h5_file_t * f
 	) {
-	struct h5t_fdata *t = f->t;
-
- 	if ( t->mesh_gid < 0 ) {
-		TRY( _h5t_open_mesh_group ( f ) );
-	}
-
-	if ( t->num_elems == NULL ) {
-		TRY( _h5t_read_num_elems ( f ) );
-	}
+	h5t_fdata_t *t = f->t;
 
 	TRY( _h5t_alloc_num_elems ( f, 0, t->num_elems[t->num_levels-1] ) );
 	TRY( _h5_read (
@@ -247,7 +306,7 @@ _h5t_read_elems (
 
 	TRY ( _h5t_sort_elems ( f ) );
 	TRY ( _h5t_rebuild_global_2_local_map_of_elems ( f ) );
-	TRY ( _h5t_rebuild_elems_data ( f ) );
+	TRY ( _build_elems_ldta ( f ) );
 	TRY ( _h5t_rebuild_adj_data ( f ) );
 	return H5_SUCCESS;
 }
@@ -256,10 +315,14 @@ h5_err_t
 _h5t_read_mesh (
 	h5_file_t *f
 	) {
-
-	TRY ( _h5t_read_vertices ( f ) );
-	TRY ( _h5t_read_elems ( f ) );
-
+ 	if ( f->t->mesh_gid < 0 ) {
+		TRY( _h5t_open_mesh_group ( f ) );
+	}
+	TRY ( _read_num_levels ( f ) );
+	TRY ( _read_num_vertices ( f ) );
+	TRY ( _read_num_elems ( f ) );
+	TRY ( _read_vertices ( f ) );
+	TRY ( _read_elems ( f ) );
 	return H5_SUCCESS;
 }
 
diff --git a/src/h5_core/h5t_readwrite.h b/src/h5_core/h5t_readwrite.h
index e20d093..ffcaba9 100644
--- a/src/h5_core/h5t_readwrite.h
+++ b/src/h5_core/h5t_readwrite.h
@@ -1,19 +1,4 @@
 #ifndef __H5T_READWRITE_H
 #define __H5T_READWRITE_H
 
-h5_err_t
-_h5t_write_mesh (
-	h5_file_t * f
-	);
-
-h5_err_t
-_h5t_read_vertices (
-	h5_file_t * f
-	);
-
-h5_err_t
-_h5t_read_elems (
-	h5_file_t * f
-	);
-
 #endif
diff --git a/src/h5_core/h5t_readwrite_private.h b/src/h5_core/h5t_readwrite_private.h
index 5b016f8..feacedd 100644
--- a/src/h5_core/h5t_readwrite_private.h
+++ b/src/h5_core/h5t_readwrite_private.h
@@ -4,26 +4,21 @@
 h5_err_t
 _h5t_write_obj (
 	h5_file_t * f,
-	const hid_t	gid,
-	const hsize_t  current_dims,
-	const hsize_t  max_dims,
-	const hid_t    tid,
+	const hid_t gid,
+	const hsize_t current_dims,
+	const hsize_t max_dims,
+	const hid_t tid,
 	const void * const object,
 	const char * const dsname
 	);
 
 h5_err_t
 _h5t_read_mesh (
-	h5_file_t *f
-	);
-
-h5_err_t
-_h5t_read_num_elems (
 	h5_file_t * const f
 	);
 
 h5_err_t
-_h5t_read_num_vertices (
+_h5t_write_mesh (
 	h5_file_t * const f
 	);
 
diff --git a/src/h5_core/h5t_storemesh.c b/src/h5_core/h5t_storemesh.c
index b5b4108..8fb0e56 100644
--- a/src/h5_core/h5t_storemesh.c
+++ b/src/h5_core/h5t_storemesh.c
@@ -56,14 +56,45 @@ _h5t_assign_global_vertex_ids (
 }
 
 /*!
- Assign unique global id's to elements.
-
- Nothing to do in serial case.
+ Assign unique global IDs to new elements.
 */
-h5_err_t
-_h5t_assign_global_elem_ids (
+static h5_err_t
+_assign_global_elem_ids (
 	h5_file_t * const f
 	) {
+	h5t_fdata_t *t = f->t;
+	h5_id_t local_eid;
+
+	if ( t->cur_level < 0 ) return H5_SUCCESS; /* no level defined */
+
+	/*
+	  simple in serial runs: global_id = local_id
+	*/
+	for ( local_eid = (t->cur_level == 0) ? 0 : t->num_elems[t->cur_level-1];
+	      local_eid < t->num_elems[t->cur_level];
+	      local_eid++ ) {
+		h5_elem_t *elem;
+		h5_elem_ldta_t *elem_ldta = &t->elems_ldta[local_eid];
+		switch ( t->mesh_type ) {
+		case H5_OID_TETRAHEDRON:
+			elem = (h5_elem_t*)&t->elems.tets[local_eid];
+			break;
+		case H5_OID_TRIANGLE:
+			elem = (h5_elem_t*)&t->elems.tris[local_eid];
+			break;
+		default:
+			return h5_error_internal (
+				f, __FILE__, __func__, __LINE__ );
+		}
+		elem->global_eid = local_eid;
+		elem->global_parent_eid = elem_ldta->local_parent_eid;
+		elem->global_child_eid = elem_ldta->local_child_eid;
+		int i;
+		for ( i = 0; i < t->mesh_type; i++ ) {
+			elem->global_vids[i] = elem_ldta->local_vids[i];
+		}
+	}
+
 	return H5_SUCCESS;
 }
 
@@ -199,34 +230,49 @@ _h5t_alloc_num_elems (
 	) {
 	h5t_fdata_t *t = f->t;
 	size_t sizeof_elem = 0;
-	size_t sizeof_lelem = 0;
 
-	switch ( t->mesh_type ) {
-	case H5_OID_TETRAHEDRON:
-		sizeof_elem = sizeof ( t->elems.tets[0] );
-		sizeof_lelem = sizeof ( t->elems_data.tets[0] );
-		break;
-	case H5_OID_TRIANGLE:
-		sizeof_elem = sizeof ( t->elems.tris[0] );
-		sizeof_lelem = sizeof ( t->elems_data.tris[0] );
-		break;
-	default:
-		return h5_error_internal (
-			f, __FILE__, __func__, __LINE__ );
+	/* allocl mem for elements */
+	TRY ( t->elems.data = _h5_alloc (
+		      f,
+		      t->elems.data,
+		      new_num_elems * _h5t_sizeof_elem[t->mesh_type] ) );
+	memset (
+		t->elems.data+cur_num_elems*sizeof_elem,
+		-1,
+		(new_num_elems-cur_num_elems)*sizeof_elem );
+
+	/* alloc mem for local data of elements */
+	TRY ( t->elems_ldta = _h5_alloc (
+		      f,
+		      t->elems_ldta,
+		      new_num_elems * sizeof ( t->elems_ldta[0] ) ) );
+	memset (
+		t->elems_ldta+cur_num_elems*sizeof ( t->elems_ldta[0] ),
+		-1,
+		(new_num_elems-cur_num_elems)*sizeof ( t->elems_ldta[0] ) );
+
+	/* alloc mem for local vertex IDs of elements */
+	TRY ( t->elems_lvids = _h5_alloc (
+		      f,
+		      t->elems_lvids,
+		      new_num_elems*sizeof(t->elems_lvids[0])*t->mesh_type ) );
+	memset (
+		t->elems_lvids+cur_num_elems*sizeof(t->elems_lvids[0])*t->mesh_type,
+		-1,
+		(new_num_elems-cur_num_elems)*sizeof(t->elems_lvids[0])*t->mesh_type );
+
+	/* re-init pointer to local vertex id in local data structure */
+	int offset = t->mesh_type;
+	h5_id_t *p = t->elems_lvids;
+	h5_id_t id;
+	for ( id = 0; id < new_num_elems; id++, p+=offset ) {
+		t->elems_ldta[id].local_vids = p;
 	}
 
-	size_t size = new_num_elems * sizeof_elem;
-	TRY ( t->elems.data = _h5_alloc ( f, t->elems.data, size ) );
+	/* alloc mem for global to local ID mapping */
+	TRY ( _h5_alloc_idmap ( f, &t->map_elem_g2l, new_num_elems ) );
 
-	size = new_num_elems * sizeof_lelem;
-	TRY ( t->elems_data.data = _h5_alloc ( f, t->elems_data.data, size ) );
-
-	memset (
-		t->elems_data.data+cur_num_elems*sizeof_lelem,
-		-1,
-		(new_num_elems-cur_num_elems) * sizeof_lelem );
-
-	return  _h5_alloc_idmap ( f, &t->map_elem_g2l, new_num_elems );
+	return  H5_SUCCESS;
 }
 
 h5_err_t
@@ -285,15 +331,7 @@ h5t_store_elem    (
 			local_parent_eid );
 	}
 
-	switch ( t->mesh_type ) {
-	case H5_OID_TETRAHEDRON:
-		return _h5t_store_tet ( f, local_parent_eid, local_vids );
-	case H5_OID_TRIANGLE:
-		return _h5t_store_triangle ( f, local_parent_eid, local_vids );
-	default:
-		return h5_error_internal (
-			f, __FILE__, __func__, __LINE__ );
-	}
+	return _h5t_store_elem ( f, local_parent_eid, local_vids );
 }
 
 /*!
@@ -304,50 +342,23 @@ h5t_store_elem    (
   \param[in]	local_vids	Local vertex id's defining the tetrahedron.
  */
 h5_id_t
-_h5t_store_tet (
+_h5t_store_elem (
 	h5_file_t * const f,
 	const h5_id_t local_parent_eid,
-	const h5_id_t local_vids[4]
+	const h5_id_t *local_vids
 	) {
 
-	struct h5t_fdata *t = f->t;
-	t->level_changed = 1;	
-	h5_id_t local_eid = ++t->last_stored_eid;
-	h5_tetrahedron_t *tet = &t->elems.tets[local_eid];
-	h5_tet_data_t *tet_data = &t->elems_data.tets[local_eid];
-	tet->global_eid = local_eid;
-	tet->global_parent_eid = local_parent_eid;
-	tet->global_child_eid = -1;
-
-	memcpy ( &tet->global_vids, local_vids, sizeof ( tet->global_vids ) );
-	_h5t_sort_local_vids ( f, tet->global_vids, 4 );
-	memcpy ( &tet_data->local_vids, &tet->global_vids,
-		 sizeof ( tet->global_vids ) );
-
-	return local_eid;
-}
-
-
-h5_id_t
-_h5t_store_triangle (
-	h5_file_t * const f,
-	const h5_id_t local_parent_eid,
-	const h5_id_t vids[3]
-	) {
-
-	struct h5t_fdata *t = f->t;
+	h5t_fdata_t *t = f->t;
 	t->level_changed = 1;
 	h5_id_t local_eid = ++t->last_stored_eid;
-	h5_triangle_t *tri = &t->elems.tris[local_eid];
-	h5_triangle_data_t *tri_data = &t->elems_data.tris[local_eid];
-	tri->global_eid = local_eid;
-	tri->global_parent_eid = local_parent_eid;
-	tri->global_child_eid = -1;
+	h5_elem_ldta_t *elem_ldta = &t->elems_ldta[local_eid];
 
-	memcpy ( &tri->global_vids, vids, sizeof ( tri->global_vids ) );
-	_h5t_sort_local_vids ( f, tri->global_vids, 3 );
-	memcpy ( &tri_data->local_vids, &tri->global_vids,
-		 sizeof ( tri->global_vids ) );
+	elem_ldta->local_parent_eid = local_parent_eid;
+	elem_ldta->local_child_eid = -1;
+	elem_ldta->level_id = t->cur_level;
+	memcpy ( elem_ldta->local_vids, local_vids,
+		 sizeof (*local_vids) * t->mesh_type );
+	_h5t_sort_local_vids ( f, elem_ldta->local_vids, t->mesh_type );
 
 	return local_eid;
 }
@@ -360,10 +371,9 @@ h5t_end_store_elems (
 	t->storing_data = 0;
 
 	t->num_elems[t->cur_level] = t->last_stored_eid+1;
-	TRY ( _h5t_assign_global_elem_ids ( f ) );
+	TRY ( _assign_global_elem_ids ( f ) );
 	TRY ( _h5t_sort_elems ( f ) );
 	TRY ( _h5t_rebuild_global_2_local_map_of_elems ( f ) );
-	TRY ( _h5t_rebuild_elems_data ( f ) );
 
 	return H5_SUCCESS;
 }
@@ -474,46 +484,46 @@ _h5t_refine_triangle (
 
 	local_vids[0] = _h5t_bisect_edge(
 		f,
-		t->elems_data.tris[local_eid].local_vids[0],
-		t->elems_data.tris[local_eid].local_vids[1] );
+		t->elems_ldta[local_eid].local_vids[0],
+		t->elems_ldta[local_eid].local_vids[1] );
 	local_vids[1] = _h5t_bisect_edge(
 		f,
-		t->elems_data.tris[local_eid].local_vids[0],
-		t->elems_data.tris[local_eid].local_vids[2] );
+		t->elems_ldta[local_eid].local_vids[0],
+		t->elems_ldta[local_eid].local_vids[2] );
 	local_vids[2] = _h5t_bisect_edge(
 		f,
-		t->elems_data.tris[local_eid].local_vids[1],
-		t->elems_data.tris[local_eid].local_vids[2] );
+		t->elems_ldta[local_eid].local_vids[1],
+		t->elems_ldta[local_eid].local_vids[2] );
 
 
 	h5_id_t elem_local_vids[4];
 
 	/* 0 */
-	elem_local_vids[0] = t->elems_data.tets[local_eid].local_vids[0];
+	elem_local_vids[0] = t->elems_ldta[local_eid].local_vids[0];
 	elem_local_vids[1] = local_vids[0];
 	elem_local_vids[2] = local_vids[1];
-	TRY ( local_child_eid = _h5t_store_triangle (
+	TRY ( local_child_eid = _h5t_store_elem (
 		      f,
 		      local_eid, elem_local_vids ) );
 	if ( local_eid >= 0 ) {
 		t->elems.tris[local_eid].global_child_eid = local_child_eid;
-		t->elems_data.tris[local_eid].local_child_eid = local_child_eid;
+		t->elems_ldta[local_eid].local_child_eid = local_child_eid;
 		t->num_elems_on_level[t->cur_level]--;
 	}
 
 	/* 1 */
-	elem_local_vids[0] = t->elems_data.tets[local_eid].local_vids[1];
+	elem_local_vids[0] = t->elems_ldta[local_eid].local_vids[1];
 	elem_local_vids[1] = local_vids[0];
 	elem_local_vids[2] = local_vids[2];
-	TRY ( _h5t_store_triangle (
+	TRY ( _h5t_store_elem (
 		      f,
 		      local_eid, elem_local_vids ) );
 
 	/* 2 */
-	elem_local_vids[0] = t->elems_data.tets[local_eid].local_vids[2];
+	elem_local_vids[0] = t->elems_ldta[local_eid].local_vids[2];
 	elem_local_vids[1] = local_vids[1];
 	elem_local_vids[2] = local_vids[2];
-	TRY ( _h5t_store_triangle (
+	TRY ( _h5t_store_elem (
 		      f,
 		      local_eid, elem_local_vids ) );
 
@@ -521,7 +531,7 @@ _h5t_refine_triangle (
 	elem_local_vids[0] = local_vids[0];
 	elem_local_vids[1] = local_vids[1];
 	elem_local_vids[2] = local_vids[2];
-	TRY ( _h5t_store_triangle (
+	TRY ( _h5t_store_elem (
 		      f,
 		      local_eid, elem_local_vids ) );
 
@@ -548,34 +558,34 @@ _h5t_refine_tet (
 			H5_ERR_INVAL,
 			"Tetrahedron %lld already refined.",
 			local_eid );
-	local_vids[0] = t->elems_data.tets[local_eid].local_vids[0];
-	local_vids[1] = t->elems_data.tets[local_eid].local_vids[1];
-	local_vids[2] = t->elems_data.tets[local_eid].local_vids[2];
-	local_vids[3] = t->elems_data.tets[local_eid].local_vids[3];
+	local_vids[0] = t->elems_ldta[local_eid].local_vids[0];
+	local_vids[1] = t->elems_ldta[local_eid].local_vids[1];
+	local_vids[2] = t->elems_ldta[local_eid].local_vids[2];
+	local_vids[3] = t->elems_ldta[local_eid].local_vids[3];
 	local_vids[4] = _h5t_bisect_edge(
 		f,
-		t->elems_data.tets[local_eid].local_vids[0],
-		t->elems_data.tets[local_eid].local_vids[1] );
+		t->elems_ldta[local_eid].local_vids[0],
+		t->elems_ldta[local_eid].local_vids[1] );
 	local_vids[5] = _h5t_bisect_edge(
 		f,
-		t->elems_data.tets[local_eid].local_vids[0],
-		t->elems_data.tets[local_eid].local_vids[2] );
+		t->elems_ldta[local_eid].local_vids[0],
+		t->elems_ldta[local_eid].local_vids[2] );
 	local_vids[6] = _h5t_bisect_edge(
 		f,
-		t->elems_data.tets[local_eid].local_vids[0],
-		t->elems_data.tets[local_eid].local_vids[3] );
+		t->elems_ldta[local_eid].local_vids[0],
+		t->elems_ldta[local_eid].local_vids[3] );
 	local_vids[7] = _h5t_bisect_edge(
 		f,
-		t->elems_data.tets[local_eid].local_vids[1],
-		t->elems_data.tets[local_eid].local_vids[2] );
+		t->elems_ldta[local_eid].local_vids[1],
+		t->elems_ldta[local_eid].local_vids[2] );
 	local_vids[8] = _h5t_bisect_edge(
 		f,
-		t->elems_data.tets[local_eid].local_vids[1],
-		t->elems_data.tets[local_eid].local_vids[3] );
+		t->elems_ldta[local_eid].local_vids[1],
+		t->elems_ldta[local_eid].local_vids[3] );
 	local_vids[9] = _h5t_bisect_edge(
 		f,
-		t->elems_data.tets[local_eid].local_vids[2],
-		t->elems_data.tets[local_eid].local_vids[3] );
+		t->elems_ldta[local_eid].local_vids[2],
+		t->elems_ldta[local_eid].local_vids[3] );
 
 	/* 
 	   add new tets
@@ -587,7 +597,7 @@ _h5t_refine_tet (
 	new_tet_local_vids[1] = local_vids[6];  // (03)
 	new_tet_local_vids[2] = local_vids[5];  // (02)
 	new_tet_local_vids[3] = local_vids[4];  // (01)
-	TRY ( local_child_eid = _h5t_store_tet (
+	TRY ( local_child_eid = _h5t_store_elem (
 		      f, local_eid, new_tet_local_vids ) );
 
 	/* 1 */
@@ -595,52 +605,52 @@ _h5t_refine_tet (
 	new_tet_local_vids[1] = local_vids[8];  // (13)
 	new_tet_local_vids[2] = local_vids[7];  // (12)
 	new_tet_local_vids[3] = local_vids[1];
-	TRY ( _h5t_store_tet ( f, local_eid, new_tet_local_vids ) );
+	TRY ( _h5t_store_elem ( f, local_eid, new_tet_local_vids ) );
 
 	/* 2 */
 	new_tet_local_vids[0] = local_vids[5];  // (02)
 	new_tet_local_vids[1] = local_vids[9];  // (23)
 	new_tet_local_vids[2] = local_vids[2];
 	new_tet_local_vids[3] = local_vids[7];  // (12)
-	TRY ( _h5t_store_tet ( f, local_eid, new_tet_local_vids ) );
+	TRY ( _h5t_store_elem ( f, local_eid, new_tet_local_vids ) );
 
 	/* 3 */
 	new_tet_local_vids[0] = local_vids[6];  // (03)
 	new_tet_local_vids[1] = local_vids[3];
 	new_tet_local_vids[2] = local_vids[9];  // (23)
 	new_tet_local_vids[3] = local_vids[8];  // (13)
-	TRY ( _h5t_store_tet ( f, local_eid, new_tet_local_vids ) );
+	TRY ( _h5t_store_elem ( f, local_eid, new_tet_local_vids ) );
 
 	/* 4 */
 	new_tet_local_vids[0] = local_vids[6];  // (03)
 	new_tet_local_vids[1] = local_vids[5];  // (02)
 	new_tet_local_vids[2] = local_vids[4];  // (01)
 	new_tet_local_vids[3] = local_vids[8];  // (13)
-	TRY ( _h5t_store_tet ( f, local_eid, new_tet_local_vids ) );
+	TRY ( _h5t_store_elem ( f, local_eid, new_tet_local_vids ) );
 
 	/* 5 */
 	new_tet_local_vids[0] = local_vids[5];  // (02)
 	new_tet_local_vids[1] = local_vids[4];  // (01)
 	new_tet_local_vids[2] = local_vids[8];  // (13)
 	new_tet_local_vids[3] = local_vids[7];  // (12)
-	TRY ( _h5t_store_tet ( f, local_eid, new_tet_local_vids ) );
+	TRY ( _h5t_store_elem ( f, local_eid, new_tet_local_vids ) );
 
 	/* 6 */
 	new_tet_local_vids[0] = local_vids[6];  // (03)
 	new_tet_local_vids[1] = local_vids[5];  // (02)
 	new_tet_local_vids[2] = local_vids[9];  // (23)
 	new_tet_local_vids[3] = local_vids[8];  // (13)
-	TRY ( _h5t_store_tet ( f, local_eid, new_tet_local_vids ) );
+	TRY ( _h5t_store_elem ( f, local_eid, new_tet_local_vids ) );
 
 	/* 7 */
 	new_tet_local_vids[0] = local_vids[5];  // (02)
 	new_tet_local_vids[1] = local_vids[9];  // (23)
 	new_tet_local_vids[2] = local_vids[8];  // (13)
 	new_tet_local_vids[3] = local_vids[7];  // (12)
-	TRY ( _h5t_store_tet ( f, local_eid, new_tet_local_vids ) );
+	TRY ( _h5t_store_elem ( f, local_eid, new_tet_local_vids ) );
 
 	t->elems.tets[local_eid].global_child_eid = local_child_eid;
-	t->elems_data.tets[local_eid].local_child_eid = local_child_eid;
+	t->elems_ldta[local_eid].local_child_eid = local_child_eid;
 	t->num_elems_on_level[t->cur_level]--;
 
 	return local_child_eid;
diff --git a/src/h5_core/h5t_storemesh_private.h b/src/h5_core/h5t_storemesh_private.h
index ef9ff7e..ed62b8a 100644
--- a/src/h5_core/h5t_storemesh_private.h
+++ b/src/h5_core/h5t_storemesh_private.h
@@ -15,17 +15,10 @@ _h5t_alloc_num_elems (
 	);
 
 h5_id_t
-_h5t_store_triangle (
+_h5t_store_elem (
 	h5_file_t * const f,
 	const h5_id_t local_parent_eid,
-	const h5_id_t vids[3]
-	);
-
-h5_id_t
-_h5t_store_tet (
-	h5_file_t * const f,
-	const h5_id_t local_parent_eid,
-	const h5_id_t vids[4]
+	const h5_id_t vids[]
 	);
 
 
diff --git a/src/h5_core/h5t_types_private.h b/src/h5_core/h5t_types_private.h
index 74a8b42..895847c 100644
--- a/src/h5_core/h5t_types_private.h
+++ b/src/h5_core/h5t_types_private.h
@@ -32,7 +32,7 @@ struct h5_tetrahedron {
 	h5_4id_t	global_vids;
 };
 
-struct h5_element {
+struct h5_elem {
 	h5_id_t		global_eid;
 	h5_id_t		global_parent_eid;
 	h5_id_t		global_child_eid;
@@ -41,31 +41,15 @@ struct h5_element {
 
 typedef struct h5_tetrahedron	h5_tetrahedron_t;
 typedef struct h5_tetrahedron	h5_tet_t;
-typedef struct h5_element	h5_element_t;
+typedef struct h5_elem		h5_elem_t;
 
-struct h5_triangle_data {
+struct h5_elem_ldta {
 	h5_id_t		local_parent_eid;
 	h5_id_t		local_child_eid;
 	h5_id_t		level_id;
-	h5_3id_t	local_vids;
+	h5_id_t		*local_vids;
 };
-typedef struct h5_triangle_data h5_triangle_data_t;
-
-struct h5_tet_data {
-	h5_id_t		local_parent_eid;
-	h5_id_t		local_child_eid;
-	h5_id_t		level_id;
-	h5_4id_t	local_vids;
-};
-typedef struct h5_tet_data	h5_tet_data_t;
-
-struct h5_element_data {
-	h5_id_t		local_parent_eid;
-	h5_id_t		local_child_eid;
-	h5_id_t		level_id;
-	h5_id_t		local_vids[1];
-};
-typedef struct h5_element_data	h5_element_data_t;
+typedef struct h5_elem_ldta	h5_elem_ldta_t;
 
 
 union h5_elems {
@@ -75,12 +59,6 @@ union h5_elems {
 };
 typedef union h5_elems h5_elems_t;
 
-union h5_elems_data {
-	h5_tet_data_t		*tets;
-	h5_triangle_data_t	*tris;
-	void			*data;
-};
-typedef union h5_elems_data h5_elems_data_t;
 
 /*
   information about HDF5 dataset
@@ -220,7 +198,8 @@ struct h5t_fdata {
 
 	/*** Elements ***/
 	h5_elems_t	elems;
-	h5_elems_data_t	elems_data;	/* local, per element data */
+	h5_elem_ldta_t	*elems_ldta;	/* local, per element data */
+	h5_id_t		*elems_lvids;
 	h5_size_t	*num_elems;
 	h5_size_t	*num_elems_on_level;
 	h5_idmap_t	map_elem_g2l;	/* map global id to local id */