diff --git a/src/BuildTiles/Main/construct.cxx b/src/BuildTiles/Main/construct.cxx
index 607bd6e0..4eb35cc7 100644
--- a/src/BuildTiles/Main/construct.cxx
+++ b/src/BuildTiles/Main/construct.cxx
@@ -51,8 +51,7 @@
 
 using std::string;
 
-//double gSnap = 0.00000001;      // approx 1 mm
-double gSnap = 0.0000002;      // approx 2 cm
+double gSnap = 0.00000001;      // approx 1 mm
 
 static const double cover_size = 1.0 / 120.0;
 static const double half_cover_size = cover_size * 0.5;
@@ -1853,7 +1852,7 @@ void TGConstruct::TesselatePolys( void )
                         ": id = " << id );
 
 //              TGPolygon tri = polygon_tesselate_alt_with_extra( poly, poly_extra, false );
-                TGPolygon tri = polygon_tesselate_alt_with_extra( poly, poly_extra, false );
+                TGPolygon tri = polygon_tesselate_alt_with_extra_cgal( poly, poly_extra, false );
 
                 // ensure all added nodes are accounted for
                 for (int k=0; k< tri.contours(); k++) {
diff --git a/src/Lib/Geometry/poly_cgal.cxx b/src/Lib/Geometry/poly_cgal.cxx
index c20b822b..b5be6bee 100644
--- a/src/Lib/Geometry/poly_cgal.cxx
+++ b/src/Lib/Geometry/poly_cgal.cxx
@@ -114,7 +114,15 @@ TGPolygon polygon_tesselate_alt_with_extra_cgal( TGPolygon &p, const point_list&
         return result;
     }
 
-    // insert each polygon into the triangulation
+    // First, insert the extra points
+    std::vector<Point> points;
+    points.reserve(extra_nodes.size());
+    for (unsigned int n = 0; n < extra_nodes.size(); n++) {
+        points.push_back( Point(extra_nodes[n].x(), extra_nodes[n].y()) );     
+    }
+    cdt.insert(points.begin(), points.end());
+    
+    // then insert each polygon as a constraint into the triangulation
     for (int c = 0; c < p.contours(); c++) {
         point_list contour = p.get_contour( c );
         Polygon_2  poly;
@@ -148,4 +156,4 @@ TGPolygon polygon_tesselate_alt_with_extra_cgal( TGPolygon &p, const point_list&
     }
 
     return result;
-}
\ No newline at end of file
+}