diff --git a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/remesh_planar_patches.h b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/remesh_planar_patches.h
index 784b317c41d..fd007d5915f 100644
--- a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/remesh_planar_patches.h
+++ b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/remesh_planar_patches.h
@@ -57,7 +57,7 @@ struct Face_map
   friend
   void put(Face_map m, key_type k, value_type v)
   {
-    put(m.pm, v, m.face_ids[k]);
+    put(m.pm, v, static_cast<key_type>(m.face_ids[k]));
   }
 
   PM pm;
@@ -604,6 +604,7 @@ bool decimate_impl(const TriangleMesh& tm,
   typedef typename graph_traits::vertex_descriptor vertex_descriptor;
   typedef typename graph_traits::face_descriptor face_descriptor;
   typedef std::pair<std::size_t, std::size_t> Id_pair;
+  typedef typename boost::property_traits<FaceCCIdMap>::value_type PID;
 
   // compute the new mesh
   std::vector< std::vector< boost::container::small_vector<std::size_t,3> > > faces_per_cc(nb_corners_and_nb_cc.second);
@@ -699,7 +700,7 @@ bool decimate_impl(const TriangleMesh& tm,
           //      we could work on the graph on constraint and recover only the orientation
           //      of the edge. To be done if someone find it too slow.
           std::vector<halfedge_descriptor> hborders;
-          CGAL::Face_filtered_graph<TriangleMesh> ffg(tm, cc_id, face_cc_ids);
+          CGAL::Face_filtered_graph<TriangleMesh> ffg(tm, static_cast<PID>(cc_id), face_cc_ids);
           extract_boundary_cycles(ffg, std::back_inserter(hborders));
 
           if (hborders.size()==1)
@@ -738,7 +739,7 @@ bool decimate_impl(const TriangleMesh& tm,
 #endif
           all_patches_successfully_remeshed = false;
           // make all vertices of the patch a corner
-          CGAL::Face_filtered_graph<TriangleMesh> ffg(tm, cc_id, face_cc_ids);
+          CGAL::Face_filtered_graph<TriangleMesh> ffg(tm, static_cast<PID>(cc_id), face_cc_ids);
           std::vector<vertex_descriptor> new_corners;
           for (vertex_descriptor v : vertices(ffg))
           {
diff --git a/Shape_detection/include/CGAL/Polygon_mesh_processing/region_growing.h b/Shape_detection/include/CGAL/Polygon_mesh_processing/region_growing.h
index 3029be2fe65..4aa40c42e38 100644
--- a/Shape_detection/include/CGAL/Polygon_mesh_processing/region_growing.h
+++ b/Shape_detection/include/CGAL/Polygon_mesh_processing/region_growing.h
@@ -33,14 +33,16 @@ namespace internal
   template <class GT, class Pair, class RegionMap>
   void fill_plane_or_vector_map(const std::vector<Pair>& normals, RegionMap region_map, typename GT::Vector_3)
   {
-    for (std::size_t i = 0 ; i<normals.size(); ++i)
+    typedef typename boost::property_traits<RegionMap>::key_type KT;
+    for (KT i = 0 ; i<static_cast<KT>(normals.size()); ++i)
       put(region_map, i, normals[i].first.orthogonal_vector());
   }
 
   template <class GT, class Pair, class RegionMap>
   void fill_plane_or_vector_map(const std::vector<Pair>& normals, RegionMap region_map, typename GT::Plane_3)
   {
-    for (std::size_t i = 0 ; i<normals.size(); ++i)
+    typedef typename boost::property_traits<RegionMap>::key_type KT;
+    for (KT i = 0; i < static_cast<KT>(normals.size()); ++i)
       put(region_map, i, normals[i].first);
   }
 
@@ -195,7 +197,7 @@ region_growing_of_planes_on_faces(const PolygonMesh& mesh,
         if (candidates.size() == 1)
         {
           Id new_id = *candidates.begin();
-          put(region_map, f0, new_id);
+          put(region_map, f0, static_cast<Id>(new_id));
           tmp[new_id].second.push_back(f0);
           tmp[i].second.clear();
         }
@@ -207,7 +209,7 @@ region_growing_of_planes_on_faces(const PolygonMesh& mesh,
     tmp.erase(last, tmp.end());
 
     //update region map
-    for (std::size_t i=0; i<tmp.size(); ++i)
+    for (Id i=0; i<static_cast<Id>(tmp.size()); ++i)
     {
       for (face_descriptor f : tmp[i].second)
         put(region_map, f, i);
diff --git a/Shape_detection/include/CGAL/Shape_detection/Region_growing/Region_growing.h b/Shape_detection/include/CGAL/Shape_detection/Region_growing/Region_growing.h
index f3b0268d190..20068827baa 100644
--- a/Shape_detection/include/CGAL/Shape_detection/Region_growing/Region_growing.h
+++ b/Shape_detection/include/CGAL/Shape_detection/Region_growing/Region_growing.h
@@ -451,9 +451,10 @@ namespace internal {
       Item_map item_map_ = Item_helper::get(item_map);
 
       m_nb_regions = 0;
+      typename boost::property_traits<Region_map>::value_type init_value(-1);
       for (auto it = input_range.begin(); it != input_range.end(); it++) {
         Item item = get(item_map_, it);
-        put(m_region_map, item, std::size_t(-1));
+        put(m_region_map, item, init_value);
       }
       // TODO if we want to allow subranges while NeighborQuery operates on the full range
       // (like for faces in a PolygonMesh) we should fill a non-visited map rather than a visited map
@@ -479,8 +480,9 @@ namespace internal {
     Boolean_property_map<VisitedMap> m_visited;
 
     void fill_region_map(std::size_t idx, const Region& region) {
+      typedef typename boost::property_traits<Region_map>::value_type Id;
       for (auto item : region) {
-        put(m_region_map, item, idx);
+        put(m_region_map, item, static_cast<Id>(idx));
       }
     }