# Wall Layer Reference getting Core layer when Int or Ext selected **URL:** \ **Category:** Revit\ **Tags:** dynamo\ **Created:** [November 12, 2021, 11:37am UTC](https://forum.dynamobim.com/t/wall-layer-reference-getting-core-layer-when-int-or-ext-selected/70309 "2021-11-12T11:37:08Z")\ **Posts on this page:** 1\ **Showing post:** 2
**Author:** ![honeyjain619](https://sea2.discourse-cdn.com/flex022/user_avatar/forum.dynamobim.com/honeyjain619/32/121215_2.png) [@honeyjain619](https://forum.dynamobim.com/u/honeyjain619)\ **Post date:** [November 12, 2021, 12:00pm UTC](https://forum.dynamobim.com/t/wall-layer-reference-getting-core-layer-when-int-or-ext-selected/70309/2 "2021-11-12T12:00:49Z")
Hello @Epyns1 , you can refer the previous topic similar to your topic > [@Dimension walls](https://forum.dynamobim.com/t/dimension-walls/47616/2): > > Hi @selim.celem, You can simplify your graph with the Wall Edges References node. [Dimension walls and openings.dyn](https://forum.dynamobim.com/uploads/short-url/iUA2z44hOBW5MCrAf5Ov4XJPAYQ.dyn) (17.5 KB) > [@Wall dimensions without opening](https://forum.dynamobim.com/t/wall-dimensions-without-opening/59996/4): > > Hi @robert12546358, You can easily remove the unnecessary edges/references like this : > [@Automatic Dimension Walls](https://forum.dynamobim.com/t/automatic-dimension-walls/6970/5): > > To be able to dimension openings in walls you have to do some filtering. First you need to take the vertical faces of the wall which you can do with Surface.FilterByOrientation from Clockworks package: Then you need the faces that are perpendicular to the dimension line. You can filter them like that(this is the principle for the filtering inside Surface.FilterByOrientation too): Then you need the references of the actual wall faces. I did this with this little node I foun… --- _[View the full topic](https://forum.dynamobim.com/t/wall-layer-reference-getting-core-layer-when-int-or-ext-selected/70309)._