I think it is because I have a cavity that has exactly the same strength as the concrete slab BM.
If I make the slab BM stronger it of course runs through.
If I make it weaker then the cavity runs through and the slab stop inside the cavity.
It is only when they are exactly the same strength and at the edge of the slab that the slab cuts the cavity but then thinks it has to stop.
As soon as the slab extends past the side of the wall the slab cuts everything.
I understand that when 2 BMs have the same strength then Archicad will decide which cuts the other.
Clearly here the slab is cutting the cavity of both walls but why is it not cutting the face brick skin which is weaker.
Just a glitch that I can live with as I would never model the slab to the edge of the wall because that is not how it is built so the floor plan display would be incorrect even if the section was.
Probably it is a deliberate decision by GS because there may be an external render skin or cladding (siding?) on the outside of the wall that has a much weaker strength.
Because the slab does not pass all the way through the wall but meets with a skin (cavity) that is stronger then it will stop the slab on the side of that skin that the slab is on and the weaker skins on the outside of the wall will continue.
But when the strengths are equal and the slab is clearly cutting the cavity then my logic says it should continue cutting the other skins as well if they are weaker.
So in my opinion a glitch.
Barry.
One of the forum moderators.
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