No one?

My guess: Buildings are not treated as a part of terrain so you have to put the elevation (in this case) 2.
/upvoted

I spawn them out side of the house and then tell them to get in and thats whats happend.

Setting the waypoint elevation to something, perhaps?

no. I don't touch the elevation.

Did you try setting it to something? If not, try.

Units on waypoints walk through the floor on some buildings.

AI in your group will walk up the steps in some buildings and not others.

Control tower.
AI on waypoints will walk up the steps but will first walk through the steps and walls.

AI in your group won't walk up the steps in the control tower when given a
position to move to.

No addons no script, height is not an option with building locations.

It's all completely messed up.

Had this myself.

I fixed it by having the AI move into position from the outside.

Well, i've seen them fall through terrain as well, and concrete areas on the airport so yeah upvoted.

Mass closing ancient tickets with no activity for > 12 months; assume fixed or too trivial.

If this issue is still relevant in current dev build, please re-post.