Many thanks. I built a new wad, and now have no problem.
Not sure why I had the issue, before.

While I am on this..... I notice that your textures are not powers of 2.
They are multiples of powers of 2, though.
Does a texture of 512 X 384 work OK with most graphic cards?
I thought it was best to use something like 512 X 256 or the like.
If anyone has the difinitive word on this, I would be interested.

Anyway, the house geometry is great, and since that is the main point, congratualations on a job well done.
Regards,