Describe the two parts of a 'T' shaped intersection

I have architectural drawings that contains numerous instances of intersecting walls that form a 'T' shape. To state the obvious, a capital 'T' has two parts:

1. the top line
2. a vertical line that buts up against the T's top

What might each of these two connected walls or segments be called?

I am asking for word suggestions. The words may or may not be math-based. Short words (short number of characters) that most people understand are preferred over obscure words that few people understand.

Edit: I'm currently using 'T-Top' for one. That's okay I guess, but I couldn't think of anything short for the vertical piece.

Solution 1:

If you like your 'T-Top' you could use 'T-Shaft' or 'T-Leg'.

Shaft or column and capital or cap or lintel would describe the joint in terms of the T and keep it in the architectural domain—but it might create confusion with vertical elements.

If the wall which constitutes the horizontal of the T is the primary load-bearer, you might write of a main and an intersecting or butted or abutting wall—or a mainwall and a buttwall.

If the wall which constitutes the vertical of the T is primary, you might write of a main(wall) and a crosswall or crossing wall.

Or it might be best to consult an architect for appropriate terms of art.