View Full Version : Moving toilet drain across joists

10-24-2007, 06:23 PM
I am in a remodeling project at home and have to move the toilet to the other side of the wall that the vent stack/ drain are in. I have to cross two joist to get to the new location, and would like to know how to reinforce them so as to not weeken there ability to suport the floor once the holes are made.

I was thinking of anchoring predrilled angle iron as a bridge above the new pipe to restore its integrity, but would like someones opinion about this before I take a saw to the joists.

If there are any other means of doing this, please let me know.

10-24-2007, 09:31 PM
What size joists?

What size pipe?

A piece of angle iron across the top won't do it: you need to reinforce above and below (the top's in compression, the bottom's in tension, and both are completely necessary.

Maybe a set of them, above and below... depends on the size of pipe vs size of joist. Personally, I'd want an engineer to spec that sort of solution. A few hundred bucks, but I sleep better at night.

Other, more straightforward options:

- make the new connection lower, so that the pipe runs under the joists. Depends on what's downstairs.

- reframe that section of the floor, the way you would for a staircase or skylight opening, with a doubled header at each end.

- my favourite: change the design, so as to avoid the problem in the first place.