Cutout of joist for toilet drain

Does this look kosher? The joist is about 2" thick and 7" wide. It looks like the cutout is more than 1/3 of the width of the beam. One joist is supported with some extra lumber, but it still doesn’t look that great.



Structural defects in both pictures. Greater than 1/3 the joist depth, as well as closer than 2 inches to the edge…

also cracked .

So, what’s the remedy? Would sandwiching it in OSB do the trick? How far on both sides?

This is one of those things that Home Inspecters like to comment " refer to a licenced contractor or structural engineer"

Having said that, OSB sandwidch would make it stronger, but would NOT fix the problem, the joists are almost cut in half.

ceiling joists/overlays are mainly outward pressure support. hard to say from a picture but I would say that an upright from the joist up to the rafter would do the trick.
if that were a floor joist there would be a problem.

Thought it was a floor joist

Bob, sure looks like a floor to me.

I am seeing a new framed wall and some subflooring and two different size pipes.

I don’t think we are seeing the whole picture from those two pics.

The title calls it a toilet drain, so must be an attic being finsished as a bathroom, so now the ceiling joist are floor joist.

The span of those might be sized wrong for this new load also.

More information is required.

Marcel :slight_smile: :smiley:

Yes, it’s a (now) a floor joist. It was a ceiling joist, but we’re refinishing an attic and putting in a bathroom.

The joists are around 22" on center, if I recall correctly. They are a full 2" thick, and 7" wide. The span is around 12’ or so. I talked about the joists with a structural engineer, and he didn’t seem to have any problem (before the cutout - of course).

It’s not acceptable the way it is and needs reinforcement with a product like THIS

Here is a animation Choose the hole reinforcer

Photo Gallery

You ever see this product of Mikes being used?


The problem here is renovations being made with attic framing now becoming a floor, where as before was just holding up the ceiling. This is a job for a licensed Architect.

The previous post is indicating a bathroom floor framed with 2x7" framing at 22" o.c. for a span of 12’-0".

This type of framing is inadequate for the span at 12’.

Those members are to small to get the loading required for a floor. 30# live load, 10# dead loading.

If the riser from below had been located as such that the branch soil piping would run parallel to the framing, these holes would be unnecessary, but the framing is still inadequate for this attic framing to become a floor.

Recommend engineering by a qualified Architect required, for redisign and alterations.

:slight_smile: :smiley:

Marcel , didn’t he mean 2x8.

Also besides that issue I have seen them rais ethe toilet on to a platform.

This way the pipe can be above the joists.

Hi. Bob,

I believe this is an unsurfaced lumber framing.

The joists are around 22" on center, if I recall correctly. They are a full 2" thick, and 7" wide. The span is around 12’ or so. I talked about the joists with a structural engineer, and he didn’t seem to have any problem (before the cutout - of course).

And I am assumming he meant 24" centers.

If we are looking at new framing in the pic to be a knee wall, plateform for toilet might open a headroom problem,

Like I said before, too much information missing.

Recommend design by an Architect.

This apprears to be a 1930 built structure by the remnants of knob and tube. So god knows what the framing is like in that place.

Marcel :slight_smile: :smiley:

Oh you caught that porclein knob too.:slight_smile:

Here are some pictures of the beef up.






That doesn’t look “engineered” to me. It looks like a patch. Was that designed by an engineer, or architect?

I’m finding it a little hard to believe that that little bit of plywood is going to make a huge difference. Those metal plates appear to be simply shields to keep from nailing into the pipes, and not structural.

Agreed. The plywood should at least be continous under the pipe, where the wood of the joist is thin and in tension, prone to snapping. Next time, cut more pipe and less wood. :stuck_out_tongue:
Run the pipe parallel to the joists over to a supporting wall, then drill if you must.

John Kogel

From what I see, through the eyes of an architect, those joists will fail, and the “beef-up” isn’t nearly beefy enough. The joists will still fail. Isn’t this the same guy who wanted to “hinge” his roof, earlier? And didn’t we advise him **then, **several of us, that he needed professional advice? This is one reason why that was true. Whatever he saved in professional fees then, he will now spend the same amount or more trying to correct this atrocity. If the plumbing must be perpendicular tio the joists, it must be run either over or under them. The joists cannot be weakened by such huge holes. They will fail, perhaps catastrohically. There is no “beef-up” that will prevent the failure.

Whoever suggested a post to the rafters ought not give structural advice. What on earth will that solve?

FYI, I hired a structural engineer to design the framing for the dormer.

This work is being done by a general contractor, and I’m just checking on his work to make sure it’s sound.