We are redoing a wet room on the ground floor and we have uncovered the floor boards.

I'm looking at this and I'm totally baffled.... the joist doesn't even reach the end of the room... what's supporting it is a mystery to me...

What's the best way to fix this?

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Example of the far left joist as well below - this one looks a bit rotten and has a much better joist connected to it that runs to the other end of the bathroom I believe.

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  • You're correct - there is nothing supporting that end of the joist. There MAY be a beam under the joists just under the floor (see how some of the joists are overlapped right where the floor ends?). If that's the case then the cut joist may just be a couple of feet cantilever. – SteveSh Nov 29 '20 at 0:45
  • Note that what you have there is not uncommon. The framers put down the floor joists and call for the framing inspection. It passes, then the plumbers come in to rough-in the plumbing, at which time they sometime cut holes, cut stubs/joists, and just hack up the framing in order to make the plumbing work. – SteveSh Nov 29 '20 at 0:47

Aah, plumbers.

Google instructions on 'framing an attic hatch'. At a minimum, you want the cut joist to T into something across the two good joists.

You also want to put short joists (going in the same direction as the rest of the joists) as close to the plumbing as practical to support the edge of the flooring.

If you already have a compressor available, a palm nailer will drive the joist hanger nails in tight spaces quite nicely.

Edit---- Here's a bit of a diagram to show how the new parts should go. It's probably best to assemble them with joist hangers (ie, Simpson LU28, if the joist is a 2x8). You'll have to notch a little for the plumbing on the right. (These notches are perhaps the worst type of notches you can put into a floor joist, so make them as small as possible.)

If the joist on the left is rotten all the way along, I'd sister an additional joist through as much of the length as you can manage. (Glue and screw.) If it's just the very end, you could extend the perpendicular joist to the next good joist, but in that case, double the perpendicular. enter image description here

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    don't blame the plumber it's the framer who didn't make allowance for the pipe, the guy needs to learn how to read plans. – Jasen Nov 29 '20 at 10:32
  • Thanks guys - not sure I can quite visualise what you mean Aloysius... Also, the far left joist seems to only be 3 feet, looks a bit rotten, and when looking under the floor, looks to be attached to a good joist that goes to the other end of the bathroom. That rotten one moves a bit so probably not best to attach the cut one to it? – Suzan Nov 29 '20 at 12:04
  • Hey Aloysius, couldn’t access my account properly. I was going to say, so do we have to take out brick where the new noggins are going in? Cos I’m thinking you’re saying to notch the noggins so they can go into the wall like the other joists but we’d need to remove a bit of brick for them to go under the wall no? – Suzan Aydın Nov 30 '20 at 2:42
  • On my phone at the moment, so can’t really see the detail at the wall. That said, your new mini joists should bear on something solid for a minimum of 3 inches. If that means pulling out bricks, then unfortunately that might be the way you have to go. Alternately, you might be able to sneak another perpendicular section close to the wall and connect into that. – Aloysius Defenestrate Nov 30 '20 at 20:35

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