I want to replace the flooring of this bathroom, USA, constructed 1984, off-grade with crawlspace. It once had a leak, and the plywood under it is very soft. The plywood over it now actually covers a hole where someone fell through. The leak is sealed now though.I wanted some advice on the easiest way to do this. I intend to pull up the tile, cut out the section of plywood (basically the whole room subfloor), then replace it. We're going to pull out the sink/cabinet, and probably intend to replace it since we'll very likely destroy it taking it out. We're amateurs, so is there anything we should consider? Anything of concern or any advice.
>>2994685what you are asking to do basically needs a near complete demolition of the bathroom, at least the removal of the vanity and toilet, but also the bathtub if you suspect issues with the subfloor under it as well. Once you've done that, you want to cut around the walls and remove the subfloor, there's many ways of doing that, some more efficient than others. Then just make sure you don't slip and fall through the ceiling below. Put blocking on the floor joists and then put exterior grade 3/4" plywood subfloor over it. Make sure to waterproof this time before tiling in some shape or form.
>>2994685Pull the toilet and remove the plywood cover.Start cutting back flooring to get a large enough opening to determine how much damage is done to the sub-floor and joists.You MAY be able to just remove the finish floor up to the vanity and tub and replace part of the sub-floor.I've removed vanities without destroying them many times.I've also jacked up the front edge of tubs to get fresh sub-floor up to six inches back when the joists and rest of the sub-floor were sound.TLDR: first step is determine the extent of the damage
can you provide a photo or photos from inside the hole? it can help get a better scope of the entirety of the issue. you can section off damaged areas and mount new subfloor. but you need a entry level of understanding to do so, and the first step is assesing the area that needs to be replaced, and thinking if it is easy to peice it in or remove the sheet. Subfloor runs into your framing, if you decide to or notice the damage goes to the framing, you can cut it at the plate, however you need to "sister" your joist so the new sheet can attach. Bathrooms carry a lot of weight in a small area, making a proper sister is probably not an option for you. There's a lot that goes into it. So if hav access to see the crawlspace take at look and post a photo. Or if not just detail what you saw.
a quick I have is with the plywood you placed to patch the hole, did it feel more solid? The bottom of your vanity is touching the floor on the left but growing as it goes to the right. Theres a lot of reason outside of subfloor for why that could be, however you said it was leak that erroded the wood. I ask because the plywood goes to wall. Can help out finding a solution. Because it can be more than just the subfloor. Yes interior framing maybe installed on top of existing, but maybe this bath was built when it was new. Regardless, the more info provided the better it is to give some direction on what to do
>>2994799There is no subfloor under the bathtub, it just sits on the joists. I intend to replace the toilet and vanity anyway, since the toilet isn't great and the vanity is very old and doesn't feel particularly structurally sound. I suspect it'd break if removed, so I'll just get a new one.The crawlspace is directly below it, its a short fall. It'd be pretty safe work I think.>>2994890Thank you.>>2994890I've decided to have it properly assessed before proceeding.>>2994903I don't understand what you're talking about, unfortunately. The plywood isn't a patch, it literally just sits on the hole to remove the falling hazard and prevent the cat from entering the crawlspace. It isn't "solid" at all, it's just sitting there. What is "growing"?
>>2994911All good. The plywood is a patch, meaning its a "bandage". As in its a temporary fix, to stop people falling. Solid meaning, how you feel walking on your floors that arent compromised, i.e. that dont sag or bounce. They are "solid", rigid. Growing is a short hand term that means the gap is increasing from one end.
I read your first comment in the reply, the tub sits on the framing. And that you want to remove the toilet and vanity. Given that, I strongly recommend removing everything and installing new subfloor. Having a tub resting on joist seems unreal. But I I guess that happens. Gl man
