Subfloor repair

[Addison]

Hi all!

Hoping to get a bit of advice. I have a second full bath that has a shower/tub combo. It
Isn’t used often whatsoever as my wife and I use the master bath.

We did allow a friend of our who was going through rough times to live with us for about 2 months and designated that as his shower and bathroom.

After he moved out, I noticed that valve body had a leak; the diverter valve was leaking. Getting into the crawl space and looking at the damage, there is some wood rot under the tub from the leak.

I know everyone will probably say pull the tub, replace the rot. This bathroom my wife and I remodeled (floor, vanity, lights, everything but the tub) without knowing the rot underneath. I would hate to have to rip out the tub, redo the shower to replace the floor.

I’ve been searching and trying to see if there is a way to repair the rot from within the crawl space. Do you guys have any suggestions? Not sure if butting up plywood to the rotted sections and bracing into place is a viable solution? What would you guys suggest?

 

[Cacher_Chick]

If the area is small and can be dried out well, you really only need to ensure that any point loads are being properly supported.
I see this problem quite often where the subfloor was not waterproofed and water pools around the tub skirt and seeps through the grout or areas that were poorly caulked. The area of flooring right inside patio doors shares the same issue. #realworldproblems

 

[Sponsor]

 

[Addison]

Makes complete sense. The tops of the joists are fine and don’t show signs of water damage. I think to ensure proper support across the load it might be best to put plywood under the rotted areas and support it to the joists as added security. Do you see any issues in doing this?

We are also planning on selling the home, as it’s not our forever home, and I do not want an inspector to make this an issue.

 

[Addison]

Anyone other input out there?

 

[Reach4]

Anyone other input out there?

See https://www.rotdoctor.com/epoxy/epoxyguide.html
I have not tried the product. It is sold to strengthen partially-rotted wood.

 

[Cacher_Chick]

Makes complete sense. The tops of the joists are fine and don’t show signs of water damage. I think to ensure proper support across the load it might be best to put plywood under the rotted areas and support it to the joists as added security. Do you see any issues in doing this?

We are also planning on selling the home, as it’s not our forever home, and I do not want an inspector to make this an issue.

The trick will be to do it with good workmanship so that it blends in instead if sticking out like a sore thumb.

 

[duomit]

How have you done it with epoxy? Went out good?

 

[Addison]

this is the idea i had. I was going to ensure that the wood was dried and than use a wood hardener on it.
I was than go to take a piece of 1/2" plywood and secure it up tight again the rotted floor and secure the plywood with pieces of 2x4 attached to the floor joists.

Anyone else have any recommendations or see this as a good idea?

 

[Cacher_Chick]

Anywhere wood touches wood needs to be glued and screwed to help prevent future squeeks.

 

[Addison]

Ah ok! Any particular glue/ adhesive you would recommend?

Aside from that, Is does rest of the idea suffice?

 

[Jadnashua]

If you're going to glue/laminate the wood together, except say on the top of a joist, do not use construction adhesive. You want a full spread of wood glue like Titebond II. Construction adhesive will work on the top of a joist because first the surface area is small, and you can apply a bunch of concentrated pressure from the fasteners. When trying to do the same with a large flat sheet, the pressure per square inch is way lower, and you'll not get a full spread. The voids left can be problematic. Wood glue (you can spread it with a tile trowel, or a putty knife) is more fluid and will spread easier. You still need to clamp things, and that's where the fasteners come in...they act like glue clamps and, pretty much aren't needed after the glue dries, but would be a major pain to remove later. In either case, you need to work fairly fast or the adhesive skins over, potentially compromising your joint.

 

[Addison]

Thanks very much! Makes perfect sense! I figure with Titebond, some wood screws, and the side 2x4's as supports, it should set and stay in place well.

Ill likely tackle either this weekend or next! Thanks again for all the help, support, and knowledge from everyone!

 

[Addison]

Hi All,

Its been a little while since i was able to look into this again; had a few things come up that required immediate attention. I took a few photos of the above damage from the water; i went and inspected underneath the area from the crawl, and all the subfloor is solid with no issues. The only soft spot was directly around the water line; otherwise its just a nasty appearance more than anything. i attached a few photos and would love some opinions on if i should even do anything to it and if so what the recommendations would be. thanks in advance!

 

[duomit]

I would replace the spot around the water line.

 

[Addison]

appreciate the suggestion @duomit!

What would the proper way be to replace that actual area? I assume you are referring to just the 2x4 that the water lines come up through and not the subfloor where the overflow goes down?