Repair Water-damaged Subfloor

[mmawhorr]

The floor near my back door has sustained water damage. It is soft in about a 2-foot length to about 8" from the wall. I know the flooring will need to be replaced, and I'm also certain the subfloor will as well. Best I can tell the joists are not significantly damaged, but I'll know for certain when I open it up.

My question is, how do I replace the subfloor as it goes under the wall? I'm sure it extends under the sole plate. Is this a job I can accomplish myself? I have a fair aptitude for home repairs.

Thanks in advance.

[David]

I'm surprised you haven't heard back from anyone. I can't tell you if you can do the subfloor or not as I don't know how to deal with it. Do you know which way the joists run as compared to the exterior wall you mention? Do you know the source of this water damage? What type of exterior sheathing/siding do you have?

[Cole]

2 suggestions:

Take a reciprocating saw and try to cut the nails.

You can cut the studs in the wall and header across them and simply just tear out the floor and replace studs in the section you put the header in. You may have to remove drywall, exterior siding etc...

Either way there is no one easy fix, just be careful with the second option if the wall is load bearing.

You may not have to replace the subfloor under the framing. Most people will not replace it under the framing unless it is a big section.

[mmawhorr]

Thanks for the responses, guys.

To answer your questions, the floor joists are perpendicular to the wall. The wall itself is 2x6 with sheetrock on the inside, OSB & vinyl siding on the outside. The wall faces south, and the previous owner had a storm door with full-length window over the door. The summer heat built up inside and warped the steel door. It also deteriorated the brickmold around the door. The caulking around the door was badly deteriorated, and it appears storms from the south just blew against the wall and the water came in around it. We don't use the door much, and I didn't notice the problem until it was too late.

The house is a 2-story, and the floor joists on both floors run perpendicular to this wall, so it is load-bearing. Will codes generally allow me to replace the subfloor up to the wall and scab in 2x10s alongside the rim joist between the floor joists to support it?

[VALENT]

I would not try to replace the subfloor under the wall framing unless it was absolutely necessary. It will be a very difficult job even if pretty much everything goes well. I dont know anything about the codes question. I do think you have a pretty good idea of what needs to be done. Pretty much, you are going to have to open up the floor and find the extent of the damage and work from there.

[Cole]

Why are codes involved for such a little job anyway?

[CThomp]

I don't think anything with codes or inspectors or anything like that needs involved when all you're doing is repairing you house.

[Cole]

I don't think anything with codes or inspectors or anything like that needs involved when all you're doing is repairing you house.

Trust me you are not alone, you would be surprised.

[David]

The house is a 2-story, and the floor joists on both floors run perpendicular to this wall, so it is load-bearing. Will codes generally allow me to replace the subfloor up to the wall and scab in 2x10s alongside the rim joist between the floor joists to support it?

I don't see how sistered joists will help support your wall. No matter how well you support it, you still have rotted subfloor between joists and wall. (which could lead to further rot or mold)

I began to suggest methods on cutting out the rotted subfloor. But then I began to wonder how well your sill plate resisted rot. It should be PT, but I wonder how well even PT withstands rot/mold under your conditions. Open up your wall and get back to us.

When you open up your wall, you may discover mold. Many people have been exposed to mold and not had problems. But the fact that some people (whether few or far-between) get sick from it would make me want to take precaution not to get it in my lungs and especially not into my hvac system. Be prepared to kill the mold. And if you have kids, be sure they're not around.

[Cole]

Dave,
That is an excellent point that I forgot to mention, If you see something that is mold but are not sure, please call a mold remediator to give you an inspection.

Be careful of mold, it can be very very dangerous.