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Citi
Basement stair stringers rotted in the concrete floor
Citi

The bottom portion of the wood stringers of my basement stairs have rotted. The concrete flooring must of been poured in around them, so now I have two rectangle shaped holes a few inches deep mostly filled with rotted wood. Additionally, when there is heavy rain the water pools in these holes. It seems as if the water is coming from the ground up.

Would it be ok, after removing the rotted wood, to plug the holes with new concrete? (And then replace the stairs)

Thanks for any advice.

dj1
Re: Basement stair stringers rotted in the concrete floor
dj1

Quote: "It seems as if the water is coming from the ground up. "

If this is true, then whoever built the staircase really screwed up.

Clean the holes and get all wood left overs out. Then fill the holes with new Hydraulic Cement (available at the stores - Drylock or Qiukrete brands) and make sure the place is sealed.

When you install new stringers, make sure to use PT wood in contact with the concrete. Also make sure the stingers are anchored and secured to the concrete. There are various methods of doing that, you will have to study your options and pick the one which is the right one for you (youtube is a fair source of info).

Mastercarpentry
Re: Basement stair stringers rotted in the concrete floor
Mastercarpentry

Something I've taken to doing with stringer plates resting on concrete is to use plastic shimming at the points where I fasten the plate down so that it no longer touches the concrete. A few layers vinyl siding works well for this but you have to fasten well because you lose the 'grip' that friction between plate and concrete used to provide. Strips only, doing the whole area will trap water which is what you're trying to avoid. Now the wood can fully dry and won't 'draw' moisture from the concrete.

Back in the days of below-ground CCA treated lumber being available, direct attachment wasn't an issue but with today's ACQ etc I have not found it nearly as durable- it simply doesn't hold up as well against moisture as the old treated wood did. I redo some decking on a small porch which is constantly shaded and wet every couple years and the framing under it about every other time around. It sits on a slab so there's not much I can do to aid drainage. After shimming up with vinyl I no longer have to re-do the whole thing every time like I used to. The owner doesn't want anything but wood- no composites- so he bears the burden of having what he wants. It's about time to hear that I've got a couple hours work there again :rolleyes:

Phil

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