Rotten board repair

[Wish-I-Were-Fishn]

I found a rotted area on my deck. I tore the steps off, dug out the rot and put a fan on the area to dry it out. Once dry I soaked the area good with rot stop (Minwax).

I was planning on filling the area with wood putty, or Bondo, but can I just squirt some water proof foam in there? It's hard to get anything under the area where the stair tread connects to the raiser.

[MSRiverdog]

Not much to work with there but if you have it really clean of rot Bondo does a great job. Just make sure you sand it down before it's totally set. I've repaired windows that way and it works wonders.

[delcecchi]

Sort of hard to see what the board is. Is it load bearing? Would it be possible to replace the board without major deck surgery?

[Surface Tension]

Its a trim board, inside of it is your rim joist.

The tread was against the trim or debris selected there. It ended up being was wet longer then it was dry.

Is that cedar?

[delcecchi]

Since it is just trim, I guess either filler or a new board would work. Advantage of new board is it could be green treated.

[Wish-I-Were-Fishn]

Its a trim board, inside of it is your rim joist.

The tread was against the trim or debris selected there. It ended up being was wet longer then it was dry.

Is that cedar?

Yes, it's cedar. The top step was wedged tight up against it and water would collect in that corner. I guess dirt and debris sealed it up tight enough to hold the moisture.

[Wish-I-Were-Fishn]

Plus it is on the east side of house out of the sun.

[CAMAN]

I wouldn't worry much about it seeing as it's just a trim board and once you place the stair tread back it will be covered up. I would clean it well getting as much loose stuff out of there, let it dry well, seal it well with a couple coats of whatever you are using on the rest of the deck and replace the tread being sure to leave a gap to allow for drainage. And in the future whenever you're refinishing the deck be sure you coat that area thoroughly to keep it sealed.

If you try and replace the entire board you will need to remove the stairway and that could open up a whole can of worms. Placing a Bondo type patch could possibly create a water trap that may hold water and cause even more problems.

[Wish-I-Were-Fishn]

I like that idea because it is not visible.