[Julka7]

We are fixing up an old house with an enormous (probably around 800 sq ft) deck.. About 2 months ago we've replaced a number of joists and parts of deck boards because they had some sort of rot on them. With some of the joists, we got out the rotten parts, filled with wood putty and put deck flashing tape over them. We've also recently cut some gaps between the boards because they were too close together and would close up completed when wet. It's been a very wet spring/summer (we are in NYS) and we've only had a chance to stain a small portion of the deck. Yesterday we looked under it and looks like the rot has spread to another handful of boards next to where the rotten boards were removed. It is present in about three different places included the part that we stained.

The deck is from 8-15ft off the ground. The ground is covered is a bunch of old boards.. and yesterday we also discovered that one of the gutters is not being redirected so that is probably not helping. There is no standing water, but the ground stays moist.

The boards that are rotten are a bit darker with white spots.
Attaching a picture.
Is there a way to tell what kind of rot it is? What to do about this?

Thank you for any suggestions!!

 

[Nealtw]

try that again.
Your search - "https://imgur.com/a/YOqV5Tv" - did not match any documents.

 

[Julka7]

It didn't let me add URLs, but just let me add an attachment (added it to the original message).

 

[Nealtw]

Looks like mold.

https://www.doityourself.com/stry/5-tips-for-cleaning-mold-off-of-treated-lumber#:~:text=Go%20with%20something%20very%20simple,ratio%20of%202%20to%201.

 

[Julka7]

Parts of the boards that we took out were mush. Can mold destroy them to that extent?

 

[Nealtw]

Parts of the boards that we took out were mush. Can mold destroy them to that extent?

Yes it can there are different types of mold and different kinds of rot, none of which do the wood any good.

You can check the quality of the wood with a sharp screw driver or an awl which would point out soft spots.

After cleaning it you can buy the copper treatment that is in the lumber and paint it on. It's messy like painting with green water but that would keep the mold down.

 

[Julka7]

Awesome -- thank you!!
Painting with green water is way better than ripping out deck boards, which we were assuming we would have to do.
How far away from the affected boards do you think we need to go with copper treatment? It seems this stuff is pretty contageous given those boards looked fine two months ago.

 

[Nealtw]

Awesome -- thank you!!
Painting with green water is way better than ripping out deck boards, which we were assuming we would have to do.
How far away from the affected boards do you think we need to go with copper treatment? It seems this stuff is pretty contageous given those boards looked fine two months ago.

I would do the drop cloths and protect the wall and go for it and do the whole under side.

 

[Mike Milam]

My deck boards (5/4 X 6 PT) I put down when I built it 10 years ago, rotted from the bottom up. I started to just replace the ones that were obvious. Then I thought better of it and replaced all the deck boards. The way I saw it was I would be replacing a few every year and when stained, they would stand out like a sore thumb. My deck is about 850 square feet. I have better pictures, but not handy.

 

[carpdad]

About that copper treatment, not a same brand but couple of pointers. I think it settles so must be shaken up frequently. It also has a strong smell and won't be washed off from hands easily. Wear a glove and spray with a garden sprayer instead of brushing. Probably eye protection as well.


It is meant to treat the lumber endgrains where the solution can wick into the fibers. Not sure how much protection it will give on the lumber surface for the cost of the solution.


Wood filler is not good. It may look good but it may (more likely) trap water and make it worse.