Wood – Help with moldy deck from bad boiled linseed oil job

deckfungusmoldwood

I need some opinions on what to do about my deck. About about a month and a half ago we applied linseed oil to our deck. Our first mistake was that the deck had a sealant, so the oil didn't really penetrate. The second mistake is that we didn't use an anti-fungal.

After some heavy rain we started to see mold spots on the deck. Really bad in some of the ruts where water collects.

I'm hoping that since the linseed oil didn't really penetrate that the mold is mostly just on the surface. I don't know how realistic that is.

I initially tried treating with concrobium, but it didn't really help. I am thinking that was because it could not penetrate the wood.

After that failed attempt, I cleaned the mold off with white vinegar. This worked great. All the mold just dissolved off. It hasn't rained again since I cleaned with vinegar, so I don't know how effective it was yet.

After cleaning with vinegar it has exposed the wood that was underneath the mold spots. I need to figure out what to do about this since I don't want moisture trapped in the wood, making it worse.

I've included some pictures of the deck and some mold spots. https://imgur.com/a/KsdA8JR

My question is: Should I just completely strip the deck and repaint? Or can I wait it out until next summer? I was considering sealing up the exposed wood from cleaning. One of the main places I'm concerned about mold is at the legs of the deck because they are in the dirt, so they are constantly getting moldy again from the moisture.

Best Answer

So your posts are in direct contact with the ground? Not pressure treated? Maybe redwood or cedar? You might just wait until its warm enough to deal with. Best bet may be to pressure wash and strip the deck then sand and reseal or stain or whatever your preferred covering is. If you can keep the deck dry and warm for a sealing project now, you could do it now. They make a deck wash that will clean your deck, very similar to a bleach solution. You need to kill the mold before you apply another treatment. If mold on the posts is an issue, you need to look into a different post, either pier blocks or replacing the posts with pressure treated wood.