Mold on pressure treated floor joists?
Greenhills
| Posted in General Questions on
Hey all – I had a shed delivered to my property that I’m turning into a house. It has pressure treated 2x8s for floor joists, on piers about 1.5-3ft off the ground.
I’m getting ready to put mineral wool and then polyiso boards to insulate the floor, but noticed many of the joists have block spots that look like mold? The moisture reader reads between 10-14% on the joists. Is this a problem to insulate with or how should I approach? It’s been outside for about three months with varying humidity, etc. Thank you!
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Replies
The mold is probably just growing on some surface debris stuck to the joists. You can probably clean that off with a brush and be fine if it's concerning you, just be sure to wear a respirator while doing that. You can get mold killing primer too if you want to ensure no further mold growth, but I don't think it's necassary here.
Bill
Greenhills,
A single bottle of Concrobium will cover all of that.
Thank you Bill and Malcolm, it seemed like it was coming off pretty easily with some vinegar and wiping so thinking it's not too far deep down, but wiping all the joists was a daunting task for the entire floor system, so I did just spray a bottle of Concrobium and hope that does the trick. Thank you!
I doubt the mold is really into the wood to any significant amount. There are various metal salts essentially soaked into the wood during the treatment process that should prevent mold growth within the wood.
Bill