my Dad's shed had a roof that he didn't take care of for a while and now appears to have rotted in several regions.

I'll provide several pictures, but the video is best: Link

What is the best way to approach a problem like this, and what would be the best solution to it. Also, what is the likely extent of the damage so far, and is this a risk to the roof failing?

Left Side: Left Side

Right Side:

enter image description here

1 Answer 1


The black is bad get a screwdriver and see if the plywood is compromised. Push on the screwdriver and if it goes into the wood 1/8 “ or further the wood needs to be replaced. If it is still solid I would use a very strong solution of hydrogen peroxide and water 5-8% and saturate all the fungus areas a second treatment may be needed but this will kill the surface fungus that will break down the plywood.

Note 8% hydrogen peroxide will bleach just about anything including your hair so use ppe. It can be applied with a paint roller or sponge, at this strength I would not spray it as I do with 3-4%.

AAA. Always add acid to water to reduce the exothermic reaction when diluting concentrated hydrogen peroxide with water.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.