Garage Roof Mould

[Sonic70]

Hi All,

Had a new roof put on our garage last May, mineral felt over plywood. Noticed after we had that really cold spell and fog that areas of the ply had mould on it. There is some ventilation in the garage as there is about a 1 inch gap over the garage door and a side door with a gap at the top. My thoughts are the foggy air blew in the garage and froze to the ply causing the mould. I was thinking of coating the ply in an oil based shed/ fence treatment I have. Any other advice appreciated.

 

[Sonic70]

 

[Sonic70]

It's barrettine wood protective treatment.

 

[noseall]

View attachment 369895

It's common to see BSM on the underside uninsulated roofs.

 

[Sonic70]

Thanks, would applying the wood treatment make any difference? Or is there something else I can do?

 

[robinbanks]

Insulate it? Are you going to be working in the garage when it's cold outside?

 

[Sonic70]

When I do work in there I always have the side door open to let fresh air in. What insulation do you recommend?

 

[robinbanks]

I was more thinking that an insulated garage would be more pleasant to work in with the doors closed and a heater on!

I'd used seconds grade king span for a garage; doesn't need to be pretty, probably 100mm cut edges on a table saw with a slight taper, so it's a trapezium shape, few mm over exact width on the long edge of the trapezium, wedged in and the taper filled with expanding foam