Metal roofing

[FarmerWill]

Just a fast question.
Working on a garage/shop/shed built in the 20's by my family.
Need to re-roof a section of the building and I truly did not want to disturb anything below the metal.
Can I put the new sheets of galvanized over the old?

 

[Hot Rod Grampa]

I would not do it on my roof. The metal will sweat and the moisture needs a place to go. I would be afraid the roof would rust through where the sheets touch each other.

 

[readhead]

Not a good idea. Condensation will get trapped between the sheets.

 

[FarmerWill]

Thanks fellas. Wondered about that, especially down here on the coast.

 

[bob15]

I used 1x3 furn strips between the asphalt old roof and the new metal roof.

 

[James-W]

I wouldn't put 2 layers of regular shingles on my roof and while I know very little about metal roofing, I wouldn't want 2 layers of that type roofing up there either. I suspect you would be "asking" for trouble if you were to do it.

 

[kbs2244]

Not to mention the weight.

 

[brownbagg]

its a shed, hell yes in a heatbeat.

 

[77Birdman]

Kinda agree with brownbag. Would never do it for a customer for obvious reasons, however if its a small area on a shed or small garage, the worst that's going to happen is a shorter life of the finished product. If you really want to get fancy, put down a vapor barrier of synthetic felt paper, install perpendicular 1x3's for nailers and your fine. That is an acceptable way to put metal over existing asphalt shingles. Should work on metal ok too.

 

[readhead]

You have to take the screws out to put another sheet on top. At that point why wouldn't you remove the old sheet?