Metal roof over asphalt roof?

[basstracker89]

Yep, got to weigh the options

 

[Cruisers460]

and the screws I hear only last 10-12 year

The washers dry out from sun exposure and need replacing. There is a different screw available now that covers the washer in steel, supposed to last much longer. I asked my roofer to use them, he said it would add a couple of hundred to the price and I told him it was cheap insurance.

 

[dcline9163]

I have some friends in Blairsville that has a metal roof on their cabin and after a while they started getting leaks in the cabin, long story short, over time the screws will back out and creates a leak, tin gets loose and water can get under the tin and hit the backed out screw holes.

 

[GAgunLAWbooklet]

I've got an 8 year old metal roof on top of 1.5" inch thick foam board insulation, which is above a 20-year old asphalt shingle roof.

8 years later, everything seems good.
No problems, and the rain does not seem excessively loud.

 

[joel2000]

I have some friends in Blairsville that has a metal roof on their cabin and after a while they started getting leaks in the cabin, long story short, over time the screws will back out and creates a leak, tin gets loose and water can get under the tin and hit the backed out screw holes.

That’s exactly what I don’t like about a screw down roof. Expansion and contraction makes screws back out and the sun loves those little neoprene washers. If you’re gonna go metal do standing seam. All fasteners hidden and no chance for leaks around them. More expensive but pretty well lifetime roof. Like others have said…. Colors will bleach and change. Kynar finish is the best but overtime even it changes.