Metal roof over shingles roof.

[hawkeye08]

Ice and water shield rolled on the roof over the shingles first, then the metal roofing.. I only do out buildings with screw down metal, my house is standing seam, it's the only way to go on a house IMO..

I want to do standing seam on my roof (25yr old with shingles currently), but have not figured out the plumbing vents. This is existing house, what happens if vent pipe is at seam? How are those sealed? I don't want to end up with leaks around the plumbing vents (also have one bathroom vent out roof).

 

[clemsonfor]

Air passes between the 5 major ribs and the 1x4s as well as the 8 minor ribs.

View attachment 615945

I am not sure why I didn't even think of that??

 

[4570Man]

I want to do standing seam on my roof (25yr old with shingles currently), but have not figured out the plumbing vents. This is existing house, what happens if vent pipe is at seam? How are those sealed? I don't want to end up with leaks around the plumbing vents (also have one bathroom vent out roof).

Take the vents out and re install them later. It wouldn’t make any difference if it has to run horizontal for a little ways to come up where you want.

 

[/pine]

Take the vents out and re install them later. It wouldn稚 make any difference if it has to run horizontal for a little ways to come up where you want.

:thumbsup: A lot of designers and architects specify that all stacks and vents etc. be offset to the back of the roof as to not show from the street...

 

[atsah]

I want to do standing seam on my roof (25yr old with shingles currently), but have not figured out the plumbing vents. This is existing house, what happens if vent pipe is at seam? How are those sealed? I don't want to end up with leaks around the plumbing vents (also have one bathroom vent out roof).

The roof company makes (in my case) an aluminum stack cover for the vents that flares as it meets the roof, I watched then do the whole roof, They caulk the crap out it and then run the seamer down over it.. They also spent hours making sure the seams that surrounded my stove pipe was water tight.. Standing seam is great until they have to snip due to angle, if the roofer does what they should do, it will never leak..

IMO, putting screws on "L" brackets under the seems as opposed to putting external screws with rubber washers that degrade with sun is no comparison..

I do have screw down metal roofing on my out buildings and it works for now, I did install the screws on the top of the seam very carefully so that the screws aren't in the path of water and in the way of the snow coming down the roof..

 

[clemsonfor]

The fasteners on metal roofs will not last as long as the roof, you will have to rescrew at some point as UV and pollution etc will degrade that rubber.

 

[atsah]

No doubt..

 

[atsah]

Replacing the screws doesn't sound like something I want to do, not only are you going to need to install a new screw in the same hole but it will probably need to be a longer screw if you want it to stay put.. To me the screw down roofing is worse than shingles, when my screw down roof starts to leak, standing seam is what will be installed..

IMO, if you are going to install screw down roofing, make sure you use thick enough strapping so that you can install longer screws the next time it needs them..

 

[/pine]

The fasteners on metal roofs will not last as long as the roof, you will have to rescrew at some point as UV and pollution etc will degrade that rubber.

FWIW...
They make roofing screws that have zinc caps (domed washers) that protect the elasticized material that seals around the screw under the cap...they're sold most places that sell 5V and other metal roofing panels...

 

[clemsonfor]

Replacing the screws doesn't sound like something I want to do, not only are you going to need to install a new screw in the same hole but it will probably need to be a longer screw if you want it to stay put.. To me the screw down roofing is worse than shingles, when my screw down roof starts to leak, standing seam is what will be installed..

IMO, if you are going to install screw down roofing, make sure you use thick enough strapping so that you can install longer screws the next time it needs them..

Or find a larger diameter screw if they exist