Metal roofing vs asphalt

[JHZR2]

I have a question about metal roofing, but it’s slightly different I think.

My understanding is that generally metal roofing is more expensive. My understanding also is that much of that is due to the work required with offsetting and overlaying it so that it’s not noisy when it rains. So work to make it good for a house with people living underneath.

I will at some point need to replace roofs in both of my garage buildings. Neither have people living underneath, neither have rain noise concerns, neither need insulation.

For applications like this, is there a potential that metal is the better option? A cheaper, longer lasting option? I like the lack of seams, longer pieces, etc.

I know the asphalt guys get teams of illegals to pay dollars an hour to work in the sun, and do it Uber cheap (and still afford souped up big pickup trucks). But is there an opportunity for a cost effective metal roof with better longevity and performance on outbuildings? I’ve seen lots of very old wood barns with very old metal roofs all over the country…

 

[demarpaint]

No brainer imo. From what you described, I'd go metal. Some people don't like the look for it, for stand alone garages it would be my choice.

 

[JTK]

Had an Amish crew put a metal roof on my home last year. They went over the top of the existing 15yr old shingles with rough cut true 1"x4" boards, then screwed the roofing to the boards.
The only issue for me with metal is the sliding snow and ice. If it gets thick and heavy enough it will take plumbing vents and such with it, so you need adequate snow bars. In terms of noise it's a non issue. No difference at all.

 

[oldcodger]

Yes metal roof is the proper choice. Be aware that some metal roofs are not maintenance free. I know several people who have had leaks when the neoprene sealing washers under the hold down screws harden and crack. I have seen some guys up on a metal roof replacing the screws and washers.

 

[manicrodder]

Had an Amish crew put a metal roof on my home last year. They went over the top of the existing 15yr old shingles with rough cut true 1"x4" boards, then screwed the roofing to the boards.
The only issue for me with metal is the sliding snow and ice. If it gets thick and heavy enough it will take plumbing vents and such with it, so you need adequate snow bars. In terms of noise it's a non issue. No difference at all.

The Amish use power tools?

 

[JTK]

The Amish use power tools?

They had top notch battery powered tools.

 

[tc1446]

The old barns/houses used a heavy metal...I think it was galvanized but am not sure. I have 20 X 24 built in 1929 by my Dad with one of those roofs. Rusted but still substantial and no leaks. Nearly all buildings back then used that type metal roof.

 

[nomas]

The Amish use power tools?

Sure , why not ? But they rode horses and buggies to the jobsite I'll bet .

 

[bcossa2020]

Commercial contractor here.....
If your roofline/ shape is fairly straightforward (and I suspect as a barn, it is) and the slope is greater than 2 in 12, then metal is an excellent solution, particularly since it is noncombustible. I would not recommend metal for low slope roofs nor for roofs that have lots of valleys, slope changes, different height intersection, etc. This all requires hand made metal flashing and few workers seem to either use the proper detail or have the skill to install properly for a watertight installation.

I would not consider a screw down roof per what Oldcodger said above and regardless of what any salesperson might tell you. The neoprene washers shrink, the screws rust, they break when you remove them and you need a larger screw and washer for the replacement. The metal also rusts where the screw penetrates the metal and contributes to wallering out the hole. You can caulk till the cows come home but it will continue to rust. No thanks.

The best metal roofs have a Kynar paint finish over a galvalume metal. You would want to be sure to have ice dams installed as part of the original installation. The paint finish is 20 year.
Frankly you can get a typical shingle roof for probably less than 1/2 the cost of the metal. Properly installed, either roof will give many years of service, but my experience is that the metal is substantially more expensive for the 20 year materials and a standing seam (i.e. Not screw down) installation.

 

[Warstud]

Sure , why not ? But they rode horses and buggies to the jobsite I'll bet .

If they use power tools I'm sure they drive Tesla's

 

[nomas]

If they use power tools I'm sure they drive Tesla's

Nope . They will ride in an automobile but they will not own one .

 

[cpayne5]

Continuing the Amish discussion...

I'm in Northern Virginia and had an Amish crew build my pole barn garage. An "English" man drove them down (and they stayed in a local hotel each night). The used corded and battery power tools and one even had a cell phone. I questioned him about the phone and he said that they can receive permission from the church to use technology in instances where it helps support the family. ie, work items. He indicated that each item is requested/permitted on a case-by-case basis.

 

[xgmad]

I would go with asphalt, is heavy winds something to consider?

If you do have heavy winds I would definitely go with metal roofing.

 

[2strokeNorthstar]

Yes metal roof is the proper choice. Be aware that some metal roofs are not maintenance free. I know several people who have had leaks when the neoprene sealing washers under the hold down screws harden and crack. I have seen some guys up on a metal roof replacing the screws and washers.

Yep, nothing is maintenance free forever. I spent a lot of time on old metal roofs at past jobs. You can’t seal over sealant either. The metal needs to be clean to seal like anything else.

 

[JHZR2]

Had an Amish crew put a metal roof on my home last year. They went over the top of the existing 15yr old shingles with rough cut true 1"x4" boards, then screwed the roofing to the boards.
The only issue for me with metal is the sliding snow and ice. If it gets thick and heavy enough it will take plumbing vents and such with it, so you need adequate snow bars. In terms of noise it's a non issue. No difference at all.

I wouldn’t want the added weight of the old asphalt.

 

[JTK]

I wouldn’t want the added weight of the old asphalt.

I get that. I don't know the numbers, but I'm thinking metal is lighter than adding shingles over shingles.

The other thing with metal is even if you did tear off the shingles down to bare wood, you still need a barrier between the metal roof and the roof decking. I'm not sure what they'd use given I've never seen it done that way. I'm assuming it would be ice and water shield.

I don't doubt that the screws are the weak spot, but I have neighbors, friends and family that have had these roofs for 30yrs and the screws/grommets are still doing their thing. I know of no one who's had to replace screws. You hear this all the time. I personally haven't ever seen it.

I kind of lucked out on cost given I had our metal roof done early in the pandemic, just after they did my FILs roof. Cost was a fraction of what a outfit would have charged me to do a tear off and re-do with shingles. My existing shingles could have lasted another 10yrs, I was just sick of digging buckets of aggregate out of my gutters.

 

[bcossa2020]

I get that. I don't know the numbers, but I'm thinking metal is lighter than adding shingles over shingles.

The other thing with metal is even if you did tear off the shingles down to bare wood, you still need a barrier between the metal roof and the roof decking. I'm not sure what they'd use given I've never seen it done that way. I'm assuming it would be ice and water shield.

I don't doubt that the screws are the weak spot, but I have neighbors, friends and family that have had these roofs for 30yrs and the screws/grommets are still doing their thing. I know of no one who's had to replace screws. You hear this all the time. I personally haven't ever seen it.

I kind of lucked out on cost given I had our metal roof done early in the pandemic, just after they did my FILs roof. Cost was a fraction of what a outfit would have charged me to do a tear off and re-do with shingles. My existing shingles could have lasted another 10yrs, I was just sick of digging buckets of aggregate out of my gutters.

My experience with the screws has been on metal buildings, which are infamous for shaking/moving which would certainly contribute to loose screws. One can’t argue with the real world experience of you and your acquaintances....

We used to put the metal over a layer or two of building felt on plywood, with ice and water shield at valleys and eaves. It’s not uncommon now to see 100% ice/water shield for underlayment, which is about as close to watertight as one can get......

 

[Lubener]

Some excellent comments. Myself being in my late 50's, would never consider a metal roof now and would go with a premuim asphault product. I doubt that I would live long enough or stay put for a long time to reap the benefit of an expensive metal roof. If you are young and plan to stay put for a very long time, go metal.

Don't know why some are brain washed thinking Amish done is a big deal. To me, it is not noteworthy.

 

[JTK]

Don't know why some are brain washed thinking Amish done is a big deal. To me, it is not noteworthy.

Have you had a bad experience with them?

For me, they respond quickly to inquiries, they show up when they say they're going to show up. They do decent work and for a fraction of the cost of a conventional outfit.

It's another situation where I've personally never heard someone use their services and say never again.

 

[JHZR2]

I get that. I don't know the numbers, but I'm thinking metal is lighter than adding shingles over shingles.

The other thing with metal is even if you did tear off the shingles down to bare wood, you still need a barrier between the metal roof and the roof decking. I'm not sure what they'd use given I've never seen it done that way. I'm assuming it would be ice and water shield.

I don't doubt that the screws are the weak spot, but I have neighbors, friends and family that have had these roofs for 30yrs and the screws/grommets are still doing their thing. I know of no one who's had to replace screws. You hear this all the time. I personally haven't ever seen it.

I kind of lucked out on cost given I had our metal roof done early in the pandemic, just after they did my FILs roof. Cost was a fraction of what a outfit would have charged me to do a tear off and re-do with shingles. My existing shingles could have lasted another 10yrs, I was just sick of digging buckets of aggregate out of my gutters.

Good points!

Like an additional permanent weatherproof membrane…