Metal Roofing vs. Asphalt Comp.

[madrone]

Did a search, but didn't come up with much. Google results are all from roofers with a particular bias. I'm going to need a new roof next year, and I'm wondering if the price of a metal roof is worth it. I like the idea of less weight on my old, under-engineered house, and the lack of maintenance. Anybody got info?

 

[Cearbhaill]

I can't wait to hear- I am going to be needing one in the next few years and have my heart set on metal. Our last house saw multiple periodic reroofs and one that would last on this new house is tempting.

 

[jdemaris]

Did a search, but didn't come up with much. Google results are all from roofers with a particular bias. I'm going to need a new roof next year, and I'm wondering if the price of a metal roof is worth it. I like the idea of less weight on my old, under-engineered house, and the lack of maintenance. Anybody got info?

I would never, use anything again but metal as long as I'm living in the northeast. It can virtually last forever if taken care of, and does a fanstastic job at shedding snow.

On some jobs, a metal roof cost no more than asphalt - but that depends on several things. Often, older houses need new sheathing before new asphalt can be put on (5/8 CDX plywood etc.). If a steel roof is going on, nailing strips that criss-cross the rafters, spaced 24" apart go on instead. Prices keep changing too. Last year, I was buying painted steel roofing - 36" wide - for $1.50 per foot. I know it's gone up recently.

Here in the snow-belt, most buildings - barns and homes were metal roofed (usually soldered seams) dating back to the 1800s. Then asphalt got popular, and now steel is getting used again - especially in the highest snowfall areas in the Adirondacks.

My house still has an 1860s steel roof on it. Same for one of my barns. A new house I built has the new type steel - and I chose exposed fasteners that makes it cheaper than hidden.

One negative I've seen is . . . a few homes with steel roofs in very hot areas - where the paint peeled right off. Don't know what brand it was, and don't know if that is common since I've never worked or lived in a hot area.

About roof pitch -if your's is steeper then 5/12, you're going to have trouble walking it in steel. 5/12 I can walk on pretty well when dry if wearing good sneakers. It's another reason why I like exposed fasteners. It gives you something to catch your foot on.

 

[madrone]

Thanks. Snow's not much of an issue here, but then, neither is sun. I've got a decently steep pitch, but my roof is higher than I like to be anyway. That's part of my interest in steel, not having to go up there. I'm interested in hearing about the older roofs. Do you paint regularly? Reseal fasteners?

 

[glassman]

For whatever this is worth, I have a very good friend that recently retired from 30 years owning a roofing business, he is 65 yrs. old. He said he would not put a metal roof on any home. The biggest problem he said is when you use 2 x 4's they act as dams on top of the roof, causing wet spots, mold, bacteria etc. His opinion is that when a metal roof gets cold, then warm, it will condensate, and the condensation drips onto the old asphalt shingles, and then the 2 x 4's hold the water. He also said that after a few years, the metal moves with the sudden temp changes, he has seen them move enough to leave holes bigger in diameter than the fasteners with the rubber washers on them. He said after about 20 years, you may need to remove and replace everything down to the trusses. I have another good friend with a metal roof that is about 20 years old, and he has gotten 6 leaks this year, and has all but 2 patched. He cannot find the last 2 leaks. He gets several leaks a year now too. I have been considering a metal roof also, that is why I have done tons of research in the last couple of years. My neighbor just had one installed, and the builder did not use 2 x 4's but instead he layed a rubber type membrane down where they used to install 2 x 4's so when the fasteners go through the steel, they will go through the rubber membrane, which is supposed to keep it more water tight. We live in northern lower michigan, and we are in a snow belt region, so there is a lot of controversy around here about metal roofs. Our lumber companies are now making metal shingles, several different styles. I am getting a price on a metal roof, and the metal shingles, when I get a rough idea, I will pass the cost difference on to you. Good luck,,,,,,,ed

 

[jdemaris]

For whatever this is worth, I have a very good friend that recently retired from 30 years owning a roofing business, he is 65 yrs. old. He said he would not put a metal roof on any home.

I've been in the business, off and on, almost as long as your friend. I started working for contractors in my young teens and I'm 60. Speaking for myself and what I've seen, the idea of standing-steam exposed-fastener metal roofs was never even an issue until 20-25 years ago, and - at that time, some of the material was poorly designed, and methods of installing it had not been time-tested or proven. Many at that time were nailed, not screwed - and some were done on the standing seams, and some below the seams on the lows |(as is the norm now). The old metal roofs (100 years ago plus) were different, since they had soldered seams. As to the problems you've mentioned - much depends on the installation, like just about anything. I've done several that have been up for over 20 years with no unusual leak problems, or enlargement of the holes the screws fasten through. Some roofs, if you pay a premium, have no exposed screws, and no such holes at all.
But, yeah - there are some real slop-jobs done. When doing a house or other type of heated building, I much prefer no nailers, and like to use a flat 5/8" or better plywood base with a good, leak-proof vapor barrier. Then the steel roofing goes directly over it. In regard to the mold issue with nailers - I haven't seen it - but then again I wouldn't put any steel over old asphalt as you mentioned. Too much weight - it ought to be stripped off.

In the past 10 years, seems just about every other house in the high-snow areas of the Adirondack mountains is steel now. And, they get more snow that anywhere in the lower peninsula of Michigan (not counting a few lake-effect areas). I can't say I've surveyed the area for complaints - but I suspect if there were chronic problems, it would not be getting used more and more in that area - and it is. Many are expensive, high-end houses.

Again, I love it - mainly because it heats up fast when the sun comes out and the snow slides off quickly. I also like the way it looks - but the judge is still out on how long these paint coatings will last before they have to be redone. On my old soldered seam roofs, they need a coating every 30 years or so - but they were never painted to start with - just galvanized - and some that I have are 150 plus years old. In fact, in my area, the only old soldered-seam roofs I've seen fail did so in severe windstorms when they peeled off like the tops of sardine cans.

 

[glassman]

hi jdemaris,
most of the metal roofs I have seen being installed around here, they are going right over the old shingles, and using the 2 x 4's. The only one I saw without the 2 x 4's was the one done last week on my neighbors, he used the rubber strips instead of 2 x 4's, but still went over the old shingles. I like your idea about stripping old shingles and then the 5/8 plywood with vapor barrier. I am not trying to talk someone out of using metal at all, just an opinion I heard from someone I trust. Sounds like your doing a good job with your roofs, keep up the good work, and good luck,,,,,,,,ed

 

[velvetfoot]

My place is 5 years old and came with a gray metal screw on roof.
It has a plywood decking. Not sure about a vapor barrier.
The sliding snow could kill you, but I don't know, I'm not crazy about adding those little do-hickeys.
It doesn't slide off as easily off the shallower porch roofs.
It comes down with quite a crash-hopefully the porches will hold up.
Also, I don't think rain gutters work that great with them-one gutter guy said that he wouldn't install them on a metal roof 'cause they get ripped off. I don't know but I don't like them anyway.
It's a bit noisy, but mostly because of the rain on the porch, not as much on the roof which covers a good layer of fiberglass insulation.
I don't know about the longevity of screwed on roofs, but if the washers fail over time, they could be replaced I guess. At least you can see them.

 

[Highbeam]

I ripped off an older, leaky, exposed screw, metal roof and replaced it with asphalt. I am very happy with the switch. I like the sound of rain and it rains alot in WA but that metal roof was noisy. Too noisy for a local guy even. Could be because of the lack of insulation in my attic but I hated the nosie. The leaks made me a bit biased too.

Asphalt roofs last a long time.

 

[peakbagger]

Most of the roof installers in my area will not install a new roof with steel unless they install a EPDM underlayment under the roofing. Basically when the roofs leak, there is no good way to fix it and the EPDM, makes sure that the inevitable leaks dont get into the roof deck. Straight runs on steep pitches seem to work well, but any roof penetrations make thing difficult and you are very dependent upon the quality of the installer. Unfortunately problems with these penetrations dont appear for several years and by then the roofer is out of business or the staff has turned over.

The problem with snow sliding is significant, I have seen Sch 80 PVC plumbing vents sheared off by snow sliding and have seen fence posts broken by the speed of the snow coming off the roof. The solution of installing snow clips is frequently added on, but very rarely do they last the life of the roof.

Overall I think the best choice is premium shingle installed over an EPDM underlayment. Barring unusual conditions, a premoum shingle can go 25 to 30years these days and a second roof can be installed before stripping giving 50 years.

If you do go with a steel roof, the galvalume panel with hidden clips and rolled seams are about the best.

 

[jdemaris]

The problem with snow sliding is significant, I have seen Sch 80 PVC plumbing vents sheared off by snow sliding and have seen fence posts broken by the speed of the snow coming off the roof. The solution of installing snow clips is frequently added on, but very rarely do they last the life of the roof.

No argument there. I've had our entire front porch smashed to pieces from snow and ice slides. But, I still prefer it over the alternative - and have worked around the snow-crash problems.

In our particular area - in the winter- we often get conditions when ice dams up on the eaves. Gutters will not work here with any roof unless you stick electric heating elements into them. Some people in my area actually take them off every winter, and put them back on in the summer. With an all-steel roof, it cleans itself much better and the ice-dams don't happen along as there is sufficient pitch. The steel usually eliminates the need to shovel roofs all winter (those that are not steep enough to self-shed).

I suspect steel has gotten so popular in the Adirondacks due to the fact that there is high snowfall and many houses sitting empty in the winter. Having steel eliminates the need to have somebody shovel the roofs all winter.

 

[glassman]

jdemaris,
I installed a gutter shield over my rain gutter, it slides up under the shingles, and keeps leaves out, only trouble is if we get warm/cold days/nights, sometimes I get a partial freeze in the gutter itself, but its never been enough weight to break the gutter brackets,,,,,,ed

 

[jdemaris]

jdemaris,
I installed a gutter shield over my rain gutter, it slides up under the shingles, and keeps leaves out, only trouble is if we get warm/cold days/nights, sometimes I get a partial freeze in the gutter itself, but its never been enough weight to break the gutter brackets,,,,,,ed

Yes, but weather differs all over. I have a house and small farm in the lower peninsula of Northern Michigan - in Presque Isle County. I've never had the ice-dam issues there - that I have here in this part of New York. I also have in-laws that live in Alpena, MI - they don't have the same weather or problems either. Seems here in this part of NY, due the mountains and valleys, we have many microclimates where 20 miles can make a difference. Much of MI seems to be more buffered with less extreme swings due to the Great Lakes. Now, the UP can be a different story in some areas - at least from what I've seen.

Here, when snow collects on an ashphalt roof, then gets partially warmed by the sun, it starts to run off. Then, if the temps hit just right - it all jams and freezes on the eaves. The weather needs certain events in a certain order for that to happen - but it is common here. Easiest answer is to have a roof-rake and remove snow from the roofs when possible. Some people install electric heater grids on the eaves that also seem to work well.

I don't use gutters up in the air anymore. Mine are on the ground and that works great for my place.

 

[velvetfoot]

Got Lake Effect?
(Hey, I lived in Oswego for a year and a half.)

 

[SnaykeByte]

I installed a ProRib steel roof on my house this year. It is 16" wide pieces and it interlocks together meaning that you screw the first piece down using the special screws that you order with it, (no seals needed), and the next piece locks over the first completely covering the screws making it impossible to ever leak. I love it!

 

[Hogwildz]

I installed a ProRib steel roof on my house this year. It is 16" wide pieces and it interlocks together meaning that you screw the first piece down using the special screws that you order with it, (no seals needed), and the next piece locks over the first completely covering the screws making it impossible to ever leak. I love it!

Put on much of this type in my years as a roofer. Good stuff. You can get painted steel, galvalume or aluminum.
All have a 50 year Kynar finish. Of course the aluminum is the top shelf. But expensive.
Yes they screw down to the decking on one side, the the next one snap locks over top of the seam.

The cheaper barn grade metal roofing is not near as good, is face nailed or screwed, and basically overlaps at the seams. Some use a sealant or double sided tape there.
Problem is, after time, the neoprene washers on the nails or screws dry rots & deteriorates, eventually falling apart and letting leaks appear under heavy rain &/or snow loads.

As with all roofing, each has their pluses & minuses.
Metal roofs are louder. Even with insulation, the rain can drive some nuts, while others love the sound.
I myself disagree with putting the metal roofing on lath. It can & will oil can under snow loads, or even in the summer in the sun.
And the face nailing or screwing leaves no room for expansion & movement. It should be installed over a vapor barrier. Roofing felt, or as we used to use on the old style hand formed lock seam & solder roofs, we used rosin paper. Then a solid decking underneath. Plywood or board backed insulation. Usually polyisocyanurate (spelling).

The lock seam type has slots that screws are fastened through, not unlike vinyl siding nail slots.
This leaves room for expansion & contraction, and leaves less chance of oil canning of the metal.
Lock seam is also a thicker material and that also leaves less chance of oil canning.

The thinner barn roof metal, pretty much same as sold at the box stores, will work, but won't last as long as far as maintenance,
and the finish will fade much sooner.

With many things, when it comes to metal roofing, or basically any roofing, you get what you pay for.
Either shingles or metal will last a long time. If you don't cheap out on the materials and the installer installs properly without cutting corners.
Its all a matter of budget & preference.

Don't waste your time with gutters with a metal roof. You will soon learn it gets expensive to constantly replace &/or pay someone to reinstall every time the snow & ice take them to the ground.
On steep pitches, I do suggest the snow cleats. At least over doorways or areas that need safe passage below.

 

[PaulRicklefs]

In Northern Saskatchewan those who have exposed-screw metal roofs all get leaks eventually. Not necessarily because of poor installations, not necessarily because of our very extreme temperature variations (+100 F to -60 F), nor because of high snow loads, but because of the ravens that pull the rubber grommets out from under the screws!

But as for my roofing opinion, you are wiser to install a metal roof if you have a high snow area otherwise I believe asphalt will give you less trouble over it's 20-30 year lifespan than a metal roof.

There is absolutely no such thing as a maintenance-free roof.

 

[d.n.f.]

I know two roofers and both hate metal.
You never want to walk on it without a safety line.
The fasteners will leak.
Shedding snow will remove gutters and every year it removes people if the snow falls on you.
If the roof is not steep enough it will not shed and you are back to the tremendous snow loads.
Galvanized is white-trash ugly. No offense to the white-trash guys out there.
Coloured metal fades. Need repainting. Do you want to repaint your roof?

Newer shingles last forever. A 20 year shingle is now a budget shingle these days. 30 to 50 year are the norms.

However when I build my woodshed it will have a metal roof.
Go figure.

 

[PaulRicklefs]

I know two roofers and both hate metal.
You never want to walk on it without a safety line.
The fasteners will leak.
Shedding snow will remove gutters and every year it removes people if the snow falls on you.
If the roof is not steep enough it will not shed and you are back to the tremendous snow loads.
Galvanized is white-trash ugly. No offense to the white-trash guys out there.
Coloured metal fades. Need repainting. Do you want to repaint your roof?

Newer shingles last forever. A 20 year shingle is now a budget shingle these days. 30 to 50 year are the norms.

However when I build my woodshed it will have a metal roof.
Go figure.

That's about all i'd put a metal roof on is a shed. Another fine use for metal roofing is on the inside of my garage walls.

 

[Jay H]

one more consideration, especially if you are in a forrested area of Willamette Valley is to think of a flame retarded roofing system that consists of metal versus wood. It will help prevent your house from getting set on fire from embers if there is a forrest fire near you... I think people living out west these days have to consider the fact that forrest fires are becoming an increasing hazard to home owners who live in the wilderness and suffer through droughts.

Jay

 

[madrone]

Thanks, all. That's why I come here.

 

[woodsman23]

I live south of buffalo ny metal is great for our area, try it you will like it.

 

[SnaykeByte]

I know two roofers and both hate metal.
You never want to walk on it without a safety line.
The fasteners will leak.
Shedding snow will remove gutters and every year it removes people if the snow falls on you.
If the roof is not steep enough it will not shed and you are back to the tremendous snow loads.
Galvanized is white-trash ugly. No offense to the white-trash guys out there.
Coloured metal fades. Need repainting. Do you want to repaint your roof?

Newer shingles last forever. A 20 year shingle is now a budget shingle these days. 30 to 50 year are the norms.

However when I build my woodshed it will have a metal roof.
Go figure.

That's about all i'd put a metal roof on is a shed. Another fine use for metal roofing is on the inside of my garage walls.

Yeah....................I remember when I had my first beer, made me say silly things too. What do you have against steel roofing? Have you checked out the technology concerning metal roofs in the last 30 years or so?

 

[d.n.f.]

Hey I love the way it looks.
I would put it on a house if my roof was steep enough. It is not and I will be replacing shingles with..... shingles.
Make sure the snow will not dump in front of my door (extra shovelling and it may kill you).
Flame protection is excellent from burning embers from forest fires.
Expensive though., and walking on it can be quite sporty.

 

[firefighterjake]

Right up front I have to admit that I am biased against metal roofing . . . but not for any of the other reasons listed (in fact I actually like the look of a colored metal roof on some types of homes and like the idea of not having to dig out my snow rake after every snowstorm).

My bias is from the firefighting side of things. If we're fighting a house fire and the steel roof gets wet things get wicked slippery up there on the roof (although we can and will throw a roof ladder down in this case) . . . ditto for chimney fires which always seem to be called in around 2 a.m. in middle of a January blizzard. My other issue is that asphalt roofs tend to allow the fire to burn through them creating a natural venthole oftentimes . . . whereas metal roofs tend to trap the heat and burn up the underneath (makes it a bit hotter and smokier for us inside and a bit dangerous if someone isn't paying attention to how the fire has been burning.)

I'm also a bit biased since I would often shovel off my parent's front porch when I was a kid back in the 1970s and 80s and then ten minutes later all that snow on the roof would come down in a rushing roar and I would have to start all over again.

This said . . . my main reason for prefering asphalt roofing over metal roofing is that if I need to make a repair I personally have the skills and ability to more easily make that repair with asphalt vs. metal . . . however this is just me and my own skill level.