Metal Roofing: The Sustainable Roofing Choice
In a previous blog post, I discussed the many cons of asphalt shingles. Now I will discuss a better alternative to asphalt shingle roofs: Metal Roofs. Now I know some will say that metal roofing has high embodied energy and is not on the sustainable list, but I have to disagree because it last or out lasts probably 3 of 4 even more asphalt shingle re-roofs, this is a serious consideration. Greenovision believes strongly in metal roofs as they last very well, sometimes up to 100 years. The thickness of metal is important- thinner sheeting will dent if large hail hits, which as the climate change is suggesting, will occur more frequently. 24 gauge is heavy; 26 a bit thinner, but both will work fine.
I like standing seamed panels that are 18″ or less; they will not leak if detailed correctly. A panel larger than 18″ will oil-can when it heats and cools. Expansion is an important consideration, but more metal roof companies are well aware of this and it is mostly a problem in very large roofs. This image shows additional panel structure or striation to help avoid oil canning.
Depending on where you live and the type of home you have, but may have Historic Preservation rules. Historic Societies sometimes make a big deal about metal roofing not matching the existing vernacular, which in many very old homes is often slate. Slate roofing is excellent, but very expensive. Unfortunately, Historic Societies consider asphalt a reasonable simulation in look, but they never consider its longevity. If you must go this route a simulation slate from Eco Star is a 50 yr product that is made fro 80% recycled materials consisting of old tires and plastic. From the look of it on my neighbors home it has handled hail very well and looks better than asphalt , it does look like slate. I have never used the product but I think I would it I had to. Below is a picture of it on my neighbors home Adrien Tanguay.
When considering using a metal roof, it is important where the snow will fall once shed from the roof. Metal roofs eliminate snow as soon as there is a melt and when it slides off, it usually does so in one giant avalanche. Below is an example of snow shed from a metal roof onto an awning and then from that. It can really pile up.
There are snow guards that can be installed to the roof that hold the snow so that it doesn’t fall on a walkway or door way all at once. These work well in that they allow the snow to melt on the roof in areas of concern. There are different styles of snow guards. Gutters often need to be installed in these places. If your home has problems with ice damning, metal roofing will help solve problem because ice cannot cling to metal as it does with asphalt shingles.
Metal roofing comes in a wide variety of pleasant colors to match details of your exterior. Most metal is a galvanized steel aluminum alloy, which resists rusting. The color coatings need to be quality. Anyone that gets on the roof should be careful to not scratch it as metal is very slippery and is not as attractive when scratched.
Metal roofs cost more up front than asphalt shingle roofing, but because metal last much longer than asphalt shingles, the home owner ultimately sees huge maintenance savings. Also because metal lasts longer, it is a much more sustainable and environmentally-friendly alternative to asphalt.
Here is a company that shows some images of metal roofing and application. If you have any questions about my experience with metal roofs, please feel free to contact me.