One of the solar companies I've been talking to has just told me that my installation will cost quite a bit more because I have a slate roof. Why?
answered 2015-02-20 15:38:00 -0500
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We've spoken to a few of the installers in our network (EthnoSolar and Sunlight Solar Energy were particularly helpful) to get a deeper understanding of why installing a solar panel system on a slate roof costs more than installing on a standard asphalt shingle roof.
Basically, slate roofs are substantially more difficult to work on than asphalt shingle roofs for 2 reasons:
1) Slate roofs require special roofing expertise to work on
Asphalt shingles are soft, malleable and easy to waterproof/add flashing for. For these reasons, they're also difficult to accidentally damage. Most installers are trained to install solar panel mounting technology on shingled roofs as a matter of course, and because shingled roofs are so common, they have lots of experience doing so.
While slate roofs have longer lifespans (80-100 years if well-maintained), they are also much easier to accidentally damage; slate is essentially rock and is therefore difficult to drill through without cracking. A primary goal of your installation company will be to make sure that nothing they do voids your roof warranty. To this end, when a slate roof is involved, that may require them to sub-contract part of the work (e.g. the installation of the mounting brackets on the roof) out to a professional roofing company that knows how to work with slate. Since there are not many such contractors out there, their services tend to be quite expensive.
2) Slate roofs are generally more dangerous to work on
Slate roofs are slippery to walk on compared to shingles, thus requiring an extra degree of care and caution when work is underway. This means that a solar panel installation could take more time and therefore have additional labour costs.
Don't give up - shop around
We hope this is helpful. If you're very keen on going solar even in light of the higher costs associated with installing on a slate roof (it could still very well be worth it!), one way you could minimize costs would be to shop around for installers - our Solar Marketplace is a good place to start.
Asked: 2015-02-13 12:43:19 -0500
Seen: 563 times
Last updated: Feb 20 '15