Standing seam alternative for historic district
We are proposing an addition and deep energy retofit for a home in a historic district.
We have proposed a standing metal seam roof for the following reasons:
– twice the life of composite shingle; over it’s life significantly more economical
– after it’s useful life, it can be recycled (versus the composite alternative of the ~2 shingle roofs that will eventually end up in the landfill)
– zero penetrations for racking for panels (with proper planning they can clip directly to the seams)
We are unlikely to get this surface approved. Nearly everyone just uses to-be-landfilled shingles.
What other options do you recommend. In addition to environmental stewardship, we care about:
– lifetime cost
– ease / maintenance of integration with solar racking; leaks can happen and especially in a sealed home, with a foam roof, that’s a lot of material that would have to be stripped (and likely discarded?) for any serious repairs.
The homeowner intends to pass on the home, so thinking in full lifespan makes sense.
Thank you!
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I have stone coated steel tiles on part of my roof, they can be had in many "traditional" profiles. They look pretty good, very quick to install and similar longevity as standing seam. You would have to use mounting brackets designed for tile roofs for the solar mounts.
There are also a number of composite slate tiles as well. These are mostly plastic but still much more durable than shingles. I would be careful with these as some of them can look extremely fake even at a distance.
That sounds interesting - do you know what brand or product line you're using?
Mine are Metstar.
Every historic district is different, there is no logic or fundamental principles.
Around here, asphalt shingles wouldn't be allowed in a historic district, standing seam would be.
an "understatement" ... :)
Yeah, for the most part the Historic Preservation Office is what you would expect if you had a Renaissance Faire teaching history.
Asphalt shingles can be recycled into roadway paving or, in some cases, new shingles. Only a small percentage are actually recycled, but the potential is there for more.
Metal roofing is popular in my area but even so, traditional double-lock standing seam roofing costs up to twice as much as asphalt. It has twice the lifespan, or potentially more if painted in place once the original coating is worn, and if the house is not renovated. But on a lifetime cost basis, asphalt shingles and metal roofing aren't very far apart.
It's interesting what historic district commissions decide is important vs. what is not important. I love old homes, details and materials, but how is a petroleum-based shingle meant to look something like a wood or slate roof--and doing a very poor job of the fakery--considered historically correct, while standing-seam roofing, which is honest, durable, and traditional in many areas, considered not ok? And how are PV panels considered acceptable if a historic look is so important?
If you end up using asphalt shingles, you might consider switching from extremely-high-embodied-carbon spray foam to a low-embodied carbon insulation, and over-venting (or top-venting) the roof system so any leaks would be caught with the second waterproof layer.
What year are they trying to recreate?
The first asphalt shingles can out in 1900 Monticello had a tin roof almost 100 years before the first asphalt shingle.
Look around my guess is you will fund a few metal roofs in the district
Walta
The area was built heavily starting in the very late 1800’s
And yeah, the asphalt shingles in their current form are clearly no 'original' - but they became nearly universal by some decades later. Then in perhaps in rhe last 30 years "preservation" has become strictly enforced....
So both the asphalt shingles are lumped into "preserve whats here" - and obviously they can't enforce something like split cedar shingles ... so here we are....
Late 1800's standing seam galvanized roofs would have been everywhere.
I've done a bit of searching, haven't found any great sources with the kind of examples that would help me convince a Commission of this.
In particular what types of architectual styles they were common on. This house is originally a Craftsman. This is a low/mid budget house for sure ... what would have it used for it's original roof?
Similarly - asphalt shingles also existed back there. But I assume they look very little like our modern varieties ... any resources that demonstrate how asphalt today is wildly historically INaccurate would also help ... although really this district is best described by contrasting "recreate" vs "preserve" - it's more the latter, what's here now, keep it that way. (illogical, i know)
I think of Craftsman as the first third of the 20th century.
Depending on your location, the age of the house and the original construction budget, there is a good chance the roofing was wood shingles or shakes. (Shingles are sawn; shakes are split and have a rough face.) You might do some research in books and magazines on Craftsman-style architecture. Here are a couple of overview articles:
https://www.oldhouseonline.com/repairs-and-how-to/roofing-historic-buildings/
https://artsandcraftshomes.com/exteriors/the-nostalgic-roof