Mounting with Hardishake fiber cement roof and skip sheathing

[tygunn]

What mounting options are there for roofs with cement fiber shake shingles applied over top of a skip sheathed deck?

I've solicited quotes from two solar providers in my area (Bay Area) and the responses were:
1. Entire re-reoof required.
2. Area under the panels needs to be re-roofed with asphalt shingles.
Clearly (1) would be a very expensive proposal given that my roof is in reasonable shape and not requiring replacement for some time.
(2) does not sound appealing to me as it adds thousands of dollars (I presume; they never said how much it would be) to the installation cost, and I will likely need to re-reoof during the expected life of the panels.

[ButchDeal]

I think the QuickMount shake mounts QMLC will work as well as the QBase shake

http://www.quickmountpv.com/downloads/datasheet/QMPV-datasheet-QMLC-ClassicShake-web.pdf

http://www.quickmountpv.com/products/shake-mount.html?cur=2

http://www.quickmountpv.com/products/qbase-shake-slate-mount.html

[littleharbor]

Hardi products are awfully tough, I know, but there's no reason you couldn't mount your array over them. Obviously it is going to be more labor intensive and may require some in attic work to provide additional backing where necessary. I would think from the solar contractors point of view he would prefer a quick and easy comp roof install.

[J.P.M.]

For a lot of reasons, changing roofing materials under an array is not a good idea, both in terms of roof integrity against ingress of water and other things (the biggest reason), but also what happens after the array is moved/removed for what are currently unforeseen and unplanned for reasons. The only benefit is to the installer as it will save a bit of time( == $$), and a few $$ from unavoidable (but not much) breakage of brittle tile with no advantage for the homeowner. FWIW, my HOA does not allow changing roof materials under an array. All roofs are either flat concrete tile or mission tile.

The issue of removing tile under an array and replacing with comp. shingles only became an issue around here about 5 yrs. ago, when, I suspect, some peddler more concerned about money than doing a quality job broke the ice and all/most vendors followed, claiming competition as justification for the race to lower quality and more profit. Before that, it never happened.

The HOA's Arch. Comm. dug in it's heels on this one and went to the mat with one well known and usually reputable vendor. After word got out (rather quickly) to other vendors, the issue stopped being an issue - at least in my HOA. There appears to be no affect on price as beat as I can see from looking at contracts and comparing to the CSI data.

I don't know if your product is more/less prone to breakage than std. mission tiles, but those mission tiles are pretty brittle, tending to break if you look cross eyed at them. A liitle more care is necessary, but it isn't like the vendor didn't know it up front.

Keeping the same material uniformly over a roof will help avoid problems. Changes in materials and sealing methods will create opportunities for problems which will be made worse by the fact that the transitions will be mostly out of sight (under the array) and therefore out of mind, and equally bad, probably inaccessible being under the array, and therefore requiring fooling with the array when the created problems rear their heads - and they will.

Take what you want of the above. Scrap the rest.

[tygunn]

I think the QuickMount shake mounts QMLC will work as well as the QBase shake

http://www.quickmountpv.com/downloads/datasheet/QMPV-datasheet-QMLC-ClassicShake-web.pdf

http://www.quickmountpv.com/products/shake-mount.html?cur=2

http://www.quickmountpv.com/products...ate-mount.html

Yes, both of those seem like reasonable options. Especially the qBase shake which shows installation on a slate tiles in the installation instructions.

I wonder if it would be useful to look into getting a roofing company to install the roof mounts. In terms of a potential DIY install, that is the only part of the process I don't feel confident with.

[tygunn]

Hardi products are awfully tough, I know, but there's no reason you couldn't mount your array over them. Obviously it is going to be more labor intensive and may require some in attic work to provide additional backing where necessary. I would think from the solar contractors point of view he would prefer a quick and easy comp roof install.

I had quotes from SunRun and SunWorks, both large contractors. So I can see how they'd be wanting to go for volume and just get it done.

Attic work would unfortunately not be possible except perhaps in the top 1/4 of the roof. The bottom 3/4 of the south-facing roof is exposed as a cathedral ceiling in the interior. The top 1/4 is exposed to the attic, however.

Maybe I should look into some of the smaller installers.

[tygunn]

For a lot of reasons, changing roofing materials under an array is not a good idea, both in terms of roof integrity against ingress of water and other things (the biggest reason), but also what happens after the array is moved/removed for what are currently unforeseen and unplanned for reasons. The only benefit is to the installer as it will save a bit of time( == $$), and a few $$ from unavoidable (but not much) breakage of brittle tile with no advantage for the homeowner. FWIW, my HOA does not allow changing roof materials under an array. All roofs are either flat concrete tile or mission tile.

The issue of removing tile under an array and replacing with comp. shingles only became an issue around here about 5 yrs. ago, when, I suspect, some peddler more concerned about money than doing a quality job broke the ice and all/most vendors followed, claiming competition as justification for the race to lower quality and more profit. Before that, it never happened.

The HOA's Arch. Comm. dug in it's heels on this one and went to the mat with one well known and usually reputable vendor. After word got out (rather quickly) to other vendors, the issue stopped being an issue - at least in my HOA. There appears to be no affect on price as beat as I can see from looking at contracts and comparing to the CSI data.

I don't know if your product is more/less prone to breakage than std. mission tiles, but those mission tiles are pretty brittle, tending to break if you look cross eyed at them. A liitle more care is necessary, but it isn't like the vendor didn't know it up front.

Keeping the same material uniformly over a roof will help avoid problems. Changes in materials and sealing methods will create opportunities for problems which will be made worse by the fact that the transitions will be mostly out of sight (under the array) and therefore out of mind, and equally bad, probably inaccessible being under the array, and therefore requiring fooling with the array when the created problems rear their heads - and they will.

Take what you want of the above. Scrap the rest.

I was definitely not a huge fan of the idea of changing roofing materials under the array, hence when it was suggested it was pretty much a non-starter for me. That and I really don't feel like paying extra to have that done (which was implied, but never explicitly quantified).

I've never really dealt with mission tiles. Given the condition of my roof it doesn't look like I have the specific year of hardi-shake shingles that got embroiled in a class action lawsuit from premature failure.

[J.P.M.]

I had quotes from SunRun and SunWorks, both large contractors. So I can see how they'd be wanting to go for volume and just get it done.

Attic work would unfortunately not be possible except perhaps in the top 1/4 of the roof. The bottom 3/4 of the south-facing roof is exposed as a cathedral ceiling in the interior. The top 1/4 is exposed to the attic, however.

Maybe I should look into some of the smaller installers.

Or at least better quality installers. Sunrun is one of the bottom feeders around here.

My roof is similar to yours with some of the array over a cathedral ceiling. I had no particular attachment concerns except for some extra care ensuring to hit the rafters where visual access was not possible. Just hire professionals who take time to do a job in a professional manner - and then, in the case of roof penetrations, watch the holes being drilled - That is, verify.

Quality may cost a bit more up front (but probably less than you may think, if at all more), but less in the long run.

[tygunn]

Or at least better quality installers. Sunrun is one of the bottom feeders around here.

My roof is similar to yours with some of the array over a cathedral ceiling. I had no particular attachment concerns except for some extra care ensuring to hit the rafters where visual access was not possible. Just hire professionals who take time to do a job in a professional manner - and then, in the case of roof penetrations, watch the holes being drilled - That is, verify.

Quality may cost a bit more up front (but probably less than you may think, if at all more), but less in the long run.

But they have presence in Costco, they must be good right ? Heh.

I'll take a look at other installers to see what they say. It sounds like this should be doable in a more reasonable matter. I'm willing to pay more for a proper quality installation.

In the mean time I will proceed with some energy upgrades (attic insulation, etc) so that I can get away with less panels.

[J.P.M.]

But they have presence in Costco, they must be good right ? Heh.

I'll take a look at other installers to see what they say. It sounds like this should be doable in a more reasonable matter. I'm willing to pay more for a proper quality installation.

In the mean time I will proceed with some energy upgrades (attic insulation, etc) so that I can get away with less panels.

And, only slightly tongue in cheek, they also have big, stuffed bears, but that does not make them child welfare advocates.

Yes ! Keep the cart before the horse and do as much in the way of conservation efforts as possible BEFORE PV rather than after. And, in so doing, if some peddler is using prior usage to estimate system size, reduce the size estimate accordingly and somewhat proportionately to the prior load and you, not the peddler, may estimate.