Hire roofer who knows solar or solar company who does roofing?

[jytte2]

We plan to get solar soon, but we also need a new roof. Is it better to get a roofer who knows solar or a solar company that does roofing?

• Concrete red curved Spanish tiles
• Would like to put the solar panels on the flat roof of the covered porch due to orientation. Solar company would re-do torchdown. Tilt panels maybe 17 degrees? We're at 33.1 lat, and electric usage is heaviest in summer.

We're considering having a roofing company do the tile section and the solar company do the flat roof re-roof and add solar. If we use two different companies, who should do the work first?

If the flat roof is done first with solar, I'm afraid that the tile roofers might damage the solar equipment.

If the tile roofers are first, then the new tiles have to be lifted for the flat roof torchdown. The tiles on the slanted part of the roof end up just laying on the flat roof when it reaches that part. (At least that's how the original builder left it.)

I'm concerned about where the tiles meet the flat roof so there's no issue as to whose fault it is if there's a leak.

Any suggestions and advice is much appreciated. Thanks.

[J.P.M.]

Before that, a question/two.

The roof flat is probably flat, but is it horizontal ? If horizontal, do you intend to have a horizontal panel orientation on that roof ? If so, know that performance will be less than at some angle to thje horizontal, like 30 deg. or so, depending on azimuth. Also, horizontal panels will need more cleaning. They tend to become shallow sandboxes that reduce production even more.

No good answers on who does the roof. If it was me, I'd hire one company for the entire roof, but choose that company with an ear to what the PV installer thinks. When my array was done, I had needed roof remediation done by an experienced roofer. That roofer also worked with the PV vendor to set the posts per the PV drawings. I coordinated the two vendors work/scheduling and it worked out well with few glitches.

I'd not hire one company for the PV and roof work. My experience, in spite of what vendors may tell you, is that PV installers are not roofers and roofers know nothing of PV. A little involvement got me a good installation and a good roof remediation.

[emartin00]

My suggestion would be to find a roofer and a PV installer who will work together. The PV company can give the roofer drawings of where the mounts need to be, and they will install the mounts while doing the roofing. That way they can make sure any penetrations are properly sealed, and if there were any leak, they can't both try to pin it on the other company.

[Ampster]

My suggestion would be to find a roofer and a PV installer who will work together. The PV company can give the roofer drawings of where the mounts need to be, and they will install the mounts while doing the roofing. That way they can make sure any penetrations are properly sealed, and if there were any leak, they can't both try to pin it on the other company.

I agree. That way you get a single vendor to go after for leaks. Sometimes the solar installer will reduce his bid because he has no liability fo leaks. The perfect sequence would be underlayment, then solar then tiles.

[littleharbor]

I would either have the roofing company lay the first course of torchdown, halfway up, under the bottom courses of tile and tile underlayment or see if the torchdown guys can lay the first course before the tile guys lay their tile. That first course doesn't need to be torched up under the tiles so that wouldn't be an issue for the tile guys.

[J.P.M.]

My suggestion would be to find a roofer and a PV installer who will work together. The PV company can give the roofer drawings of where the mounts need to be, and they will install the mounts while doing the roofing. That way they can make sure any penetrations are properly sealed, and if there were any leak, they can't both try to pin it on the other company.

That's pretty much what I did, but I checked the work and dimensions myself. Trust but verify.

[J.P.M.]

I agree. That way you get a single vendor to go after for leaks. Sometimes the solar installer will reduce his bid because he has no liability fo leaks. The perfect sequence would be underlayment, then solar then tiles.

How do you put the tiles under the array ?

[Ampster]

How do you put the tiles under the array ?

You don't need to put the tiles under the array. The tiles actually dont provide the water proofing the underlayment does. The tiles protect the underlayment so on several installations I have seen the roofers use asphalt shingles or rolled roofing where the solar is going . That protects the underlayment from the sun. It also gives a cleaner look to the installation, still leaves an air gap for cooling and saves money because setting tiles is more labor intensive than composite shingles or rolled roofing.
NB
I reread this thread and it appears that the home has a flat (horizontal) section where he intends to mount the solar panels on angle mounts. If that is the case then the above doesn't matter. My only input on a flat roof would be to consider a membrane system that would give a 25 year life instead of a touchdown 15 year life.

[J.P.M.]

You don't need to put the tiles under the array. The tiles actually dont provide the water proofing the underlayment does. The tiles protect the underlayment so on several installations I have seen the roofers use asphalt shingles or rolled roofing where the solar is going . That protects the underlayment from the sun. It also gives a cleaner look to the installation, still leaves an air gap for cooling and saves money because setting tiles is more labor intensive than composite shingles or rolled roofing.

Yea, I've seen the same thing. The idea is a bad one and gives the owner not one scintilla of benefit over keeping the tiles in place under that array.

If the only benefit of tiles is to protect the underlayment from the sun, then why are tiles also placed under the north side of overhangs ?

If the comp. shingles are tucked up under the array by, say, 6" - 12" or so back from the array edges, with tiles at/under the array edges, how does that present a cleaner look ? An aside - maybe shingles/comp. roofing hidden under an array is also slightly deceptive to future potential buyers of the home ? Caveat Emptor huh ? Real class there.

As long as the array height is the same, the air gap will be unaffected in any meaningful way, as will any heat transfer from the back of the array to the surroundings. That will be definitively true if the tiles are at the edges of the array or inward a bit and under the array by any distance making the entrance/exit dimensions to/from the array unchanged. You can look it up. Don't know where you got that notion from. Pull that one from where the sun don't shine maybe ?

In my conversations with vendors, more than several have involved the weeping and gnashing of teeth, and bitching/whining about tiles staying in place. I've also never observed a vendor offering a price reduction to share in the savings from doing a crappy job and cheaping out. If you think vendors pull this crap for customer benefit or a better job, I've got bridges for sale.

I've also had more than a few vendors swear up/down that arrays can't be placed over tiles. I then point to several such situations within eyesight and easy inspection.

There are many who think the tiles do indeed need to be restored and put back under an array.

Anyone who knows anything about tile roofs knows the tiles are not where the water protection lies. Thanks for the blinding flash of the obvious on that one.
First off, not putting the tiles back most likely started as a cheap out by vendors. It serves no good purpose and only saves the vendor the hassle. It's the lazy way to do it. It's B.S.
If done, the most immediate problem it causes it that it creates interface areas under an array where tiles are supposed to meet (or don't quite meet) composite shingles. Those areas, like most everything else under the array cannot be easily inspected/serviced - if at all. It's creating a possible leak path that doesn't need to be created. Chasing leaks on a roof is bad enough. Chasing one under an array is almost a definition of impossible. Creating an unnecessary leak path under an array is insanity.

Longer term, someday, sooner or later, the array will very likely be removed or modified. What does the owner do about the big, ugly zit where the array was ?

Your post above is another case of you being late to the party. We've hashed this out at least a couple of times or more in the last 5+ years or so. Indeed, there is divergence of opinion that tends toward dichotomy.

One side has mostly vendors and contractors who have only skin in the game but not users interests in mind, or users who were ignorant enough to allow such goings on to be done, and who may want to justify a bad decision to soothe their egos, seem to find no problem with putting very different roofing systems on a single roof section, visible or accessible or otherwise. The second group - those who take a longer and probably more conservative view say put the tiles back and keep one roofing system on one roof section.

Part of their logic is simple: They see no benefit for them to mixed roofing systems - only benefits to the vendor, and many potential problems that can easily be avoided.

Another consideration: HOA's are slowly waking up to the many reasons of the unsoundness of multiple roofing systems on one roof section, seeing no or any real benefit to the owner by using such cheapout techniques, and have changed/amended their CC& R's to disallow such practices. I am aware of at least two. Whether or not building codes catch up and speak to the issue is, at this time, an unanswered question.

[azdave]

I hired a highly rated, locally owned roofing company with 35+ years in the roofing biz and 10+ years in the solar biz. They had the best turn-key price per watt and the buck stops with them if either crew blames the other. No issues 4 year in.

[Ampster]

......The idea is a bad one........m
.

Fifteen years ago I did that to a Spanish tile roof and got compliments from an architectural review committee. My post was simply offering an aesthetic alternative. It may be useful for a few people or it may improve the WAF. You have covered all the reasons why not to do that.
It is also possible this is a moot issue because the OP may be installing the solar panels on the portion of the roof that he described as flat.

[littleharbor]

Has anybody here read that the roof in question is a flat patio cover section that would never have tiles on it anyway?

[Ampster]

Has anybody here read that the roof in question is a flat patio cover section that would never have tiles on it anyway?

Yes, it is in the second and third paragraphs of the initial post.
Here are those paragraphs:
""We're considering having a roofing company do the tile section and the solar company do the flat roof re-roof and add solar. If we use two different companies, who should do the work first?

If the flat roof is done first with solar, I'm afraid that the tile roofers might damage the solar equipment."

I regret I didnt initially understand that since it could have changed the dialog and saved a lot of server storage.

[littleharbor]

"Would like to put the solar panels on the flat roof of the covered porch due to orientation".

Flat roof of the covered porch being the operative words.

[J.P.M.]

Has anybody here read that the roof in question is a flat patio cover section that would never have tiles on it anyway?

I sure did. Note my first post to this thread. My 2d last response to this thread (before this one) dealt with Ampster and his no tiles under array post.