Would you re-paper your roof before install?

[insaneoctane]

My roof is original and 28 years old. I am about to have 24 panels installed. Although I have had an occasional leak repaired, I have been told that it is in good shape. Should I be expecting to have to re-paper as preventive measure? My installation company offers 10 year warranty against leaks for their work (they are also a roofing company)... I could just rely on that... How much savings would I expect to realize by doing it at same time as my install? Would it qualify as part of solar install and thus be eligible for federal 30% tax credit? Lots of questions for anyone with an opinion

[Volusiano]

My roof was about 17 years old when I installed my solar panels. I had the roofer check the condition of my underlayment and he said it's still in good condition and should last another 5-10 years at least. But I went ahead and had them put on a new underlayment layer on top of the old one anyway, but not for the whole house, only under where the panels were installed. This way, that part of the roof should be good for the life of the panels or at least another 20-30 years hopefully. And if I had to re-roof the rest of the house down the line at some point, I don't need to remove the panels because that part's already re-roofed.

My installer said that many of their customers do that and include that cost as part of the "site preparation", which would qualify for the 30% tax credit. If you re-roof the whole house, it may not qualify. But if you re-roof only the portion under that panel specifically for the purpose of preparing the site for installation because the old underlayment is only a few years from needing replacement, then I would think that it should qualify. You should consult your own tax adviser of course for a professional opinion.

My installer was so comfortable about this that they were willing to include this itemized cost in their solar installation invoice as a sub-contracted item, even though I paid their recommended roofer directly. Other "site preparation" stuff that you can probably claim are things like clearing out over-grown trees that may cause shading issues on your solar systems, or stuff like that.

[russ]

I certainly would suggest to re roof the section under the panel area before panel installation - much cheaper and easy to do now.

[J.P.M.]

My roof is original and 28 years old. I am about to have 24 panels installed. Although I have had an occasional leak repaired, I have been told that it is in good shape. Should I be expecting to have to re-paper as preventive measure? My installation company offers 10 year warranty against leaks for their work (they are also a roofing company)... I could just rely on that... How much savings would I expect to realize by doing it at same time as my install? Would it qualify as part of solar install and thus be eligible for federal 30% tax credit? Lots of questions for anyone with an opinion

FWIW, I did. Cost me ~$5K for the additional roof maint., but other non solar roof work included. Separate contractors - roof/solar. I acted as proj. eng./coord. IMO, roof/solar are separate specialties and I treat them as such. I probably paid more, and maybe B.S.'d myself, but I feel better about the quality I got. Pay your money, take your choice kind of thing.

I did not consider my work tax creditable as most/all of it could have been called due to necessary repair, solar or not.

Consider it cheap insurance. You will not be sorry. Chances are at 28 yrs. you'll need work sooner than later. Get it done now and the first time it rains next Dec./Jan. at 2 A.M. and your roof/ceiling section(s) under the panels are dry, you'll have your cheap insurance premium back or at least feel better about having done it. Trust me and others on that one. In the unlikely event of a new leak, you'll have two places to point fingers, and that has its own PITAs and pitfalls, but still a resolution path, and you would have been proactive at the start which usually reduces the probability of problems down the road. No guarantees in life kind of thing.

Also, check w/ your tax advisor on tax credit effects.

[Ian S]

While my foam roof was in good condition, it was about due for recoating with the protective elastomer so I had that done in coordination with the install. The solar panel mounts were installed first then the roofers came and sealed thenm up and recoated the entire roof. Then the PV guys returned to finish the panel installation.

[+3 Golfer]

I looked at it a little differently for my concrete S-tiled 5/12 pitch roof.

My house was also 17 years old when I had my solar added last year. I personally inspected various areas of my roof and the underlayment paper was in excellent shape. In addition, the sheeting in the attic looked like new with no signs of water damage. So, when the installers came they said virtually the same and that there's no reason this roof underlayment needs replaced anytime soon. When I pressed he said when the concrete tiles are replaced. He said you simply need to make sure there are no areas for water ingress (cracked tiles, slipped tiles, flashing, concrete joint caps and so forth). Yes, when there is lack of maintenance, it can lead to expensive roofing repairs. The underlayment acts as a vapor barrier keeping the sheathing "dry". It's not meant to be a substitute for the exposed roofing material. Lastly, being in the Valley with low humidity, and little rain. I'm not worried about my underlayment failing - I guess that means becoming brittle / cracking and offering little protection from moisture dampening the sheathing.

Everyones' risk tolerance is different - cost of repair vs likelihood of underlayment failure and extensive damage. After one has considered "the facts" and if one can't sleep at night during heavy rain storms having a 5, 10, 17, or 28 year old roof, then for peace of mind one might want to replace the underlayment when installing solar panels over a concrete tile roof.

The tax question is an interesting one. I would think that if a roof has a dual purpose, any additional cost to structurally support the panels is okay. But, if the roof simply needs a new roof than I would think at best one might have to apportion the total roof cost to the area under the panels and at worst apportion the previous apportionment between solar and home. I wouldn't take the installer's word. If the IRS rules are not clear, there may be an IRS tax ruling by someone seeking clarification on this. However, IIRC such a ruling only applies to the party seeking the ruling for their specific case but it can serve as a guide to others. Of course, if one doesn't get audited, then it's moot. But again if one can't sleep at night, consult your tax advisor.

[Mike90250]

It's cheap insurance to replace/repair before installing panels. I did.

[Volusiano]

I looked at it a little differently for my concrete S-tiled 5/12 pitch roof.

My house was also 17 years old when I had my solar added last year. I personally inspected various areas of my roof and the underlayment paper was in excellent shape. In addition, the sheeting in the attic looked like new with no signs of water damage. So, when the installers came they said virtually the same and that there's no reason this roof underlayment needs replaced anytime soon. When I pressed he said when the concrete tiles are replaced. He said you simply need to make sure there are no areas for water ingress (cracked tiles, slipped tiles, flashing, concrete joint caps and so forth). Yes, when there is lack of maintenance, it can lead to expensive roofing repairs. The underlayment acts as a vapor barrier keeping the sheathing "dry". It's not meant to be a substitute for the exposed roofing material. Lastly, being in the Valley with low humidity, and little rain. I'm not worried about my underlayment failing - I guess that means becoming brittle / cracking and offering little protection from moisture dampening the sheathing.

Everyones' risk tolerance is different - cost of repair vs likelihood of underlayment failure and extensive damage. After one has considered "the facts" and if one can't sleep at night during heavy rain storms having a 5, 10, 17, or 28 year old roof, then for peace of mind one might want to replace the underlayment when installing solar panels over a concrete tile roof.

I've heard that where as concrete tiles can last a long as 50 years, underlayment life varies greatly depending on the type and quality of the underlayment material as well as the quality of the installation. But for sure they don't last forever. I've heard of underlayment life anywhere from 10 to 15 to 20 to 30 years, depending on whom you talk to.

When I had a roof leak shortly before they installed my solar system, I asked the roofer who looked at the leak to check and see what kind of shape my underlayment was in the area where the panels will go on. He said they still look pretty good, maybe good for another 10-15 years. But he also noticed that the ridge line on my roof does not have any so-lite plastic seal to keep water from a heavy rain to seep inside. He said at the time of my home construction 17 years ago, it wasn't required by code, but now it's required by code. He said with this seal at the ridge lines, it'll help the underlayment last longer because there'd be less water seeping in through the openings at the ridge line when there's heavy rain that blows sideway.

He wasn't trying to upsell me to install new underlayment under the solar panels. He said that the original underlayment will last for several more years so I can just leave it alone and put the panels on top if I want. But on the other hand, I shouldn't expect it to last forever, either. At some point, I'm going to have to replace it, just don't know when. But it's been 17 years.

He left just quoting me for the leak repair and the sol-it install (I decided to go for it since it's now code and I want to be up to code). But in the end, I decided to have him put on a new 2-ply #40 underlayment on top of my original underlayment, but only in the area where the panels will go on. He also told me that the original underlayment was just a 1-ply material. No surprise there since it makes sense that the builder had no incentive to go with anything but the cheapest material to keep the cost down, especially on something that's hidden out of sight.

[+3 Golfer]

Yes, my new home built in 2006 had a plastic piece at the top of the roof. That is an area of concern as on my current home I have 3 small hip roof areas where at the peaks where the roof ones meet, roof tile are cut at angles and just laid in place with the cap tiles over top. The fit was terrible and it looked that wind could easily blow water back under the cap tile. I used Henrys roof sealant to hold many of these pieces in place and cut the proper angles on aluminum flashing where the roof lines met and cemented them in place.

I also had a poorly applied vertical flashing / drain for runoff of maybe a 200 sq.ft. roof area. S- tile was placed over top of this drain and had smashed the 1" lip on the drain channel down. Tree debris eventually clogged the channel and water spewed onto the underpayment about 3 feet from the roof edge. When we had our first heavy rain a few months after we moved in, I walked around the house looking for issues and found water running pretty much everywhere but the drain. I pulled up 3 rows of tile and had to replace about a 4x5 section of dry rotted plywood. The trusses were fine

So needless to say I inspected all flashing and drain areas and cleaned them out. I also had about a 20' Palo Verde taken out which was the source for the debris and also would have shaded my panels. I now feel very good about the shape of my roof. And now with panels, the life of the underlayment under the panels probably doubled!!!

[insaneoctane]

In my case, the vast majority- let's say all, of my main south-facing roof will be covered with solar panels. Would I expect a price break from my solar installer (who happens to be a roofing company that later got into solar) to do a re-paper (or paper overlay) while they are installing the solar tie ins? I don't really have a full appreciation for how much of the roof comes up during the tie in process. What kind of "discount" would you suggest I be looking for (if any)? If it weren't a great discount, I'd probably have the local roofer who's fixed my leaks in the past do it prior to the install.

[Volusiano]

In my case, the vast majority- let's say all, of my main south-facing roof will be covered with solar panels. Would I expect a price break from my solar installer (who happens to be a roofing company that later got into solar) to do a re-paper (or paper overlay) while they are installing the solar tie ins? I don't really have a full appreciation for how much of the roof comes up during the tie in process. What kind of "discount" would you suggest I be looking for (if any)? If it weren't a great discount, I'd probably have the local roofer who's fixed my leaks in the past do it prior to the install.

I wouldn't think they would need to remove that many tiles for the tie in. Probably around the area where the posts are going to be screwed in to the trusses, that's all.

Whether you can expect a discount or not, it's irrelevant because if they give you a discount but still come up higher than your local roofer, then you wouldn't want to go with them anyway.

[+3 Golfer]

In my case, the vast majority- let's say all, of my main south-facing roof will be covered with solar panels. Would I expect a price break from my solar installer (who happens to be a roofing company that later got into solar) to do a re-paper (or paper overlay) while they are installing the solar tie ins? I don't really have a full appreciation for how much of the roof comes up during the tie in process. What kind of "discount" would you suggest I be looking for (if any)? If it weren't a great discount, I'd probably have the local roofer who's fixed my leaks in the past do it prior to the install.

On my previous solar installation, a roofing 2-man crew removed all the tile that would be under the panels where the posts would be mounted. That amounts to about 9 rows of tile for 2 rows of panels. I asked why they removed all tiles and they said it was much faster laying out, finding the trusses, and installing posts than removing likely 4 tile around each post location. Who knows but that's how they did it. But it really doesn't take long for them to remove and replace 9 rows of tile. The labor is in removing and replacing the old battens and underlayment. On my current solar installation, the installers removed just the tile around where the posts would be placed. But since it really doesn't take long for roofers to remove and replace rows of tile, I really doubt there would be much of a discount just from the savings for removing and replacing all tile under the panels.

Also, here's a quote from a large roofing contractor on cement tile and underlayment. "The life expectancy for a concrete tile roof is marketed as a 50 year roof. However, the underlayment and batten system, even if good material and the proper installation procedure was used, will not last that long and will have to be replaced generally around 30 to 40 years." So, since my underlayment was in great shape after 17 years, I chose not to do it. And again on their website: "Tile roofs are prone to moisture penetration from wind driven rain or snow more than any other type of roofing product. That is why the underlayment, batten system, and flashing and how they are installed is so very important and is the key to how long a tile roof lasts." Preventing water from reaching the underlayment is the issue not the life of the underlayment per se.

Given your roof is 28 years old (and you had a leak), I'd consider getting the entire roof redone and bring it up to today's standards.

[Volusiano]

Also, here's a quote from a large roofing contractor on cement tile and underlayment. "The life expectancy for a concrete tile roof is marketed as a 50 year roof. However, the underlayment and batten system, even if good material and the proper installation procedure was used, will not last that long and will have to be replaced generally around 30 to 40 years."

Here's the subsequent sentence to that same quote: "The life expectancy for a concrete tile roof is marketed as a 50 year roof. However, the underlayment and batten system, even if good material and the proper installation procedure was used, will not last that long and will have to be replaced generally around 30 to 40 years. Many tile roof underlayments and battens must be replaced much sooner because of the inferior materials and installation procedures used - sometimes within the first five to eight years".

I just want to point that out that while I agree that preventing water from reaching the underlayment is key to its preservation, it is not the only overriding factor. If the material used is inferior, even if they never get wet, they can still wear out due to exposure to heat and wind and the elements. If it's inferior material, it probably won't last you 30-40 years.

[+3 Golfer]

Here's the subsequent sentence to that same quote: "The life expectancy for a concrete tile roof is marketed as a 50 year roof. However, the underlayment and batten system, even if good material and the proper installation procedure was used, will not last that long and will have to be replaced generally around 30 to 40 years. Many tile roof underlayments and battens must be replaced much sooner because of the inferior materials and installation procedures used - sometimes within the first five to eight years".

I just want to point that out that while I agree that preventing water from reaching the underlayment is key to its preservation, it is not the only overriding factor. If the material used is inferior, even if they never get wet, they can still wear out due to exposure to heat and wind and the elements. If it's inferior material, it probably won't last you 30-40 years.

Absolutely, if upon inspection, the underlayment / installation is of poor quality, then replace. The points of my posts are to disabuse the apparent "groupthink" (4 out of 4 replaced / suggested replacement) in this thread that all underlayment has a short life and thus it makes sense to replace it when solar panels are put on.

As I stated previously my underlayment (and apparently yours) is in excellent shape. It has considerable life in it maybe up to 40 years or longer as the roofer said (when inspecting my 17 year roof when I had a 430 square foot patio cover added that tied into the existing roof line in early 2013): it probably won't need replaced until you replace the tile. He stressed the importance of maintaining one's roof (of course they suggested periodic inspections by roofers) and you won't have leaks. I'll bet the vast majority of homeowners never go on their roof and look around and never had an a roofer on the roof until it leaked.

[Volusiano]

I'll bet the vast majority of homeowners never go on their roof and look around and never had an a roofer on the roof until it leaked.

I think you're right here. The key is regular inspection to detect and fix issues before it becomes a problem, and almost nobody does that. I'm guilty of that as well. Never bothered with the roof until it had a leak 17 years later after it was built. Then roofer noticed issues while assessing the source of the leak such as a couple of dozen cracked tiles and lack of sol-it plastic cover on the ridgeline.

Neighbor saw them working on my roof and asked my roofer come over to look at a leak he had. I'm like, wow dude, what if my roofer hasn't been spotted by you, are you just going to wait until the leak gets worse before calling a roofer? Turned out some of his tiles got shifted out of position (don't know how, maybe by strong wind gusts), so his underlayment got exposed to the element and wore out prematurely.