Cement Tile Roof?

[bob-n]

Does anyone here have experience installing on a cement-tile sloped roof? If so, what did you use and what were your experiences? Thank you.

[J.P.M.]

Yea, happens all the time. Real pros know what to do. Larry with a ladder type installers will either screw it up and break a boatload of tiles or try to screw the homeowner by putting comp. shingles under the array while still breaking tiles that are not under the array by acting like hamfooted gorillas and ignorant of necessary technique of how to properly walk on a concrete tile of mission tile roof.

I'm the guy in my HOA responsible for review/approval/job monitoring about 150+ solar arrays, all but two of which are roof mounted. Every roof in my HOA is either flat concrete tile or mission tile. Aside from the usual precautions about when dealing with/walking on such materials with respect to avoiding breakage, installation on such roofs is no different than any other roof.

Some installers try to pull the B.S. of removing the tiles under a rooftop array and substituting composite shingles. When such designs are not approved they've complained like stuck pigs, claiming installing over concrete or mission tiles is impossible. I and 150 other homeowners know better, and that their (the installers) attempts to do what is (IMO as a retired mechanical engineer) poor design practice is done for no other reason than to cheap out and make their job easier at the expense of the home owner getting a ticking bomb when, among other things, low spots and damns at transitions between materials are created and sooner or later start to leak. It's just bad practice that benefits no one except the vendor. BTW, some day, the array will be removed. What then ? Think about it.

FWIW, when my array was installed, I had the lightweight concrete tile on that portion of the roof that was to have the array removed, inspected/repapered, minor repairs done, and the array supports (posts with double flashing) installed by the roofer using the array vendor's drawings and knowledge. The tiles were then reinstalled. The solar vendor then installed the racking and the array. 7+ yrs. in and no leaks.

Installing on what are admittedly fragile materials is not impossible - it just takes a bit more care. Most all the quality solar vendors know this (but still acknowledge that concrete and clay tiles are more of a PITA than comp. shingles) and take it in stride as one of the joys of the job.

See prior posts that just about beat this problem to death before you got here.

[solarix]

TileTrac by ProSolar

[bob-n]

JPM: Can you point me to particularly useful posts? I found a lot of discussion, but may have missed what you meant.

Solarix: Thank you. I'll check out TileTrac.

[J.P.M.]

JPM: Can you point me to particularly useful posts? I found a lot of discussion, but may have missed what you meant.

Solarix: Thank you. I'll check out TileTrac.

Well, not specifically, but most of them occurred over the last 3-4 yrs. or so. Maybe 15 or 20 threads or so, some of them of some length, and I was involved in most or all of them.

The general theme of those threads was someone writing that their vendor wanted to do that and then asking for opinions about whether or not it was a good idea to replace concrete tiles or mission tiles under an array with comp. shingles. The responses were generally of 2 types as is not unusual, for and against. Folks who thought it was a good idea were usually either homeowners who had already had it done that way with no problems (yet), and were trying to bolster their hope that they had not made a mistake. the 2d type tended to be DIY yahoos long on myopic outlooks and short on technical expertise about what can go wrong on a roof and/or those who have never chased a leak on a roof. The other type were generally folks who thought mixing roof systems, particularly in places that were generally inaccessible to even inspection much less servicing such areas as under an array thought it was a bad idea. Those types, at least it seems to me were also those who probably have been on a roof and probably chased a leak or two.

As for experience, after monitoring ~ 150 roof installs on concrete and/or mission tile and seeing a lot of good installs and more than a few installs I wouldn't allow on my home, I'd suggest the solar install be done by competent installers AFTER a thorough inspection and any required servicing of a roof done by professional roofers. Things are improving with respect to coordination of the two trades, but roofers are not solar installers and solar vendors are not roofers. the last few years solar vendors around here have branched into roofing, but most of that seems to be a matter of solar contractors subcontracting out to roofing companies with the roofers changing identifying tee shirts. Nothing wrong with that IMO, but it may wind up costing the homeowner more than separate contracting and saving the homeowner the markup that the solar vendor adds.