[RE-wrenches] Roof flashings on L-feet in high snow load conditions

[Troy Harvey]

Hi all,

We have been doing PV installs for years with L-feet and silicone without problems ever. Even still, gravity flashings seem attractive in shingle roofs, to provide a second level of security, and a more professional install (at least in perception). But the cost of these systems in significant in high snow load areas where we often have L-feet every 2 feet on center, to evenly load the structure below. In todays costs, the feet could cost as much as 33% of the panel value.

I'm wondering what other people are doing in high snow load areas?

Also. I have noticed that there is a flip side to the risks. We have found that unless you have good quality shingles, on a preexisting roof, that sometimes the adhesive sticking the shingles together is stronger than the low quality shingles themselves - adding risk of trying to shoe horn flashing in after the fact. Your experience?

thanks,

Troy Harvey
---------------------
Principal Engineer
Heliocentric
801-453-9434
taharvey at heliocentric.org



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