It happens all the time here with 5V metal roofs. Roofing contractors typically go around and swap all of the backed out screws with larger ones and that pushes out the replacement timeframe.
I believe it is due to over-torque, creating a weak connection to the sheathing after thermal cycling for years. I landed on this conclusion because it is rarely all screws on a roof, or isolated to particular sections of the roof. It's random, suggesting that some screws may be tightened too much. That's just an anecdotal read, nothing scientific. Jason Szumlanski Principal Solar Designer | Florida Solar Design Group NABCEP Certified Solar Professional (PVIP) Florida State Certified Solar Contractor CVC56956 Florida Certified Electrical Contractor EC13013208 On Fri, Sep 25, 2026 at 2:36 PM William Miller <[email protected]> wrote: > Colleagues: > > > > I have a long-time PV client with a metal roof. This is the type of > roofing with trapezoidal ridges every 12 inches. Over the years we have > installed three phases of solar on this roofing. We original caulked DPW > feet onto the roof with fasteners into the framing. Later we used DPW > EZ-feet with the included butyl tape. > > > > The client informed me that have had minor roof leaks due to failure of > the fasteners. To quote: “Unfortunately I chose the less expensive version > of the roofing, way back then. It has “exposed fasteners”, the screws and > washers are working loose.” (No one has claimed our attachments are > leaking but you can bet I will be looking at them closely.) > > > > This is the first time I have ever heard of this type of failure. Have > any of you experienced this? Can you offer any explanation on what caused > this and how you dealt with it? I would be very grateful. > > > > It seems to me that replacing the fasteners would invite stripping of the > threading into the wood sheeting. > > > > Thanks in advance, > > > > William > > > > William Miller > > Miller Solar > > www.millersolar.com > > CA License C-10 77398 > > > _______________________________________________ > List sponsored by Redwood Alliance > > Pay optional member dues here: http://re-wrenches.org > > List Address: [email protected] > > Change listserver email address & settings: > > https://lists.re-wrenches.org/mailman/options/re-wrenches_lists.re-wrenches.org/ > > There are two list archives for searching. When one doesn't work, try the > other: > https://www.mail-archive.com/[email protected]/ > https://lists.re-wrenches.org/pipermail/re-wrenches_lists.re-wrenches.org/ > > List rules & etiquette: > http://www.re-wrenches.org/etiquette.htm > > Check out or update participant bios: > http://www.members.re-wrenches.org >
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