No, my rafters are generally continuous and not overlapped or staggered. There is some sub-structure framing that causes a substantial change in rafter pattern in a couple of spots. I can post some pictures for those interested.
Nope, no roofer's cement or other sealant on these nails. 100% of protection for these penetrations is provided by the tile layer above.
I was cautious my first few trips up a month or two ago to take measurements for the permit application, using the techniques you've described here, but at this point I just walk freely (but not stupidly). I keep looking for a crack, but the next one I make will be the first one.
I think my roof will be a good test for how long it takes for that condensation to do damage here. Thousands of holes protected only by the nail filling them. Clearly, the roof is better protected with paper than without (I'm not questioning that at all). It is just that it is hard to look at all those tile nails and think of the roof as having been impervious until I came along with my lag screws and PV mounts.
No holes are visible when the concrete tiles are installed. With the tile removed, I bibbed with paper over the few new nails I put in when I was first following the instructions after step 5, but I have stopped putting in new nail holes to avoid this problem completely. Their function isn't so clear... there is nowhere for the aluminum flashing to go, even if the sealant that adheres it to the paper eventually lets go. Maybe the nails are needed for a steeper roof with more clearance between the deck and the tile? Here is the pic from the manual that shows them. nails.JPG
It is a weird use of screws... the screwhead isn't the functional end... the tip is. The quickhook mates with the mounting base like a slide and gib. The screw works sort of like a set screw in that once you drive the screw in far enough, the tip pushes on the base and forces the hook up against the gib, securing it. In other words, if the head were tightened against its mating face like a normal fastener, the screw wouldn't be doing anything at all (for that matter, the mating face in this case isn't even flat). A screw that is twice as long would be just as functional (but would interfere with the flashing). The picture from the instructions below, hopefully I'm describing this clearly enough. I'm sure they aren't supposed to shear, and the instructions warn against using an impact gun, but I'd rather have them too tight than not tight enough, you know? Medium torque on my drill doesn't drive them at all. screw.JPG
From a common sense perspective, the concrete tile nail holes worry me much more than what I'm doing with these mounts, but I don't think I'm going to lose sleep over any of it. I'll definitely post some more pictures soon, but I understand better now why Solarix has taken the position he has on the suitability of some of Quickmount PV's competitors.
Edit: In any case, J.P.M., thanks for the comments.
Nope, no roofer's cement or other sealant on these nails. 100% of protection for these penetrations is provided by the tile layer above.
I was cautious my first few trips up a month or two ago to take measurements for the permit application, using the techniques you've described here, but at this point I just walk freely (but not stupidly). I keep looking for a crack, but the next one I make will be the first one.
I think my roof will be a good test for how long it takes for that condensation to do damage here. Thousands of holes protected only by the nail filling them. Clearly, the roof is better protected with paper than without (I'm not questioning that at all). It is just that it is hard to look at all those tile nails and think of the roof as having been impervious until I came along with my lag screws and PV mounts.
No holes are visible when the concrete tiles are installed. With the tile removed, I bibbed with paper over the few new nails I put in when I was first following the instructions after step 5, but I have stopped putting in new nail holes to avoid this problem completely. Their function isn't so clear... there is nowhere for the aluminum flashing to go, even if the sealant that adheres it to the paper eventually lets go. Maybe the nails are needed for a steeper roof with more clearance between the deck and the tile? Here is the pic from the manual that shows them. nails.JPG
It is a weird use of screws... the screwhead isn't the functional end... the tip is. The quickhook mates with the mounting base like a slide and gib. The screw works sort of like a set screw in that once you drive the screw in far enough, the tip pushes on the base and forces the hook up against the gib, securing it. In other words, if the head were tightened against its mating face like a normal fastener, the screw wouldn't be doing anything at all (for that matter, the mating face in this case isn't even flat). A screw that is twice as long would be just as functional (but would interfere with the flashing). The picture from the instructions below, hopefully I'm describing this clearly enough. I'm sure they aren't supposed to shear, and the instructions warn against using an impact gun, but I'd rather have them too tight than not tight enough, you know? Medium torque on my drill doesn't drive them at all. screw.JPG
From a common sense perspective, the concrete tile nail holes worry me much more than what I'm doing with these mounts, but I don't think I'm going to lose sleep over any of it. I'll definitely post some more pictures soon, but I understand better now why Solarix has taken the position he has on the suitability of some of Quickmount PV's competitors.
Edit: In any case, J.P.M., thanks for the comments.
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