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TOPIC: Product Selection

Raised clips with standing seam

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Hi In considering ATAS Dutch Seam style standing seam on 4:12 gable roof in Florida, non-coastal: Advantages/ disadvantages to using raised clips or shims for 1/4 inch space above sheathing 1. Is condensation under the metal a concern? 2. Worthwhile effort for venting and eliminating direct contact heat conduction? 3. Could some kind of reflective underlayment be used to advantage? 4. Disadvantage for high wind (HVHZ) performance? 5. Is walkability a concern for narrow pitch (say 11 inches)? I’m still conflicted on underlayment. Peel and stick the whole roof or switch to synthetic for the field area? I don’t mind the extra cost if the P&S will hold up but I have my doubts. Thanks for your help (sorry if these questions have already been addressed and I couldn't find them).
Merrick Endres

11/5/2015
1. Not if you have a proper vapor barrier across the roof deck (synthetic underlayment). 2. Above deck venting is great and especially in a climate like FL. 3. Yes. 4. Not a huge issue as long as it is fastened and vented on the top and bottom. Pressure should be equalized in that case. 5. You don't want to step in the open fields but if you are worried about it, you can install some foam strips in the middle to help support or another wood member. No need to go Peel and Stick if the underlayment is done properly. Eric Novotny
Eric Novotny
An informed customer is the Best Customer!

11/5/2015
Hi Eric, thanks for your quick reply. 1. I'm wondering about frost or dew forming under the panel that might result in water ending up being caught in the panel hem and causing corrosion. 2 & 3. Good to hear; seems like a good idea to me. 5. How do you walk on a narrow, raised panel installation? I've experimented with a 15 inch panel that seemed flexible enough to step in the field. I need to clean out a chimney occasionally. Does peel and stick underlayment hold up as the sheathing expands and contracts and wiggles around over the years? New question: attached is my thought for installing the eave trim. Am I on the right track? Thanks again, have a good weekend.
Merrick Endres

11/6/2015
Merrick, 1. Any moisture formation there would be from the ambient air condensation and should not be of any significance. There is no moisture coming from the attic at that point with a proper underlayment and solid roof deck. 2&3. I agree. Above deck venting is great in FL and even in cooler areas to prevent snow melting. 5. Carefully. If you run a wide field, you should be walking on the seams are a general guideline anyway. I don't see any issues with the peel and stick, its just not needed. Looks good on the details as well. Eric Novotny
Eric Novotny
An informed customer is the Best Customer!

11/6/2015
Thanks Eric. I'm having trouble warming up to the thought of walking on the seams. Assuming they're strong enough, isn't wearing the small paint area a concern? What kind of foam supports could be used? About how big? Thanks again; this is a great resource.
Merrick Endres

11/9/2015
Foam strips would be the same thickness as the air space gap and if you have a 21" panel, I would rip the foam down to about 2" wide and put 3 of them per open field. At that point you would have 4" gap between the supports. Should make walking in the field fine at that point. Eric Novotny
Eric Novotny
An informed customer is the Best Customer!

11/9/2015
Something springy like carpet foam or stiffer like urethane insulation foam?
Merrick Endres

11/9/2015
Rigid foam for certain. Eric Novotny
Eric Novotny
An informed customer is the Best Customer!

11/9/2015
Roger that- thank you much. Merrick
Merrick Endres

11/9/2015

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