Owner builders website showing use of ICF walls and SIP roof ICF walls and SIP roof

Thank you for posting the info.

Did they run the screws 8" o.c. for the roof SIPs? I noticed a small indentation in the panel wherever the SIP screws were run, is that normal?

Posted By Lbear on 06 Jul 2012 01:54 AM
Thank you for posting the info.

Did they run the screws 8" o.c. for the roof SIPs? I noticed a small indentation in the panel wherever the SIP screws were run, is that normal?

Lbear,
depending on wind load, 6" or 8" oc, SIPLD or SIPHD (depending on material being attached to)
screws are used in conjunction with a .... 1-1/2" fender washer or a 1- 1/2" aluminum neo washer. and slightly dimpled to allow for a flush installation of secondary roof finish.

Posted By cmkavala on 06 Jul 2012 06:35 AM

Lbear,

depending on wind load, 6" or 8" oc, SIPLD or SIPHD (depending on material being attached to)
screws are used in conjunction with a .... 1-1/2" fender washer or a 1- 1/2" aluminum neo washer. and slightly dimpled to allow for a flush installation of secondary roof finish.

Do you still recommend taping the joints on the SIPs even though a secondary roof would be applied?

Can one do a 24" overhang with a 12" panel?

Lbear;
the roof tape is only needed if the panel skin is left exposed as the finish, however at a minimum a 15# felt slip sheet is recommended, between the metals if a standing seam roof is used
6" and thicker panels can have a 48" overhang on the eave and a 23" overhang on the rake

So a slip sheet is basically red rosin paper, right? So you would have the steel SIP, then the felt, then the slip sheet, then the standing seam metal roof?

Would 30 LB felt work better?

The slip sheet is there to keep the felt and metal from sticking to one another, right?

Lbear; just the felt 15# min , 30# is more durable, just to keep the 2 metals separate when the standing seam expands/contracts, A peel n stick Ice/water shield is even better, now mandatory on all roofs in Florida as a secondary water barrier.

Beware metal roofing can get hot enough to melt the tar paper and not work as intended. An underlayment designed for high temperatures should be used. Also if an adhearing membrain is not used, each metal SIP roof panel joint should be individually sealed. One cannot rely just on the felt paper to keep the roof water tight.

Posted By JeffD on 07 Jul 2012 06:25 PM
Beware metal roofing can get hot enough to melt the tar paper and not work as intended. An underlayment designed for high temperatures should be used. Also if an adhearing membrain is not used, each metal SIP roof panel joint should be individually sealed. One cannot rely just on the felt paper to keep the roof water tight.

Jeff;
the purpose of the felt is not to waterproof, that is the purpose of the roof. A secondary water barrier membrane can be used in lieu of the felt. Hi-temp for metal, our preference is Polystick MTS

Posted By cmkavala on 07 Jul 2012 07:42 PM


Jeff;
the purpose of the felt is not to waterproof, that is the purpose of the roof. A secondary water barrier membrane can be used in lieu of the felt. Hi-temp for metal, our preference is Polystick MTS

So it would be the steel SIP, then Polystick MTS, then ??????, with finally the standing seam metal roof?

I wonder how hot a steel roof can get in the SouthWest sun? Can it get over 200F in places like Northern Arizona?

Posted By JeffD on 07 Jul 2012 06:25 PM
Beware metal roofing can get hot enough to melt the tar paper ..

Bare steel has relatively low reflectivity and low emissivity, so the temperature of bare metal in the sun can rise to very high temperatures. But if steel is coated with a highly reflective and highly emissive color, then the actual temperature rise of the roofing is relatively insignificant, something on the order of 3 to 5 degrees C above ambient. Whereas asphalt shingles can easily rise to 30 or 40 degrees C above ambient. As long as one does not use bare metal as a roofing material, and takes care to pick a color that will not absorb much solar radiation, and that is also highly emissive, then the heat buildup is non-existent.

Lbear;
Yes, it is SIP - Polystick - Metal roof