Install rigid foam while the wall is lying down
user-1112892055
| Posted in Energy Efficiency and Durability on
Has anyone tried installing the rigid foam EPS or XPS while the wall is on the floor deck and then installing the plywood over the foam overlapping foam seams before lifting the wall into place ?
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Zip R Panels by Huber provide that, however they are NOT designed to provide combined wall shear and uplift force mitigation. You need to have an engineer and bldg official to approve application.
APA, the American Plywood Asoc. has an approval on panel siding with 1" foam. Check them out.
If you try to do that on your own, you need to have an Engineer and maybe the bldg official approve your application.
IMO, that is the wrong wall assembly because the foam should be on the outside of the structural sheathing.
The Zip R panels are rated for structural lateral loads. The design criteria can be found in the ICC report. I don't thing they can be used with the conventional design provisions of the IRC. The structure would need to be engineered. With the foam spacing the OSB away from the studs it is substantially lower in shear capacity than if the OSB was applied directly to the studs.
You may need to worry about sheer strength if you live in an area prone to earthquakes, otherwise you are fine on a structural basis. Houses how so much going on that helps to support other components. Having a bit of space between the studs and the sheathing is the least of your worries. Structure is about carrying weight and making sure it's transfered onto your foundation. Your house will not collaspe to the side unless it is built on a 45 degree angle.
Zip-R fastening requirements found on page 5 of this PDF.
http://www.huberwood.com/assets/user/library/ZS_R-Sheathing_Installation_Manual-(R3-12)v21.pdf
If you live in an area where earthquakes (natural or man-made), tornadoes, or hurricanes are common, you have wall shear and uplift forces to deal with, and you should consult with an engineer.
Several municipalities in oil states are considering local amendments to codes due to fracking earthquakes. Same is happening in several states after recent tornadoes in the Midwest and South.
Also, the 2015 IRC increased wind load design for most folks.
I stand corrected -the R-zip panels can be used with the IRC design method under the WSP bracing method.
This is not in an earthquake zone. why not use steel let-in bracing on the interior for anti-racking ?
or I could install plywood on the corners before the foam then 1.5" foam on the corners and 2" everywhere else then the OSB over it all. wall might be heavy but this is a small house.
Do a search for "extended plate and beam system" Here is some of the work being done by Build America
https://www.nrel.gov/docs/fy16osti/65326.pdf
https://www.nrel.gov/docs/fy15osti/64163.pdf
https://energy.gov/eere/buildings/downloads/constructible-and-durable-high-performance-walls-system-extended-plate-and