Hunter panels on sidewalls
Additional thought here… should I add another inch of foam prior to installation to stagger the seams? The wall assembly, even using fiberglass in the wall cavities, will be R-30+ AS IS. The roof assembly, assuming 5 inches of foam on the underside of the roof deck, will be around R-50.
Any advice would be appreciated.
Hey folks,
First post here. Getting ready to gut renovate a 1960’s ranch and create a faux Craftsman in North Carolina (zone 3a). I scored a deal on some Hunter ventilated panels http://www.hpanels.com/2009/pages/pdfs/Lit_Prod_Color/Cool-Vent.pdf with 3″ of poly iso insulation that I plan to skin the exterior of the building with. The exterior walls are 2×4, the new roof will be trusses. I am planning to use spray foam on the walls and underneath the roof deck. A couple of questions:
1) The manufacturer lists this product for roof decks, not sidewall applications. other than making sure there is a bug screen at the bottom, can anyone see a reason it won’t work in a sidewall application? I believe the exterior siding will be vinyl.
2) Open or closed cell foam on the interior? I know open cell will allow the wall to breathe better, but I love how the extra rigidity that closed cell foam brings.
3) I’m assuming that there will be no problem using Typar/Tyvek in this application. Am I mistaken here?
Thanks, reno starts in a month, hope to be “in” by Christmas, provided other projects don’t get in the way.
Thanks
Bill
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Replies
Your very best advice would be to get a set of plans from BSC. You are on the verge of overkill and may end up trapping moisture in OSB, etc.
Hunter Panels on the sidewalls would need bug screen and then use cellulose or Spyder in the walls, An advisor on GBA likes Spyder in your climate. Maybe Chandler will chime in or would draw up a plan for a fee for you.
Hint: Foam insulates very well. Leaks between foam sections also rot very very well!! And air leaks between panels can lower the R value of panel foam to Zip, nada, zero.
Two blogs to start with for reading into...
https://www.greenbuildingadvisor.com/blogs/dept/qa-spotlight/choosing-cost-effective-wall-system
https://www.greenbuildingadvisor.com/blogs/dept/musings/joe-lstiburek-discusses-basement-insulation-and-vapor-retarders
The Hunter panels will work fine but you have to detail them right as AJ recommends and you already know. A few questions, you say it's a gut renovation. how clean are you stripping the walls and how are you air sealing them? Are we going over board sheathing and house wrap with the foam or direct to the siding or studs? How far from Saxapahaw NC are you located? Got hurricane issues? What are you using for windows and how do you plan to set them with the exterior foam?
Michael,
I'm planning on taking the house down to bare studs on the inside and to the wall sheathing on the outside. I haven't verified the wall sheathing yet, but believe it to be plywood given the age of the house and the roof sheathing. The panels will be applied over the existing sheathing after I tape the seams. I'm not quite clear where the house wrap should go, seems with the vented panels it may need to go on before the foam. Windows are likely to be Ply Gem aluminum clad, double pane with low e glass, but we're still looking. I'm planning to set plywood bucks to extend the windows.
I'm located in Southern Pines, about 60 miles from you according to Google. No hurricane issues.