I’ve been told that it is possible to add insulation underneath vinyl siding. Is there a limit to the amount that you can add?
I am siding a house that is located in a very warm area during summers. Assuming that I’m OK with the aesthetics, is it possible for me to add say 4″ foam insulation underneath my new siding?
If so, how would that be done?
Thanks.
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Replies
Use long nails.
If you are going to use 4inches of rigid on the outside, plan on a lot of time and extra labor furring out your windows/doors and having a potentially different look along your eave where trim and siding come together...Isn't 4 inches overkill? I would think that 1 and half inches would be too much, especially on an already insulated wall....
Towle,We have temperatures in the 110-115 degree range during summer. That is the issue I am trying to address.About the 'thick look,' we are OK with that. At one time we had planned a straw bale house on this site and found the thick walls attractive. I believe that the thick insulation would only be on the south side of the house. The other sides would be insulated but not so heavily.Unfortunately I was a bit spoiled with this straw bale project. Our energy analysis showed that we would need to add zero auxiliary heat or cooling because of the insulative factors with that approach. I would like to achieve a similar effect going this route, if at all possible.Thanks for the feedback.Martin
Well, I would think that 4 in of rigid is a sound choice when you are considering the r-value. You are certainly going to need long nails and possibly sleepers spaced to the vinyl siding specs for nailing. There may be a capped nail that you could hand-bang to attach the rigid to the house....capped nails have been called for to attach a new synthetic roof underlayment to roof decks and the cap tends to be green or something. Best wishes on the project....
Maybe 5-6" long screws with washers that they use to attach 4" foam on flat roofs?
It has been a long time since I have seen them used, but they must still be out there somwhere. The screws are flat head philips with a 2" washer aleady attached and dimpled with a counter sink. The ones I picked up were used to install foam on the roof of a Sears building. The foam was then covered with EPDM and ballasted with pea gravel. Maybe Piffen will see this and remember using them at some time durring his roofing career.
The OP will still need some kind of furring strips over the foam as a nailing surface for his siding. I have used 2 1/2" alum. nails for a vinyl siding install over old celotex fake brick. The property owner didn't want the extra expense that furring would have added to the job. I wrote a disclaimer in the contract for wind damage because I felt that the longer nails were a weak link. I felt it was like hanging a picture on the end of long nail only driven 3/4" into a stud. He never lost any siding that I know of, but it just didn't seem correct when I installed it.
Dave
this stuff is supposedly good.
http://www.alcoa.com/alcoahomes/products/SSF/ByStyleResults.aspx?styleId=816&productCategory=1
oops! i didn't totally read your thread.