I am investigating building my own home in the next few years and I have become interested in double/staggered stud construction (8″ sill and header) with sprayed in insulation to make a superinsulated outside wall.
Does anyone know of any disadvantages of this method in comparsion to stndard 2×6 construction on construction with SIPS?
I am looking for a good book on this topic. I will be doing the framing myself so labor is not that much of a factor…
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fwiw,
my plan to build my next house is 2x6 steel stud framing with a type of insulation that is sprayed in similar to the expandable foam. I want thick walls for deep window sills.
remodeler
Labor will be much of a factor. If you think you can raise a 2x8 wall all alone or place SIPs all alone, you have just begun to learn. It's a good thing you are getting a head start.
A 2x4 wall filled with sprayed faom is about as good as it needs to be. That gives you R-28. If you use 2x6, it gets way better. With SIPs, you need to definitely plan on air/heat exchange system adding to cost but it is best way to go for high insulation because it overcomes the thrermal bridging which is probably why you are enchanted with the idea of the double stagger stud wall.
I regularly check on a house that I built facing the cold NW wind on a beach. It has urethene foam in 2x4 walls and you can't tell that a storm is blowing. It is supposedly good on fuel too. Everytime I walk in there, I pat myself on the back.
Excellence is its own reward!
hey... what happened to my mooney wall ? i can't find that thread..
2x4 16" OC... with 2x3 horizontal interior .. dens-pak cellulose.. all electric devices nailed to the 2x3...
5 real inches of cellulose... true R-19... very small thermal breaks... lots of nailing for sheet rock / blueboard & trimMike Smith Rhode Island : Design / Build / Repair / Restore
Thanks for the advice!
I was wondering if I was over thinking this. the only reason I do not want to use SIPS, is that although I am convinced that they are a good construction option, there are few houses around here that are built this way and I am not sure that potential buyers down the road will think they are so great. I am just not willing to risk such a big investment!
Does thermal bridging really make that much of a difference?
I am using the SIPS on the roof however. It is a story and half bungalow with dormers front and back and I can get them from the company prebuilt and crane them in place.
Have you ever seen the SIPS put in with a "cold roof" layer of decking over them? The no ventalation part is what I am worried about
the higher the surrounding R-value , the more effect thermal bridging has on the assembly... thermographs give great graphical displays of thermal bridging..
make sure of your details with SIPs... one of teh primary factors in the roof failures of those alaskan SIPs roofs was failure to seal all of the joints with expanding foam ..
the joints became conduits for moisture to get in and condense... rotting out the entire roofsMike Smith Rhode Island : Design / Build / Repair / Restore