New Home - Insulation

[colsbuild]

Hi,

I am building a new home in Ohio and have the following concern with my builder on Insulation.

My builder is insulating some parts of the house with an R3 foam insulation and very minimal. Almost the house is getting completed using the OSB boards. When I asked, they mentioned that foam boards are cheaper than OSBs and OSBs are good on insulation. Is this a good thing or a bad thing ? How much effective will a R3 foam board be Vs. OSB ?

Please let me know.

[Rich]

I think they are using the foam board as the exterior sheathing then? There are many insulated exterior sheathing products out there now - do you have a name of it? And they will also insulate the wall cavity itself? If they don't insulate the wall cavity it won't pass inspection anyway. Your building department will set a minimum R rating for walls and ceilings - typically R19 and R30 respectively. Some areas are beginning to go more than that even.

[colsbuild]

Yes, that is a Styrofoam for the exterior sheathing.

My question is, is it a problem if they just do the OSBs without the foam material all around the house ? I am worried about the utilities during winter if there is no insulation on the exterior.

[Rich]

Yes - it's acceptable. As long as the exterior is properly flashed and sided, and the interior walls have the correct amount of insulation. What material is your wall framing - 2x4 or 2x6? If they are 2x4 I would suggest spending a little extra money to use spray foam insulation... if they are 2x6 you can save some money by using batt insulation (R19).