Opinions on sheathing a house
First off Hello, I am a member on a few different forums mainly for my hobbies and have learned a lot from them so I am hoping to learn some more about housing.
My wife and are planning to start a new house this spring and are looking for some advice. Currently we live in our pole shed on the property and love how well I insulted it, we use about 40% less wood in our boiler than most people thought we would.
We are hoping to continue our trend. Anyways it is in western Wi typical 2X6 framing with fibergalss insulation. We priced out spray and it was to much money at a dollar a board foot. So we were talking to some insulation guys and they talked about wrapping the house in rigid insulation, still sheathing the house in osb just adding the insulation in addition. This way you gain the seal of spray foam plus have no thermal bridging from the studs.
I watched some videos on youtube and some companies are doing this, from the videos they showed putting either 1x's or 2x's around the window openings depending on if you go 3/4'' foam or 1.5''. Then you will have to use longer nails to hang the siding. Also some people were using this as there tyvek, they will tape all the seams and caulk the top and bottom peices.
I understand doing this we will need to have a quality air exchanger in the hvac system. Most of the labor we be myself, wife (believe it or not she was a big help in the pole shed) family and friends. So the cost will only be materials.
We really liked the idea of having no thermal bridging. We had a friend out who has a thermal camera and when he shot are exterior wall we couldn't pick out any studs, with an interior temp of about 72degrees and outside about 10. However when we shot the wall separating the living space from the shop we could pick out every stud, the house being 72 and the shop is somewhere around 58-60. I am mainly wondering if I am going to be causing any major problems to the house, especially mold. What else do I need to consider?
Sorry about the long post just wanted to give as much info as I could. Thanks for all the replies.