There are many choices to make regarding choosing a building envelope, starting with a basement foundation or a slab-on-grade, and a multitude of different building envelopes. Your building envelope or 'wall system' encompasses every part of your wall from inside to out.

There is not one ideal building envelope; that depends on the individual, as well as the climate  where you choose to build. Just as the outfits we choose to wear vary by location, the optimum building envelope will vary as well.

First you’ll need to prioritize and find a balance between budget, home size and performance. If you have a minimum space requirement and maximum budget, you will have limitations as to the quality and performance you can afford. 

If you have a maximum budget and want a high performance home, then you might have to sacrifice some square footage. A flexible design allows you to go this route and expand in the future if necessary.

Your building envelope ideally should be viewed in the same way you would any financial investment, invest money now to get more back later. A better-insulated home might cost more up front, but once it’s paid for you’ll see a net savings from lower operational costs. A better-built home will also be more comfortable, healthier and more durable. Consequently it last longer and have greater value far into the future. 

Keep in mind that the monthly savings on utilities with a more efficient home can at times match or exceed the higher monthly mortgage rate you may pay for choosing a better home, so in some cases there is no payback period at all, you are simply diverting financial resources. Money that would have been spent on heating and cooling is instead invested in paying down a mortgage.