When most houses are built the mechanical is typically an after thought. If you look at commercial buildings they typically design the building around the Mecha

When most houses are built the mechanical is typically an after thought. If you look at commercial buildings they typically design the building around the Mechanical. I have seen Schools, Grocery Stores, etc, spray-foamed from the outside to prevent the hot/cold air from even entering the building. The basically spray the inner substrate and of course you still have brick ties so you can brick the outside of the building. You just need to leave some extra room on the footings to allow for 3-4 inches of spray-foam. A modern day house when built and finished has approx 2000 ft of linear cracks in it. It is the equivalent of keeping your front door open all year around. There have been test cases done where two homes are built exactly the same but the insulation in one of them is spray-foam. They then do a blown door test and the results speak for themselves. The spray-foamed house has almost no leakage. Here is a couple great sites for anyone in NA to learn more about spray-foam. Demelic is based in Grand Prairie TX and in my opinion makes excellent foam. BASF is another great foam also. https://www.cufca.ca/ https://www.cufca.ca/ http://www.demilec.com/ http://www.demilec.com/