More and more builders have realized the advantages of leaving stud bays empty and putting all of a home’s insulation outside of the wall and roof sheathing. If done correctly, exterior insulation can help produce a building that is almost airtight, very well insulated, and almost immune to water damage.
The construction method was first developed in the early 1960s by the National Research Council of Canada. In its purest form, the method is known as PERSIST — an acronym for Pressure-Equalized Rain-Screen Insulated Structure Technique.
Here’s how you build a PERSIST house: