Crawl spaces
How to insulate crawlspaces properly as part of renovating an older home
...to the walls behind the studs and into the cavities, you can leave enough room to do any wiring if required.
Spray foam insulating basement walls © Bala Structures
The foam needs to then be covered with drywall as fire protection, which can be attached to the stud wall. No vapour barrier is required in addition to sp...