In those days common building practice was to insulate the floor above the crawl space and to leave the crawl space s wall vents open so any moisture buildup would vent to the outside a.
Insulation crawl space floor joists.
Cover the walls with insulation from the sill plate to the plastic covered dirt floor.
The sill plate is the first piece of framing lumber and it runs on top of the crawl space wall.
When the basement or crawl space has vents installed insulating joist bays.
Where winter temperatures are extreme opt for insulating the walls and sealing off the crawl space entirely.
In moderate or dry climates without the threat of sustained subfreezing temperatures insulation between floor joists makes sense.
Fiberglass insulation batts or rolls are the most economical and easiest diy choice for insulating between the floor joist in a crawl space.
Department of energy recommends r 11 3 insulation under floors in warm climates and an r 25 6 to 8 in cold climates.
Floor insulation for moderate climes popular reads.
It is important to secure insulation and cover it with a vapor barrier in order to prevent moisture and the mold that often follows close behind.