Insulation on the walls.
For the walls, we installed SilverGlo insulation, an Expanded Polystyrene Foam (EPS) product that is coated with mold-resistant aluminum. This lightweight, rigid, and closed-cell insulation works far better in crawl spaces than over-the-counter batt and foam insulations thats meant for dry attics. This insulation has a closed-cell structure, so there is minimal water absorption and low vapor permanence. It seals in heat and keeps out the cool winter air in the crawl space interior making the house much more energy efficient.