Although the rim joist is frequently an afterthought once a house is built, an insulated rim joist can go a long way toward helping to reduce energy bills. Isaac Savage, president of Home Energy Partners in Asheville, N.C., details his technique for insulating a rim joist. Forgoing fiberglass batts, which can permit airflow, Isaac uses spray-foam insulation to fill all gaps, holes, and joints. The article includes a list of spray-foam sources.
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