How to Insulate a Cement Slab
- 1). Roll out the vapor barrier across the entire floor. Cover all edges and corners in particular.
- 2). Lay the 2-by-3 lumber across the floor on top of the vapor barrier in lines spaced evenly 16 inches apart on center. The entire perimeter of the slab should have lumber running along it.
- 3). Nail the lumber to the floor using the framing nailer. The power of the nailer will penetrate the concrete slab without an issue.
- 4). Roll out the insulation between the newly nailed lumber. Pack the insulation into the spaces between the lumber.
- 5). Cover the subfloor and insulation with the sheets of plywood, nailing each down to the subfloor using the framing nailer.
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