Rigid Foam Insulation For 2x4 Walls

Your plan to use 4 of closed cell rigid foam as continuous exterior insulation is sound and will get your r 20 or thereabouts without any insulation in the stud cavities so adding rockwool to the stud cavities will get you well above your r 20 target.

Rigid foam insulation for 2x4 walls.

Before switching to spray foam insulation tom used to use polyisocyanurate panels that way he would build a 2x4 wall insulate between the studs with batting paper face removed then cover the whole thing with foil faced panels and seal them with foil tape before putting up wall board. Polyurethane rigid foam insulation is expensive compared to fiberglass batts. Keep in mind that any interior rigid insulating panel must be covered by a barrier. The correct method of using rigid foam is to run continuous 4 foot by 8 foot sheets of the foam across the concrete basement wall making the rigid foam the de facto wall.

It is delivered in 8 foot long bundles and each rigid foam batt is sized to fit in between the studs with standard 2. Your foam is fine and is a vapor barrier so don t put another one in there. Follow with a 2x4 frame wall and insulate it with batt insulation. That would be 3 inches of polyiso you mentioned two other goals.

R 6 polyisocyanurate rigid foam insulation board model 787264 21 78 21 78. Set your store to. Either r 43 or r 53. Thermasheath rmax thermasheath 3 1 in.

Insulation s r value is a measure of its effectiveness and a single 1 inch sheet of polyurethane foam gives you an r value of 5 5 to 6 5 according to the u s. After that thin furring strips are installed on top of the foam to provide a firm base for the drywall screws and drywall but can you run rigid foam between the studs just as you would do with fiberglass rolls or spray foam. Attach the tongue and groove insulation boards to the concrete wall with adhesive. Once the insulation is in the wall and sealed up with drywall it is not easy to change out.

When you are insulating two by four 2x4 and two by six 2x6 framed exterior walls and want to use fiberglass insulation what thickness is best the question becomes all more critical because of the permanent nature of wall assemblies and wall insulation. Truck tool rental.