Rigid Foam Roof Sheathing

On the gable ends this was pretty easy.

Rigid foam roof sheathing.

1 inch and 2 inch thicknesses are common. Rigid foam sheathing 3. Johns manville polyiso foam sheathing insulation boards provide a continuous layer of insulation to reduce thermal bridging and improve energy efficiency. Not only that foam sheathing will soon be mandated by code in some climate zones.

This foam is applied over the top of the membrane that came down from the roof deck catching the wall control layers. Rigid foam insulation packs a lot of r value into a thin package but not all rigid foam performs the same. Cold formed metal framing c. Choose rigid insulation wisely and consider the effect its characteristics will have on the performance of the your project overall product cost and the best way to get the bang for your buck.

Replacement of a roof membrane where either the roof sheathing or roof insulation is not exposed or if there is existing roof insulation below the roof deck. Install rigid insulation board in multiple layers with joints offset vertically and horizontally between adjacent layers. Rigid insulation provides thermal protection and it can also serve as an air and moisture barrier. Rigid foam insulation also known as insulating boards provide high r values.

Install it anywhere from the roof to the foundation. Rigid insulation sheathing is made of a rigid plastic foam that is typically sold in 4 8 or 4 10 foot boards. Alterations to roof ceiling wall or floor cavities which are insulated to full depth with insulation having a minimum nominal value of r 3 0 in. Rigid insulation layers exterior to existing roof sheathing must provide sufficient thermal insulation r value to control condensation risk see climate specific guidance.

The boards are available in several thicknesses and r values. One of the keys to over roofing is to tie the air control layer of the roof assembly to the air control layer of the wall assembly. Detail roof wall intersection and all openings and penetrations to provide a continuous air barrier system. Rigid insulation is one of the best tools to reduce your energy costs.

Install nailbase for cladding. Exterior rigid foam improves air tightness adds r value reduces the chance of condensation in wall cavities and greatly reduces thermal bridging through studs. The purpose of the requirement that rigid foam installed above roof sheathing meet certain minimum r values is to ensure that the roof sheathing stays warm enough during the winter to avoid moisture accumulation and possible sheathing rot. Air barrier system 4.