Rigid Insulation Roof Sheathing

Rigid insulation sheathing is made of a rigid plastic foam that is typically sold in 4 8 or 4 10 foot boards.

Rigid insulation roof sheathing.

You can even place it under the foundation slab. Install nailbase for cladding. After installing several layers of rigid foam above the roof sheathing these workers installed plywood above the rigid foam. The exposed edges of the 3 layers of rigid insulation are to be sealed with another layer of membrane.

Rigid foam insulation also known as insulating boards provide high r values. The rigid board sheathing has a one inch layer of continuous insulation for maximium wall and worksite efficieny. Here you can find overstock discontinued non standard sizes and more. Install roofing underlayment flashing and cladding as per best practices.

This type of insulated roof assembly limits thermal bridging through rafters. Box beam gable framing new gable overhang is framed in the form of a box beam hanging off of a new layer of roof plywood roof sheathing cantilevered over the top of the 3 layers of rigid insulation. The glass fiber reinforcement contributes to improved fire performance and dimensional stability. Thermax sheathing is a former product of the dow chemical company.

Install it anywhere from the roof to the foundation. Insulation for an exposed ceiling must be located above the sheathing. Rigid insulation provides thermal protection and it can also serve as an air and moisture barrier. The boards are available in several thicknesses and r values.

1 inch and 2 inch thicknesses are common. Insulation requirements will vary with climate and with roofing material. The plywood was fastened through the rigid foam to the rafters with long screws. All rigid insulation meets astm c578 requirements and is offered at a discount.

Nailbase must be vented in high snow load areas. The exposed edges of the 3 layers of rigid insulation are no longer exposed. Rigid insulation layers exterior to existing roof sheathing must provide sufficient thermal insulation r value to control condensation risk see climate specific guidance. Rigid insulation board is available in quantities ranging from individual foam sheathing to bundles to units.

Rigid insulation is usually the most practical because of its thin profile but it is more expensive than batt insulation. 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. Effective resistance to heat transfer with r values up to r 28.