The roof area can be the area of highest heat loss in buildings, allowing up to 25% of your heat to escape through uninsulated roof and attic spaces. In order to conserve energy and to make buildings more comfortable, building codes stipulate higher thermal resistances (R-values) for the roof area compared to other building components.

Insulating your cathedral ceiling with Plasti-Fab’s rigid EPS insulation products allows you to keep the vaulted ceilings and increase your energy efficiency. This insulation solution can be installed during a new construction or done as a renovation project.

EPS insulation is ideal for this type of application due to its rigid material properties, long term thermal resistance (won’t lose R-value over time), and easy installation.

With the dependable distribution network of Plasti-Fab EPS insulation products and technical expertise readily available. To learn how to install cathedral ceiling insulation, check out the Installation Instructions tab for a step by step guide to creating a more energy efficient home.

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Durofoam Insulating Under a Basement Slab

1. Follow the Building Code

Be sure to follow the building code requirements applicable in your region.

Durofoam Insulating Above a Basement Slab

2. First Layer of Insulation

Use nailers the same thickness as the first layer of insulation. Lay nailer, then insulation, then nailer up the slope of the roof, all joints tightly butted. Fasten nailer to deck as work proceeds.

Durofoam Insulating Exterior Foundation Walls

3. Second Layer of Insulation

Lay second layer of insulation perpendicular to first layer. Lay insulation with joints tightly butted. Lay nailers over insulation spaced to support roof sheathing. Second layer of nailers to achieve a minimum airspace as determined by local building code.

Durofoam Insulating Under a Basement Slab

4. Fastening Layers of Insulation

Fasten second layer nailer to first layer nailer where they intersect. If the thermal resistance requires extra layers of insulation, add layers to the bottom of the system changing the nailer direction as required. The top nailer must always run from the bottom of the roof slope to the ridge of roof.

Durofoam Insulating Above a Basement Slab

5. Finish

Nail roof sheathing to nailers taking care that air movement is unobstructed in ventilation space.

Durofoam Insulating Exterior Foundation Walls

6. Roofing Cover

Install roof covering in accordance with manufacturer's instructions. Adequate ventilation must be insured using an acceptable method to the applicable building code and/or local regulations.

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