Residential Oversheathing Roof Insulaiton

Continuous rigid insulation is a construction solution that provides a thermally efficient building enclosure.

Residential oversheathing roof insulaiton.

Remove existing roofing and non adhered underlayment to expose roof sheathing. This concept while not new has become more accepted in recent years and is being used in residential construction. Nail it around the edges with roofing nails. This retrofit assembly is appropriate for homes with conditioned attics or where the retrofit is intended to create a conditioned attic.

Over roof insulation the gable overhang has been cut flush with the wall sheathing. Start at the bottom of the roof and place the first piece of rigid foam insulation against the metal flashing starting at the center line. Residential roof insulation insulfoam offers a wide variety of faced laminated and standard high performance eps insulation products for all your new and re roofing needs. Lstiburek takes blame for bad language.

A roof over a vented unconditioned attic does not need to include any insulation. It s not coming from above the roof and it s not some new moisture source resulting from the spray foam. Don t let your heating costs go through the roof. Johns manville r panel rigid roof insulation board offers r values of up to r 23 6 providing high thermal efficiency.

Also note that a new fully adhered membrane is installed on the original roof deck replacing the one installed 17 years ago is folded down to catch the top edge of the wall water control layer. With this kind of roof the insulation follows the slope of the roof. Rigid insulation sheathing is made of a rigid plastic foam that is typically sold in 4 8 or 4 10 foot boards. In cold climates the use of exterior rigid insulation sheathing boards has been a method of increasing thermal performance of the enclosure as well as a means of reducing the condensation potential within exterior wall assemblies.

If you prefer not to use rigid foam you can use mineral wool panels instead. The boards are available in several thicknesses and r values. For more information on this option see installing mineral wool insulation over exterior wall sheathing. Install insulating sheathing above the roof deck on existing homes.

With more than 60 years of being used nation wide insulfoam roof insulations are a proven value. However most cathedral ceilings and low slope flat roofs are insulated roof assemblies. 1 inch and 2 inch thicknesses are common.