Residential Oversheathing Roof Insulaiton
Nail it around the edges with roofing nails.
Residential oversheathing roof insulaiton. It s not coming from above the roof and it s not some new moisture source resulting from the spray foam. Moisture generated indoors or that infiltrates into the home is responsible for the bulk of the moisture in an attic insulated with spray foam on the underside of the roof sheathing. This concept while not new has become more accepted in recent years and is being used in residential construction. Don t let your heating costs go through the roof.
With more than 60 years of being used nation wide insulfoam roof insulations are a proven value. 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. If you prefer not to use rigid foam you can use mineral wool panels instead. 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.
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. 1 inch and 2 inch thicknesses are common. Lstiburek takes blame for bad language. Install insulating sheathing above the roof deck on existing homes.
Insulated roof assemblies can be vented or unvented. With this kind of roof the insulation follows the slope of the roof. R panel is manufactured with a closed cell polyisocyanurate foam core bonded to fiberglass reinforced facers and designed for use over metal nailable and non nailable roof decks with a variety of membrane systems. For more information on this option see installing mineral wool insulation over exterior wall sheathing.
Over roof insulation the gable overhang has been cut flush with the wall sheathing. Remove existing roofing and non adhered underlayment to expose roof sheathing. 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. A roof over a vented unconditioned attic does not need to include any insulation.
The boards are available in several thicknesses and r values. This retrofit assembly is appropriate for homes with conditioned attics or where the retrofit is intended to create a conditioned attic. Johns manville r panel rigid roof insulation board offers r values of up to r 23 6 providing high thermal efficiency.