Ventilated Roof Sheathing

Grab a flashlight and inspect your attic during the winter.

Ventilated roof sheathing.

30 times stronger than equivalent plywood or osb. The roof sheathing shall be cornell ventilated roof sheathing manufactured by cornell corporation p o. Box 33s cornell wl 54732 tele. When the attic becomes part of the home to be heated and cooled open wall gable vents and roof vents are no longer feasible but the underside of the roof the sheathing and rafters can still.

The wood spacers shall. The map at right which is based on table r806 4 of the irc lists the minimum r values required to prevent condensation in unvented assemblies in various climate zones. If you see dampness or frost you need better roof ventilation and some attic vents. R vent is a 40 recycled ventilation mat used in cedar metal tile roof construction.

Integral ventilation provides energy savings and extends the life of roofing and siding. It shall consist of 7 16 optional 5 8 or 3 4 oriented strand board sheathing with 1 deep wood spacers secured to the underside of each 4 x 8 panel. Superior strength reduces framing saving thousands in construction costs. This above sheathing ventilation or asv inherent to tile roof installations can be enhanced using counter battens shims or manufactured systems to raise the horizontal battens above the roof deck.

Up to 1 50 ventilation ratios possible with new matrix members. The system design will vary with the environmental challenge and goals. The amount of cooling provided by a well ventilated roof exposed to the sun is very small. An unvented roof assembly is possible only if you keep the roof sheathing warm enough to prevent conditioned air from condensing against it.

Warm air that escapes living space also carries moisture that will condense on rafters or roof sheathing. The standard 1 vent space layout leaves over 92 open vent area for maximum airflow. 7 16 osb is standard and 5 8 or 3 4 osb or plywood and. Field monitoring of numerous attics has confirmed that the temperature of the roof sheathing of a unvented roof will rise by a few to no more than 10 f more than a well ventilated attic.

A strong resilient roof is a home s first line of defense when the roof deck is exposed to weather. For the best results place roof ventilation near the roof s peak and soffit vents in the eaves. Thermacal 1 and 2 ventilated roof insulation panels are composite ventilated roof insulation panels combining standard osb sheathing an air space made by solid wood spacers and polyisocynurate.