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Schematic of exterior insulated roof assembly

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Above Deck Rigid Foam Insulation for Existing Roofs

Guide

Guide describing the installation of insulating sheathing above the roof deck on existing homes. This retrofit assembly is appropriate for homes with conditioned attics or where the retrofit is intended to create a conditioned attic.

Application of Spray Foam Insulation Under Plywood and OSB Roof Sheathing

Video

Video describing how to air seal attic rafters with spray foam.

To reduce the risk of condensation on the interior of the roof sheathing in cold weather, the ratio of exterior (above-deck) insulation must be increased as a percent of total attic insulation as outside temperature decreases

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Water Managed Roof – Re-roofing and Adding Insulation Over a Sloped Roof

Guide

Guide describing how to re-roof an existing home with a sloped roof and add insulation above the roof deck.

Sloped roof with cavity spray foam insulation, strapping, and gypsum board thermal barrier

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Flat roof with cavity spray foam plus loose-fill insulation and gypsum board thermal barrier.

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Sloped roof with cavity spray foam insulation sprayed on underside of roof deck and covered with sprayed-on thermal or ignition barrier coating.

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Retrofit an existing roof by installing rigid foam, new moisture and air control layers, new sheathing, and new cladding plus cavity insulation in the roof rafters to create an unvented attic

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Roof/Attic to Exterior Wall Air Control Upgrade

Guide

Guide describing how to retrofit an exterior wall and/or attic to provide continuous air sealing.

Right – R-23 of blown fiberglass fills the walls and unvented vaulted attic cavities of this marine-climate home while an additional R-20 (4-inches) of graphite-enhanced expanded polystyrene is installed above the roof sheathing.

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Building in Extreme Cold, BSI-031

Reference

Article describing the control layers (air, thermal, and vapor barriers) needed to build homes successfully in very cold locations.

Unvented roof assembly at rake retrofitted with a filler piece and taped top edge of existing house wrap or building paper to seal the top of wall-to-roof transition

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Lateral Bracing in Gable End Walls

Guide

Guide describing how to brace gable end walls to resist wind pressures.