BASC Search | Building America Solution Center

New Code Options for Insulating, Sealing, and Controlling Moisture in Unvented Attics in Residential Buildings

Presentation

Webinar explaining new code options for insulating, sealing, and controlling moisture in unvented attics in residential buildings.

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

Image

Cut two pieces of sheet metal to fit around the flue

Image

Installation of Cavity Insulation, Info-501

Reference

Article explaining installing cavity insulation.

Venting Vapor, BSI-088

Reference

Guide providing information on controlling attic ductwork sweating.

Vented roof assembly at rake retrofitted with spray foam and additional insulation installed at the attic floor and extended to the rake edge

Image

Measure Guideline: Guide to Attic Air Sealing

Reference

Guideline describing information and specifications relevant to air-seal existing attics.

Vented roof assembly at eave retrofitted with rigid foam, spray foam, and fully adhered membrane to air seal the top of wall-to-roof transition

Image

Seal all drywall-to-top plate seams and penetrations at the attic floor

Image

Attic or Roof? An Evaluation of Two Advanced Weatherization Packages, BA-1205

Reference

Report about a project that examines implementation of advanced retrofit measures in the context of a large-scale weatherization program and the archetypal Chicago, Illinois, brick bungalow.

Unvented roof assembly at eave retrofitted with rigid foam, spray foam, and a fully adhered membrane seal at the top of wall-to-roof transition

Image

Batt insulation is installed in two layers in perpendicular directions against the baffle to full required insulation height

Image

Batt insulation is installed in two layers with offset seams against the baffle to full code-required insulation height

Image

Attic Air Sealing Guide and Details, GM-1001

Reference

Document providing background and approach for the prep work necessary prior to adding attic insulation - focusing on combustion safety, ventilation for indoor air quality, and attic ventilation for durability.

Clean the attic floor of debris prior to installing new attic insulation. Use baffles to provide a path for ventilation air entering the attic from the soffit vents

Image

Seal the drywall to top-plate seams and the lower edge of baffles to the top plate to prevent the air coming from soffit vents from flowing under baffles into insulation.

Image

Air Sealing Drywall to Top Plate

Guide

Guide describing ways to seal drywall to the top plate of an exterior wall to air-seal the wall cavity.

Unvented Attic Insulation

Guide

Guide describing methods for insulating an unvented attic along the roof line.

Air Sealing Bathroom and Kitchen Exhaust Fans

Guide

Guide describing how to air-seal bathroom and kitchen exhaust fans.

Install Top Plates or Blocking at the Top of Walls Adjoining Unconditioned Spaces

Guide

Guide describing how to correctly air-seal a wall with missing top plates or open wall cavities.

Spray Foam Insulation Applied to Existing Attic Floor

Guide

Guide describing how to apply spray foam insulation to the floor of the attic in existing homes.

Walls Adjoining Porch Roof

Guide

This guide describes how to install a rigid air barrier to separate the porch attic from the conditioned space.

Air Sealing Duct and Flue Shafts

Guide

Guide describing how to air-seal duct and flue shafts.

Dropped Ceiling/Soffit Below Unconditioned Attic

Guide

Guide describing how to insulate and air-seal dropped ceilings and soffits to prevent air leakage.

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.

Attic Air Sealing, Insulating, and Ventilating for Ice Dam Prevention

Information Guide

Information guide describing proper attic air-sealing, insulation, and ventilation to combat ice dam formation on roofs in cold climate zones.

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.

Air Seal HVAC Cabinet Seams

Guide

Guide describing air-sealing of the seams and holes in HVAC air handler and furnace cabinets.