Insulation Rebate Information for Residential Homes

Thank you for your interest in the residential insulation rebate. Please review the following information and requirements related to your project. For more information regarding required insulation specifications, please refer to Bonneville Power Administration’s Weatherization Specs and Best Practices Guide.

Required Rebate Documents

When your project has been completed, please submit your required documents with your application or e-mail them to rebates@esgroupllc.com.

Required Documents for the Insulation Rebate

  • Copies of contractor final invoice(s) noting:
    • R-value of final insulation
    • The square footage of added insulation
    • The total cost of labor and materials
    • The invoice date
  • Proof of the original insulation levels before the project was completed, if not already submitted. This may either be documented on the contractor’s invoice or by providing clear pictures of the insulation showing its depth with a ruler.
  • Clear pictures of the new insulation showing its depth with a ruler. If you are unable to provide pictures, we may provide a free on-site insulation inspection after we have received all other required documentation, depending on availability. Please contact us at (888) 883-9879 or rebates@esgroupllc.com to determine eligibility and scheduling for an inspection.

Please note: We cannot rebate on insulation manufacturer quotes, proposals, or estimates. All manufacturer orders must be final.

Home & Heating Requirements

The insulation rebate applies to existing Site-Built Single-Family (4 units or less), Multifamily (5 units or more), and Manufactured homes. New construction homes do not qualify.

Homes must be heated with an electric heating system. The following heating systems qualify:

  • Electric Forced-Air Furance
  • Heat Pump
  • Ductless Heat Pump
  • Electric Baseboards
  • Electric Wall Units
  • Electric Portable Space Heaters
  • Ceiling Cable

If your home has an electric heating system that is not listed, please reach out to our energy efficiency department at (888) 883-9879 or rebates@esgroupllc.com to determine eligibility.

For homes heated with gas, please contact your gas provider to see rebates that may be available to you.

Project Requirements & Specifications

The Bonneville Power Administration (BPA) has constructed a list of installation and specification requirements that must be followed to receive the insulation rebate. Both contractors and self-installers should use these requirements as a checklist when installing insulation. Proper installations and insulation specifications are verified before rebates are processed. For a more comprehensive installation guide, please refer to Bonneville Power Administration’s Weatherization Specs and Best Practices Guide.

Single-Family & Multi-Family Attic Insulation

Attic/Roof Preparation

  • Remove all degradable and absorbent scrap materials from the attic that might eventually rot and damage the structure, especially wood and cardboard.
  • Repair any water leaks and moisture damage prior to performing work.

Attic Insulation Shields

  • Insulation shields must extend at least 4 inches above the level of the new insulation, and any insulation must be removed from the top and inside of the insulation shield.

Insulation Dams and Baffles

  • Insulation dams maintain the insulation’s full R-value to the edge of an insulated space, and prevent blown insulation from blocking vents or sloughing where insulation levels differ or spilling into uninsulated areas.
  • Insulation dams must use one of the following two methods:
    • Build dams with rigid materials such as plywood, OSB, foam board, or cardboard.
    • Permanently secure the dam to attic framing.
  • Rigid dams must extend 4 inches above the final level of the insulation.
  • Whenever fibrous insulation is installed where occupants might access for storage or maintenance, contractors must cover the fibrous insulation with a vapor-permeable air barrier (for example: house wrap, drywall).

Baffles for Eave and Soffit Vents

  • Remove any existing insulation or other debris from the eave or soffit vents.
  • Baffles must be rigid and air impermeable.
  • Baffles must extend at least 4 inches above the final level of insulation.
  • Maintain an opening between the baffle and the roof sheathing equal to or greater than the area of the soffit vent.
  • Install the baffle far enough into the rafter bay to reach the exterior side of the top plate in order to achieve the best R-value possible above the top plate.
  • Fasten the baffles to the roof rafters with no less than 9/16-inch galvanized staples or roofing nails.
  • Where a continuous soffit vent exists, install a baffle in each rafter bay.
  • Install baffles, equally spaced along the soffit. Seal the unbaffled rafter bays with a rigid, moisture-resistant material.

Pipe Insulation

Exposed water pipes in attics may freeze or lose energy to the cold air.

  • If water or hydronic pipes won’t be covered by at least one inch of attic insulation, wrap the pipes according to “11 Hydronic and Water-Pipe Insulation.” Insulate the walls to a minimum of R-11 for a 2×4 cavity, and R-21 for a 2×6 cavity.

Exhaust Fans

New and existing exhaust fans must vent directly to the outdoors (through a roof jack, gable or wall) and never into an attic or into another location within the home.

Exhaust Fans and Ducts

Ducts for kitchen fans and bathroom fans must comply with all the following bolded requirements. Additional recommended best practice steps are included as well.

  • Exhaust ducts must be sheet metal or HVAC flex-duct and insulated to a minimum of R-4 if in unconditioned space. Vinyl coil ducts must be replaced.
  • Any newly installed exhaust ducts must be sized according to “Appendix 2: Exhaust Fan Prescriptive Duct Sizing.”
  • All exhaust fans must vent to the outdoors.
  • Ducts must be mechanically fastened using sheet metal screw or clamps and be substantially airtight.
  • Mechanical fasteners must not interfere with dampers.
  • Exhaust fan ducts should be adequately supported to prevent sagging, be as straight as possible to maximize effective air flow, and have no more than two 90-degree turns, or equivalent.
  • Kitchen exhaust ducts must be made of 28-gauge galvanized steel, stainless steel, aluminum or copper.
  • Existing rigid or flexible metal vent ducts may remain if they are free of holes and kinks and are otherwise in good condition.

Blown Attic Insulation

Install loose-fill insulation to the surface between the conditioned space and attic with a uniform R-value.

  • Install one insulation depth ruler for every 300 square feet of attic area. Depth rulers should face the attic entrance.
  • Pack insulation against the eave baffle or roof deck to achieve the highest possible R-value in places where the full intended thickness of insulation won’t fit.
  • Install insulation to a consistent depth. Level the insulation if necessary.
  • Post an Installer Record at the electrical panel, circuit box, or other location approved by the homeowner as a record of work performed.

Batt-type Insulation

  • Install batts in contact with the surface between the conditioned space and attic, cut to fit, placed tightly together with no gaps except those required for clearance around heat-producing fixtures.
  • Install baffles and shields prior to installing batt-type insulation.
  • Cover the exterior of the top plates of exterior walls. You may compress the batts at the eaves if necessary to cover the top plates.

Foam Insulation

In an open attic, a sloped roof cavity, or an attic knee wall, both spray and rigid foam are acceptable types of insulation, provided they meet the following requirements.

  • The foam insulation must meet the minimum requirements for R-value.
  • Contractors must install the foam insulation in contact with the surface that separates attic and conditioned space.

Interior Attic Access Doors

Access doors must be insulated and sealed in a durable and effective manner.

  • Permanently attach weatherstripping to the attic-access door or frame to create an effective air seal between the door frame and the door.
  • Repair air leaks or replace the door prior to insulating.
  • Whenever fibrous insulation is installed where occupants might access for storage or maintenance, contractors must cover the fibrous insulation with a vapor-permeable air barrier (for example: house wrap).

Walls in Attic Areas

Comply with all of these bolded requirements for open walls in attic areas.

  • Seal all penetrations through the wall with caulk or foam.
  • Install wall insulation prior to installing ceiling insulation. This insulation must be a minimum of R-11 in a 2×4 cavity, and R-21 in a 2×6 cavity.
  • When adding new insulation over existing wall insulation, completely fill the cavity.
  • If you install a vapor retarder, install it in contact with the heated surface. Heated surface is commonly referred to as the air barrier.
  • Cover new attic wall insulation with a durable, vapor-permeable air barrier material to prevent air penetration of the insulation and to ensure that the insulation is held in full contact with the wall.
  • Fasten the air-barrier material so that it permanently supports the knee wall insulation.
  • Insulate knee wall access door and hatches to R-11 and weatherstrip them to create an effective air seal. Pre-manufactured foam-core doors are an acceptable option. If side attic area will be accessed (used for storage), cover the insulation with a vaporpermeable material.

Floored Attics

Comply with these requirements when insulating under floor boards of floored attics.

  • Cavities below decked storage areas must be insulated to the highest practical level.
  • Insulate under attic floorboards with tightly packed blown fibrous insulation.

To fill the cavities, lift the boards or drill holes no more than 4 feet apart. Avoid over-filling the cavities because the pressure can damage the ceiling materials below.

  • If installing insulation in non-decked areas of the attic, prevent loose-fill insulation from falling onto the storage deck using a dam.

Manufactured Homes Roof Insulation

  • Seal all ceiling penetrations before insulating ceiling cavities.
  • If the ceiling cavity contains a non-ducted return-air system, seal the opening to the attic and provide return air, either through ductwork or vent to the main area of the home.
  • Insulate ceiling cavities under flat or crowned metal roofs by completely filling them with blown-in fiberglass insulation.

Single-Family & Multi-Family Floor Insulation

Preparation for Underfloor Insulation

When a contractor installs underfloor insulation in a site-built home, these preparatory steps are required.

  • Remove all degradable and absorbent scrap materials from the crawlspace, especially wood and cardboard. These materials may eventually rot and damage the structure.
  • Repair any water leaks and moisture damage prior to performing work.

Ground-Moisture Barrier

Verify that a ground-moisture barrier is present in the crawlspace or install a new ground-moisture barrier before installing underfloor insulation. Comply with these bolded requirements when verifying, installing or retrofitting a ground-moisture barrier. Additional recommended best practice steps are included as well.

Acceptable materials for a ground-moisture barrier include the following:

  1. 6-mil black polyethylene.
  2. UV-stabilized and opaque polyethylene.
  3. Existing black 4 mil polyethylene may remain if it’s in good condition.
  • Overlap seams by 12 inches.
  • Treat unconditioned basements with exposed soil the way you would a vented crawlspace.
  • Cover the exposed soil with a ground-moisture barrier.

Crawlspace Ventilation

  • Crawlspaces weatherized with underfloor insulation must be vented by openings in exterior foundation walls or rim joists.
  • The total net free area of foundation vents must not be less than 1 square foot for each 150 square feet of underfloor area as a default standard.
  • Vent openings must be covered with corrosion-resistant wire mesh with openings not more than 1/4- inch in width or length.
  • Where soil moisture isn’t considered excessive, a code official or the local serving utility representative may reduce the ratio to 1 square foot of vent for each 1500 square feet of underfloor area.
  • Vent openings must be located close to corners and provide cross ventilation in the crawlspace.

Water Pipes in Crawlspaces

  • Fiberglass batts used in floor insulation must be cut to fit around pipes with no voids or compression.

Indoor Access Doors for Underfloor Areas

Insulate any interior crawlspace access door to at least R-25 for horizontal openings and to at least R-11 for vertical openings.

  • Weatherstrip all inside access doors and hatches.
  • Insulate as much of the door as possible without affecting the door operation.
  • Fiberglass batts must be covered with a vapor-permeable air barrier material when regular access by people occurs.

Installing Underfloor Insulation

Insulate the floor to the maximum amount practical. Check with local code or the local serving utility weatherization programs for minimum insulation requirements.

Installing Fiberglass Batt Insulation

Comply with these bolded requirements when installing fiberglass batts in floor-joist spaces of the underfloor.

  • Cut batts to fit around water pipes, drain pipes, or other obstructions so no gaps or voids exist.
  • If the installed batt has a vapor retarder facing (Kraft paper or foil-Kraft), the facing must be installed against the floor sheathing.
  • Use one of the following materials to support floor insulation.
    • Wood lath—Wood lath needs to be a minimum of ¼ x 1 inch for spans up to 48 inches. Spans greater than 48 inches must use at a minimum nominal 1×2 lumber.
    • Twine—Twine must be non-stretching polypropylene or polyester.
    • Wire—Wire must be stainless steel, copper or an equivalent material of similar corrosion resistance, with a minimum diameter of 0.040 inch (size 18 AWG).

Installing Blown Insulation

  • Blow only fiberglass or rock wool loose-fill insulation in a floor cavity.

Manufactured Homes Floor Insulation

Preparation for Underfloor Insulation

Before installing either blown or fiberglass batt underfloor insulation, take these steps to prepare the home.

  • Install a ground cover in the crawlspace.
  • If the floor contains a non-ducted return system, seal the opening to the crawlspace and provide return air, either by installing new return ducts or by installing a vent between the furnace-closet door and the main area of the home.
  • Extend all water drains to the outside of the crawlspace, including condensate drains from air conditioning equipment.
  • Extend all exhaust ducts, such as those for kitchen ranges and dryers, to the outside of the crawlspace.

Blown Underfloor Insulation

In order to successfully install blown insulation, the rodent barrier must be in good or repairable condition.

Contractors must comply with the below requirements installing for blown floor insulation.

  • Materials used to patch the rodent barrier must be vapor-permeable, durable and capable of supporting the insulation.
  • Repair large holes in the rodent barrier to prevent insulation from falling into the crawlspace from the floor cavity.

Fiberglass Batt Underfloor Insulation

Comply with these insulation requirements when adding fiberglass batts to the floor-joist cavity of a manufactured home.

  • Install fiberglass batts to achieve a minimum of R-22 or the maximum R-value achievable with no air space between the insulation and the subfloor. Contractors may compress the batts in order to maintain continuous contact with the bottom of the floor.
  • Skirting must be as close to the ground as practical and prevent the entry of animals.

Insulating Unfinished Walls

Comply with the following requirement when insulating unfinished walls.

  • Insulate walls to a minimum of R-11 for masonry or for nominal 4 inch walls and to a minimum of R-21 for nominal 6 inch walls.