THERMWISE WEATHERIZATION (For Existing Homes Only) Weatherization Requirements Rebate Windows U-Value of 0.35 $0.95 per square foot Wall Insulation Increments of R-11 or higher $0.45 per square foot Attic/Floor Insulation Increments of R-19 or higher $0.35 per square foot Duct Sealing* Professional install to PTCS level $225 Duct Insulation* Professional install to R-6 or higher $250 * Duct Sealing and Duct Insulation must be installed by a Questar Gas-approved contractor. To apply for ThermWise Weatherization Rebates: Print, complete and mail the Weatherization Rebates Application Weatherization rebates also available to Multifamily Property Owners. Refer to ThermWise Multifamily Rebates Program for details and application forms. Please see Terms and Conditions before you apply.