Guides and Case Studies for Cold and Very Cold Climates

Map of the Cold & Very Cold Zones of the United States. The far tips of North Dakota, Maine, and southern Alaska are shown as Very Cold. The northern half of the United States is labeled Cold.

The Department of Energy (DOE) has developed a series of best practices and case studies to help builders improve whole-house energy performance in buildings found in cold and very cold climates.

Best Practice Guides

New Construction Case Studies

Colorado

Project: Burlingame Ranch Phase 1 — Aspen
Builder: Shaw Construction
Profile: 84 multi-family affordable units score HERS of 54-62 in extreme cold climate with spray foam wall, ceiling, and subslab insulation, hydronic baseboard heat preheated by solar thermal panels.

Project: Net Zero Demonstration Home — Boulder
Builder: Ecofutures Building, Inc.
Profile: Builders Challenge demonstration home with superior insulation and 8.9 kW photovoltaics (PV) achieve -3 HERS score.

Connecticut

Project: Hamilton Way — Farmington
Builder: Nelson Construction
Profile: 10 single-family homes score HERS 53-54 with polyiso sheathing, spray foam critical seal at rim joists and attic plus R-50 blown fiberglass in attic, 6 inner-city infill single-family homes raise property values in rundown neighborhood, score HERS 51-55 with blown fiberglass R-24 walls, R-49 attics, precast concrete insulated basement walls, high-effic HVAC and ducts in conditioned space.

Indiana

Project: The Gem Prototype - Burns Harbor
Builder: Treasure Homes Inc.
Profile: Insulated concrete form basement walls, SIPS above-grade walls, spray-foamed rim joists and attic for 95 AFUE furnace in conditioned space scores HERS 46 without PV.

Massachusetts

Project: Colrain House — Turner Falls
Builder: Rural Development Inc.
Profile: Builders Challenge spotlight on prototype home incorporating energy efficiency and PV to reach HERS index score of 21.

Project: Wisdom Way Solar Village — Greenfield
Builder: Rural Development Inc.
Profile: 20 multi-family affordable homes achieve HERS 8-18 with single-family homes score HERS 53-54 with stud-framed double walls cellulose-insulated to R-42, R-50 attic, triple pane windows, solar water heating and PV, sealed combustion gas space heaters.

Michigan

Project: Vision Zero Project - Sagina
Builder: Cobblestone Homes
Profile: Demonstration home scores -4 on HERS index with double layer of rigid foam wall insulation plus spray foam wall and ceiling insulation, and ground-source heat pump heating, cooling, and water heating.

Pennsylvania

Project Name: East Liberty — Pittsburgh
Builder: S&A Homes and East Liberty Development Inc. Profile: 6 inner-city infill single-family homes raise property values in rundown neighborhood, score HERS 51-55 with blown fiberglass R-24 walls, R-49 attics, precast concrete insulated basement walls, tight seal, 96% AFUE, 14 SEER HVAC.

Project Name: Summerset at Frick Park — Pittsburgh
Builder: Kacin Homes
Profile: Development of highly efficient homes on former industrial site; prototype home achieves energy savings of 38% over benchmark.

Utah

Project: CDC Utah — Magna
Builder: Community Development Corporation of Utah
Profile: Builders Challenge spotlight on affordable energy-efficient homes achieving 32% energy savings over the Building America benchmark.

Washington

Project: Mediterranean Villas — Pasco
Builder: Devoted Builders LLC
Profile: 230 high-end Built Green-certified duplexes and triplexes score HERS 54-68 with insulated concrete form walls, heat pumps, low air leakage of 0.8 to 2.0 ACH50, heat recovery ventilation.

Wisconsin

Project: Net Zero Demonstration Home — Waukesha
Builder: Tim O'Brien Homes
Profile: Builders Challenge demonstration home achieving -3 HERS score with enhanced insulation, geothermal heat pump, PV and solar hot water heating system.

Improvements to Existing Homes Case Studies

New York

Project: Newburgh Historic Row House Retrofit — Newburgh
Builder: Habitat for Humanity of Greater Newburgh, Inc.
Profile: Using cold-climate, high-performance retrofit strategies, this project created affordable, energy-efficient homes for low-income families.

Pennsylvania

Project: Depression-Era Demonstration Retrofit — Pittsburgh
Builder: Asdal Builders, LLC
Profile: The retrofit of this 1930s-era bungalow resulted in a HERS score of 65 and 80% reduction in overall energy use.

Washington

Project: System Retrofit Package Design — Wapato
Builder: Yakama Nation Housing Authority
Profile: This project used a "system retrofit package" to improve efficiency of 25 single-family homes on the Yakama Indian Reservation, cutting energy use in half and creating a model for replication across 4,300 homes built on U.S. reservations.

Solutions That Work Across Climates

DOE has developed several building solutions that work across climate regions.

For additional, updated information on hundreds of building science topics that can help you build or retrofit to the most recent high-performance construction criteria, including the latest version of ENERGY STAR and the DOE Challenge Home requirements, see the Building America Solution Center.