Southwest Energy Efficiency Project

Aspen Homes of Colorado

Aspen Homes is a small production builder that constructs homes that will perform up to 40 percent better than a typical home built to code, yet are affordable to the average homebuyer. 100% of Aspen homes exceed the requirements of ENERGY STAR and Built Green Colorado. Each home also includes a 2-year heating consumption guarantee for the homeowner.ⁱ

The energy efficiency features of Aspen Homes include the following:ⁱⁱ

Enhanced wall, ceiling and slab insulation.
External wall system features include blown-in insulation (R-15 blown-in fiberglass and one-inch extruded polystyrene foam. Ceilings use cellulose insulation (R-42). The exterior basement walls and the perimeter of at-grade slabs are insulated with R-10 (2” thick) extruded polystyrene rigid board. The basement wall and slab insulation helps keep the floor slab warm and minimize heat loss to the ground.
Highly-efficient HVAC and ducts, including a sealed-combustion, properly-sized furnace, and ducts that are properly sealed, pressure balanced and tested (less than 10% leakage rate). Ducts are placed entirely inside the conditioned space. The furnace is centrally located in the basement to minimize duct runs.
Extensive home sealing (e.g., foam sealing voids in the rim joist, foam sealing mechanical penetrations, caulking around window and door frames, weather stripping around the attic hatch and exterior doors, caulking top and bottom plates, and gluing the drywall to the top and bottom plate with subfloor adhesive, and exterior wall insulation around showers and baths).
Installation of the ENERGY STAR “Indoor Air Package” to maintain indoor air quality. The system includes a mechanical ventilation system to exchange indoor and outside air.ⁱⁱⁱ
Gas tankless water heater.
Diagnostic testing: HERS rating and duct diagnostic testing.

Since 2002, the company has built more than 500 ENERGY STAR homes. Aspen Homes received the Built Green Colorado ‘Home of the Year’ Award in 2006, the 2007 Energy Value Housing Award from the NAHB, and was named the 2006 ENERGY STAR Partner of the Year. Aspen Homes has also received recognition for building energy efficient affordable housing.^iv

Lessons learned

Air sealing and insulation are highly cost-effective measures, but should be implemented as components of a whole-systems approach.
Highly-efficient affordable homes can be built cost-effectively in cold climates.
Homeowner involvement is critical to achieving high levels of home energy performance. The company provides information about the energy efficiency features and benefits to each homeowner at a pre-construction meeting, and again during construction walk-throughs and post-closing walk-throughs. Simpler, straightforward messages about tangible energy savings are more effective than detailed information in conveying the benefits of energy efficient homes to homebuyers.
High performance homes can help improve sales, particularly during market downturns.

For more information

Web site: www.aspenhomesco.com

Articles:

Aspen Homes' system first to include guarantee.
www.builtgreen.org/articles/0302_Aspen.htm
NAHB Energy Value Housing Award:
www.nahbrc.org/evha/2005-EVHA-book.pdf
Fort Collins Coloradoan:
www.aspenhomesco.com/media/2007%20March%20Coloradoan.pdf

Technical report:

DOE Building America Research Report, Performance Evaluations of Prototype House: 50%-60% Total Energy Savings Level. Task Order KAAX-3-33410-06. Prepared by IBACOS.
www.ibacos.com/pubs/Reports/KAAX-3-33410-06.A.4-performance%20Evaluations%2050%20to%2060_BA.pdf

ⁱThe guarantee specifies that annual heating costs will not exceed a specified amount, provided that the homeowner operates and maintains the heating system in a responsible manner. A copy of the heating consumption guarantee is available at: http://www.aspenhomesco.com/index.php?pr=Heating_Guarantee

ⁱⁱ For a detailed description of building design features, see the U.S. DOE / Building America report “Performance Evaluations of Prototype House: 50%-60% Total Energy Savings Level”, prepared by IBACOs.

ⁱⁱⁱ Aspen Homes participated in the EPA Indoor Air Quality Pilot program. The current Indoor Air Package specifications are available online at: http://www.energystar.gov/index.cfm?c=bldrs_lenders_raters.nh_iap

^iv See EVHA description at: http://www.aspenhomesco.com/media/2006_EVHA_Affordable.pdf

© 2002-2008 Southwest Energy Efficiency Project
2260 Baseline Rd. Suite 212, Boulder, CO 80302
(303) 447-0078 fax: (303) 786-8054 info@swenergy.org

Last Updated: 04/18/2008