COMMONWEALTH SUSTAINABILITY WORKS
GREEN BUILDING + SUSTAINABLE COMMUNITIES + STRATEGIC PLANNING

RESIDENTIAL ENERGY AUDITS, PLAN REVIEW, AND ENERGY MODELING

Learn how to make cost-effective improvements to your home or other small to mid-size building. Most can save 20% or more on energy bills with a very modest investment. For commercial and institutional audits, please contact us for an estimate.

Prices current as of December, 2009.
Learn about tax incentives at www.dsireusa.org.
For locations more than an hour's drive from Culpeper, a travel charge may apply.
Search for qualified auditors closer to home at BPI or RESNET.

Walk-Through Energy Audit – starting at $225
The base fee covers houses of 2500 or fewer conditioned square feet (conditioned basements are counted). Add $.05/sq foot for additional floor area beyond the 2500 mark. Combustion safety testing may be required. See below.

The walk-through audit is a 1.5 - 2.5 hour site visit to identify opportunities to lower energy costs and increase occupants’ comfort and health. This is a "building as a system" inspection to locate the most cost-effective improvements – not to sell a particular piece of equipment. I visually inspect air-sealing, HVAC, water heating, appliances, windows, lighting, and more. I encourage homeowners to join me on this tour so that I can show them first-hand the opportunities for improvement and answer their questions. Within two weeks I send a report of recommendations prioritized based on cost, impact, and timing. The report also includes notes on efficient practices around the home, suggestions for long-term planning to reduce energy use, and construction details for do-it-yourselfers.

To include a detailed utility bill analysis in your audit, send a spreadsheet listing two years of energy consumption (kilowatt hours of electricity, gallons of propane, etc. - not dollars) to andrew.grigsby@commonwealthsustainability.com. Please send this at least two days before the scheduled site visit.

Combustion Safety Testing - $75 for first appliance, $25 for subsequent appliances
For houses with naturally (up a chimney) vented oil or gas (natural or propane) heating or water heating, saftety testing is a required element of a home energy audit. Most energy improvements involve changes to the air infiltration rate (drafts) of the house, which affects the oxygen supply to and backdrafting potential of these "combustion appliances". The tests include measuring the combustion efficiency of the appliances, testing for backdrafting under various conditions, measuring the draft up the chimney, and measuring ambient carbon monoxide.

Whole House and Duct System Pressurization Tests – starting at $100 each (plus walk-through audit fee)
The overall draftiness – or “unintended infiltration” – of a house is measured by the blower door test. Drafts affect a home’s heating/cooling costs as much as any single other factor. The blower door also is used to locate these leaks and to discover the "air changes per hour" - a figure that greatly affects both energy use and occupant health. The $100 base fee covers houses of 2500 or fewer conditioned square feet (conditioned basements are counted). Add $.05/sq foot for additional floor area beyond the 2500 mark.

A duct blaster test measures the amount of air that a duct system loses to the outside of the house. If all of a home’s ductwork is installed within conditioned space this test may not be warranted. For homes with ducts in attics or vented crawlspaces, studies indicate that average leakage to the outside is greater than 15%. Leakage of greater than 30% is not uncommon. That's a lot of wasted energy - and money. For houses with more than one duct system to be tested, add $75 for each additional system.

These tests are powerful tools for identifying serious problems that may be hidden from a visual inspection – and may change priorities for remedial work. They also generate hard numbers that identify a house as performing well or poorly compared to other houses.

Plan Review for New Homes & Additions – starting at $200
An audit for an un-built home – so you can build it right the first time! Simply send a set of plans and I'll produce a detailed report with recommendations for you and your contractor. This base fee covers houses of 2500 or fewer conditioned square feet (conditioned basements are counted). Add $.05/sq foot for additional floor area beyond the 2500 mark.

Energy Modeling – starting at $200 plus other review/audit fees
Calculate the savings impact of different energy efficiency strategies for your house – before building! Using software approved by the US Dept. of Energy, we create a computer-based simulation that models the energy use of the house. After establishing the as-built or as-designed base case, I "test-drive" strategies such as upgrading windows, improving insulation, improving HVAC design, upgrading HVAC equipment, upgrading appliances, etc. With local utility rates programmed in, the software calculates the real dollar savings achieved by these options – helping homeowners and builders make the best decisions to lower the total cost of ownership.

The software also establishes the home's relative efficiency (HERS index). This index is required for energy efficient mortgages (EEMs) and to establish eligibility for the $2000 new home Federal tax credit - payable to the builder.

The $200 base fee covers houses of 2500 or fewer conditioned square feet (conditioned basements are counted). Add $.10/sq foot for additional floor area beyond the 2500 mark. For new houses, the modeling fee is added to the cost of a plan review. For existing houses, a walk-through audit and blower door and duct blaster tests are necessary first steps.