Energy audit
Home Energy Audit Cost Calculator
Cost calculator for residential energy audits across all tiers, with utility-subsidy adjustment.
Quick answer: walkthrough $100–$350, standard BPI $250–$650, HERS Index $450–$900, full $600–$1,400. Many utilities offer free or 50% subsidized standard audits — check Mass Save, ConEd, Energy Trust of Oregon, PG&E, Xcel before paying.
Audit cost · standard · Massachusetts
$224
range $132 – $343 after subsidy
Why get an audit
- · Pre/post blower-door diagnostics let you measure air-sealing work, not just visually confirm it.
- · Required by DOE HOMES rebate program for measured-savings tier (up to $8,000 for low-income).
- · IR camera identifies insulation voids, thermal bridges, and air leaks invisible to the eye.
- · Combustion safety check on gas appliances catches CO and back-drafting risks.
- · HERS Index rating sticks with the home — required by some loan/refi products and ENERGY STAR home certification.
Why audit before any major upgrade
An energy audit is diagnostic — it tells you what you actually need before you spend $20,000 on equipment. A 2-hour BPI audit with blower door, IR camera, and combustion safety check can identify the real comfort problems (often it’s air leakage, not the furnace), reveal hidden hazards (CO back-drafting, knob-and-tube wiring), and produce a prioritized list of upgrades by ROI. For DOE HOMES rebate eligibility, a HERS Index pre/post is required.
Frequently asked questions
How much does a home energy audit cost?
Walkthrough audit: $100–$350. Standard BPI audit with blower door + IR camera: $250–$650. HERS Index rating: $450–$900. Full audit (HERS + duct blaster + combustion safety + written report): $600–$1,400. Many utilities offer the standard tier free or heavily subsidized — check Mass Save, ConEd, Energy Trust of Oregon, PG&E, Xcel, ComEd before paying.
BPI vs RESNET HERS — what is the difference?
BPI (Building Performance Institute) certifies contractors to diagnose comfort, durability, and safety issues. Best for "I have a comfort problem, what is wrong" use cases. RESNET HERS (Home Energy Rating System) is a numeric score (lower = better, new construction targets HERS 60) used by ENERGY STAR homes and required for some loan products. Both use the same blower-door + duct-blaster equipment.
Is an audit required for the DOE HOMES rebate?
Yes for the measured-savings track (up to $8,000 for low-income, $4,000 for moderate). The modeled-savings track requires a HERS rater run a HERS Index pre and post project to verify the projected 20-35%+ energy reduction. Walkthrough audits don't qualify.
What does an audit actually measure?
Blower-door test (CFM50 leakage, ACH50 ratio). Duct blaster test (CFM25 leakage to outside). Infrared camera scan (insulation voids, thermal bridges). Combustion safety test (CO detection, depressurization risk). Equipment inspection (furnace efficiency, water heater age/UEF). Lighting audit (kWh from CFLs/LEDs/incandescents). Recommendations prioritized by ROI.