What training does an assessor actually have?
This varies more than people expect. Not every "energy assessor" has the same background, and the certification behind their name tells you a lot about what they're actually qualified to evaluate.
BPI Building Analyst (common in the US)
Issued by the Building Performance Institute. Certification requires passing a 100-question exam with a minimum 70% score, covering building science, combustion safety, and diagnostic testing. A BPI Building Analyst is trained specifically to identify health and safety issues (like backdrafting combustion appliances) alongside efficiency opportunities — not just insulation levels.
RESNET HERS Rater (common in the US, especially for new construction)
A more rigorous path: candidates complete two simulated ratings, a combustion safety testing session, and a written exam requiring 72% to pass. After certification, five probationary ratings must be completed within a year under a Rating Quality Assurance Provider before full certification. HERS Raters produce a numeric score (the HERS Index) that's directly comparable across homes — useful if you're also trying to understand your home's efficiency relative to a new build.
NRCan-registered Energy Advisor (Canada)
Required for an official EnerGuide rating (and was required for the Canada Greener Homes Grant, which is now closed). These advisors are registered directly with Natural Resources Canada and follow a standardized national protocol, so a rating from one advisor is comparable to a rating from any other, anywhere in the country.
Utility-run program certifications (Mass Save, CleanBC, HRSP)
Many utility rebate programs require their contractors to hold an underlying certification (often BPI or NRCan) plus program-specific training on that utility's exact rebate rules and paperwork. This is why an assessor certified for CleanBC isn't automatically qualified to do a Mass Save assessment, even though the underlying building science is identical.
What actually happens during the visit
Plan for 1.5 to 3 hours. The exact scope varies by program, but most assessments cover:
- Attic: insulation depth, type, and condition; air leaks around the hatch and penetrations
- Basement/crawlspace: insulation, moisture signs, rim joist condition
- Exterior walls: insulation level, sometimes checked via small test holes
- Heating and cooling system: age, fuel type, efficiency rating, general condition
- Water heater: age, type, efficiency
- Windows and doors: condition and count
- Combustion safety test: checks gas appliances for backdrafting or carbon monoxide risk — this is the health-and-safety piece most homeowners don't expect
- Blower door test (often optional): measures whole-home air leakage with a calibrated fan
Questions to ask before you book
- "What certification do you hold, and can you show me the credential?"
- "Does this assessment include a combustion safety test?"
- "Will you do a blower door test, or is that a separate add-on?"
- "Is this assessment free, or is there a cost if I don't proceed with recommended work?"
- "How long until I get the written report?"
- "Will the report show my exact rebate eligibility, or just general recommendations?"
Questions to ask during the visit
- "What's the single upgrade that would make the biggest difference in this house?"
- "Is there anything here that's a safety issue, not just an efficiency issue?"
- "What income tier do I qualify for, and what does that change about my rebate?"
- "If I only do one thing this year, what should it be?"
- "Are there any red flags with my current heating system I should know about before I get quotes?"
What the report should contain
- Current condition of insulation, air sealing, and mechanical systems
- Specific upgrade recommendations, in priority order
- Estimated rebate amount for each recommended upgrade
- Any health/safety flags (combustion issues, moisture, etc.)
- A list of program-approved contractors, if applicable
If your report is missing priority order or safety findings, ask why — a thorough assessment should include both, not just a list of possible upgrades.
Red flags during an assessment
- The assessor is also trying to sell you equipment on the spot. A legitimate assessment is independent of the sales process — if the person doing your audit is the same person pressuring you to sign a contract before they leave, get a second opinion.
- No combustion safety test on a home with gas appliances. This is a genuine safety check, not an upsell — skipping it is a real gap, not just a missed opportunity.
- Vague answers about certification. "I've been doing this for years" isn't the same as holding BPI, RESNET, or NRCan credentials.
- No written report, or a report that's just a sales brochure. You should get specific numbers for your specific home, not generic marketing material.