How Markham is built
- Before 1961 3%
- 1961–1990 38%
- 1991–2000 17%
- 2001 or later 43%
What an evaluation finds in Markham homes
Of Markham's 91,305 houses (single-detached, semi-detached, row houses and duplexes), 3% were built before 1961 and 40% before 1991, according to the 2021 Census. The typical Markham house dates from 1996–2000, and an evaluation is how you find out what that means for yours: the blower door measures air leakage, the advisor inspects the attic, walls, basement, windows and heating system, and the report ranks upgrades by what they'd save.
Markham gets about 3,863 heating degree-days a year, a measure of how much heating its climate needs, and its winter design temperature, the cold day heating systems are sized for, is −19.8°C. Those figures come from the climate data for Toronto Buttonville in HOT2000, the home-energy software Natural Resources Canada (NRCan) gives energy advisors. That's right around the middle of the 70 cities we cover. A moderate heating season with warm summers: fixes should cut heating bills and keep the house cool.
Markham summers are hot and humid, so the air sealing and insulation that cut heating bills also keep the house cooler, and a heat pump can do the cooling more efficiently than an old air conditioner.
In the Toronto area, 59% of households heat mainly with a forced-air furnace, 8% with a boiler and radiators, 5% with electric baseboards and 4% with a heat pump; natural gas is the main heating energy for 52% of households and electricity for 18% (Statistics Canada, 2023). The heating system on the report shapes the recommendations: a forced-air furnace invites a ducted heat pump, electric baseboards a ductless one.
What it costs in Markham
Typical Ontario prices are about $500–$700 for the initial EnerGuide evaluation and $200–$450 for the follow-up, plus HST where it applies. Windfall Ecology Centre charges $500 + HST for the initial evaluation and $250 + HST for the follow-up, Reep Green Solutions charges $540 and $406 with no HST, and City-backed programs in Ottawa and London quote $500–$700 as typical for the first visit. Only assessments from the seven HRSP-approved organizations qualify for the $600 Home Renovation Savings rebate, and none of the seven publishes a price.
Most providers quote the initial (pre-upgrade) and follow-up (post-upgrade) visits separately. Rebate programs that pay on measured improvement need both, so ask for the combined price.
How a home energy assessment (EnerGuide evaluation) works
- Initial evaluation, about 2–3 hours. The advisor measures and inspects the house and runs the blower door test.
- Report and EnerGuide rating. You get the home's energy rating in gigajoules per year and a list of recommended upgrades with estimated savings.
- Do the work. Most rebate programs only count upgrades done after the initial evaluation.
- Follow-up evaluation. A second visit measures the improvement, which is what most rebates pay on.
Great Lakes–St. Lawrence Southern Ontario and southern Quebec
Markham’s climate: Great Lakes–St. Lawrence
Cold winters and hot, humid summers: seal the attic, dry the basement, plan cooling.
This region has real winters and hot, humid summers, so bills come from both heating and cooling. Natural gas heats most Ontario homes, while most Quebec homes use low-cost electricity. An EnerGuide evaluation here should cover air sealing and the attic, cooling and dehumidification, and keeping the basement dry before insulating it.
In Markham: Markham has hot, humid summers, with about 18 days a year above 30°C and 20 at a humidex of 35 or more, and 10 cm or more of snow on the ground about 37 days a year. Plan cooling, dehumidification and attic air sealing together.
Seal air leaks and top up the attic
Air sealing is still the first retrofit. In the snowier Ottawa–Montreal–Sherbrooke belt, a leaky, under-insulated attic also causes ice dams.
Right-size cooling to control humidity
In humid summers, an oversized air conditioner or heat pump cools quickly but shuts off before removing moisture, leaving rooms clammy. A heat pump replacing the air conditioner also covers much of the heating.
Keep the basement dry before insulating
Basements can be about 20% of heat loss, but insulating a damp basement from the inside can rot the new wall. Flash floods have hit Toronto and Montreal repeatedly.
When to book: Book the evaluation in winter (December to February) for clear thermal scans, and start a 3-month radon test in fall. Check the basement after spring thaw or heavy rain, and line up cooling work before summer.
Everything homes in Markham need →
Sources for this climate guide · checked October 26, 2026
- National Building Code of Canada 2020, climate data (NRC)
- Canadian Climate Normals 1991–2020 (ECCC)
- Keeping the Heat In (NRCan)
- Air-Source Heat Pump Sizing and Selection Guide (NRCan)
- Heating and Cooling With a Heat Pump (NRCan)
- Heat pump basics (NRCan)
- Gas and heat pump hybrid systems (NRCan)
- Primary heating systems by household, Table 38-10-0286-01 (Statistics Canada)
- Electricity price comparison, April 2025 (Hydro-Québec)
- Canada's top weather stories of 2018 (ECCC)
- Canada's top weather stories of 2022 (ECCC)
- Canada's top weather stories of 2023 (ECCC)
- Canada's most impactful weather stories of 2024 (ECCC)
- Canada's top weather stories of 2025 (ECCC)
- 2024 Cross-Canada Survey of Radon Exposure
- Guide for Radon Measurements in Homes (Health Canada)
- Conditions for thermal scans, ASTM C1060 summary (Cx Associates)
Communities served
Markham's page covers the whole City of Markham, including Locust Hill and Unionville.
The organizations and professionals listed for Markham may or may not travel to every community, so ask when you call.
Area guide for the surrounding region, with every town and hamlet listed: Home energy audit in York Region (Newmarket, Aurora, Stouffville, Georgina and more).
NRCan-licensed service organizations serving Markham
A service organization is a company that Natural Resources Canada (NRCan) licenses to deliver EnerGuide evaluations; its registered energy advisors do the home visit. Every organization below is licensed by NRCan to deliver EnerGuide evaluations and lists Markham postal codes. Coverage is the share of Markham's urban postal areas each one lists.
Only assessments from the seven HRSP-approved organizations qualify for the $600 Home Renovation Savings rebate and its assessment-path upgrade rebates; each listing below says whether it's one of them.
- Acacia Engineering HRSP-approved: No
- Air Barrier Canada HRSP-approved: No
- All Season Inspection HRSP-approved: No Profile
- AmeriSpec HRSP-approved: Yes Profile
- BEST Energy and Sustainability HRSP-approved: No
- Clean Energy Solutions HRSP-approved: No
- ecoGEO Energy HRSP-approved: No
- Ecostep Energy Services HRSP-approved: No
- Energy Werx HRSP-approved: Yes Profile
- Enerhold Engineering Solutions HRSP-approved: No
- Enerhome Consulting HRSP-approved: No
- EnerQuality HRSP-approved: No
- EnerSolution HRSP-approved: No Profile
- Engreen Home HRSP-approved: No
- ER Energy Solutions HRSP-approved: No
- GETS Energy HRSP-approved: No
- Green Canada Home Advisors HRSP-approved: No Profile
- Green Think HRSP-approved: No
- Greenbrain HRSP-approved: Yes Profile
- Sensible Home Inspections HRSP-approved: No
- The Energuy HRSP-approved: Yes Profile
- Verdatech Energy Management and Consulting HRSP-approved: No
- Windfall Ecology Centre HRSP-approved: No Non-profit network Profile
- CoEfficient Building Science HRSP-approved: No
- EcoLogic Energy Advisors HRSP-approved: No
Rebates and financing an evaluation unlocks in Markham
Home energy audit in Markham: common questions
How much does a home energy audit cost in Markham?
Typical Ontario prices are about $500–$700 for the initial EnerGuide evaluation and $200–$450 for the follow-up, plus HST where it applies. Windfall Ecology Centre charges $500 + HST for the initial evaluation and $250 + HST for the follow-up, Reep Green Solutions charges $540 and $406 with no HST, and City-backed programs in Ottawa and London quote $500–$700 as typical for the first visit. Only assessments from the seven HRSP-approved organizations qualify for the $600 Home Renovation Savings rebate, and none of the seven publishes a price.
How many companies do EnerGuide evaluations in Markham?
NRCan's list of service organizations shows 28 licensed organizations with Markham postal codes (checked September 25, 2026). All seven organizations approved for Home Renovation Savings assessments are among them, and only their assessments qualify for its $600 rebate.
How long does an EnerGuide evaluation take?
The initial visit usually takes two to three hours, including the blower door test. The follow-up visit after upgrades is shorter.
Does an energy audit help with summer heat in Markham?
Yes. The advisor's upgrade list covers air sealing, attic insulation and windows, which slow summer heat gain as well as winter heat loss, and the evaluation's measurements are the starting point for sizing a heat pump that also cools.
Which rebates need an EnerGuide evaluation in Ontario?
Currently: Home Renovation Savings — Home Energy Assessment path (Up to $10,000 per home ($5,000 if heated with Enbridge gas), including $600 back on your two assessments, for insulation, windows, air sealing and more — if the follow-up assessment is done by December 31, 2026). Check the program page for current terms before you book.