Alberta · Energy · checked September 28, 2026

Blower door testing in Lethbridge

A blower door test measures how leaky a house is and shows where the leaks are. In Lethbridge, with about 4,274 heating degree-days a year, every leak runs up the heating bill for most of the year.

Get matched in Lethbridge → The blower door test, step by step
A red blower-door panel with a large fan fitted into the front doorway of a brick bungalow, a pressure gauge on a stool inside

Cost

Included in an evaluation

Evaluation price

Expect $400+

Licensed organizations

21

Companies NRCan licenses to do EnerGuide evaluations

Houses built before 1961

19%

Older houses usually leak more and have less insulation

How Lethbridge is built

Lethbridge's houses by when they were built Ten house shapes, one for each tenth of Lethbridge's 33,945 houses. Before 1961: 19%, 1961–1990: 35%, 1991–2000: 11%, 2001 or later: 35%. Older houses glow hotter.
  • Before 1961 19%
  • 1961–1990 35%
  • 1991–2000 11%
  • 2001 or later 35%
Each house stands for one in ten of Lethbridge's 33,945 houses (single-detached, semi-detached, row and duplex), drawn by when it was built. The glow shows the usual pattern: older houses tend to be leakier and less insulated. More snow in the drawing means more heating degree-days: a longer, colder heating season. Sources: Statistics Canada 2021 Census (table 98-10-0233-01), NRCan HOT2000 climate data.

Why air leakage matters in Lethbridge

Lethbridge gets about 4,274 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 −26.1°C. Those figures come from the climate data for Lethbridge in HOT2000, the home-energy software Natural Resources Canada (NRCan) gives energy advisors. That's about 9% more heating demand than the middle of the 70 cities we cover. A long heating season: air sealing and insulation pay back well, and every leak costs money for months.

Lethbridge also gets hot spells and heat waves, so plan how the house will stay cool: air sealing, attic insulation and shading help, and a heat pump adds efficient cooling. Wildfire smoke reaches Lethbridge in some summers. The Government of Canada's advice is to keep windows and doors closed, limit exhaust fans and use the best filter your system can handle, so ask the advisor what your furnace or HRV can take.

Of Lethbridge's 33,945 houses (single-detached, semi-detached, row houses and duplexes), 19% were built before 1961 and 54% before 1991, according to the 2021 Census. Older houses usually test leakier than newer ones, and an EnerGuide report compares your result with homes of the same era, so you can see whether your house is typical or a problem.

After you seal: two checks

  • Combustion safety. In the Lethbridge area, the main heating energy is natural gas for 81% of households. A tighter house changes how fuel-burning appliances vent, so the spillage check should be repeated after serious air sealing. Combustion safety testing in Lethbridge
  • Radon. Sealing shifts the pressure balance between the house and the soil. Health Canada's 2012 survey found 9% of 111 homes tested in the Chinook Regional Health Authority health region above the guideline. The larger 2024 Cross-Canada survey reports 16.8% (1 in 6) of houses at or above the guideline for the Lethbridge, AB (Lethbridge CMA) metro area. Test before and after big air-sealing jobs. Radon testing in Lethbridge

What it costs in Lethbridge

A blower door test is part of every EnerGuide evaluation rather than a separate purchase. There's no provincial rebate or price list; the City of Edmonton's guidance is to expect more than $400 and to get two or three quotes.

How the test works

  • A calibrated fan is fitted into an exterior door and pulls air out until the house is at 50 pascals, the standard test pressure.
  • The result is air changes per hour at 50 Pa (ACH50): how many times an hour the whole volume of air would leak out and be replaced at that pressure.
  • While the fan runs, you and the advisor walk the house and feel for leaks at the attic hatch, rim joists, pot lights, trim and plumbing and wiring penetrations.
  • A second test after the work shows what changed, and it is what most rebates pay on.

The blower door test in detail.

Prairies Alberta, Saskatchewan and Manitoba

What this means in Lethbridge’s climate

Long, very cold, very dry winters: air sealing, radon testing and humidity balance lead.

Why it matters here: Measures leakage and, with a thermal scan, pinpoints attic bypasses and rim joist and window leaks.

Best timing: Any season; most revealing with a thermal scan on a cold, calm day.

  • Seal the top and bottom of the house. In deep cold, warm air rises and escapes through attic leaks while cold air is pulled in down low. Sealing both saves heat and helps prevent attic frost and ice dams. Ask: Ask the registered energy advisor to find attic bypasses, rim joist gaps and basement penetrations during the blower door test.
  • Insulate the basement and rim joists. Basements can account for about 20% of a home's heat loss. Check for cracks and water entry first; Manitoba's clay soils cracked some foundations during the 2021 drought. Ask: Ask whether the basement is dry enough to insulate from inside, and how much air leaks at the rim joist.

What else homes in Lethbridge need →

Sources for this climate guide · checked October 26, 2026

NRCan-licensed service organizations serving Lethbridge

A service organization is a company that Natural Resources Canada (NRCan) licenses to deliver EnerGuide evaluations; its registered energy advisors do the home visit. A blower door test is part of every EnerGuide evaluation, so any organization below can do one in Lethbridge. Ask to walk the house with the advisor while the fan runs.

Source: NRCan list of licensed service organizations, checked September 28, 2026. Call to confirm your street is covered and ask about wait times.

Programs that include a blower door test in Lethbridge

Provincial · needs an evaluation Clean Energy Improvement Program (Alberta) Property-tax financing in 27 Alberta municipalities, with an EnerGuide evaluation required; Calgary is closed until winter 2026/27 and Edmonton is waitlisting Open · deadline

Blower door test in Lethbridge: common questions

Where can I get a blower door test in Lethbridge?

Book an EnerGuide evaluation with any of the 21 NRCan-licensed organizations serving Lethbridge; the blower door test is part of every evaluation.

How much does a blower door test cost in Lethbridge?

It is included in an EnerGuide evaluation. There's no provincial rebate or price list; the City of Edmonton's guidance is to expect more than $400 and to get two or three quotes.

What is a good blower door result?

Lower is better. Your EnerGuide report compares your air changes per hour at 50 Pa with homes of the same era, which is more useful than a single target number.

Does air sealing affect radon?

It can. Tightening a house changes the pressure difference with the soil, so test for radon before and after major air sealing.

Blower door test near Lethbridge

Blower door test in Calgary177 kmBlower door test in Red Deer296 kmBlower door test in Sherwood Park427 kmBlower door test in Edmonton433 kmBlower door test in Kelowna475 km All 70 cities →

Sources

Checked September 28, 2026. Census figures are for the municipality (Alberta); climate data is NRCan's HOT2000 station Lethbridge (4 km away).

Get matched with a registered advisor in Lethbridge

Tell us your postal code and what you’re planning. We’ll connect you with one licensed service organization serving your area. No spam, no shared lead lists.

By submitting you agree we may share your request with one registered service organization serving your area. Participating advisors pay us a referral fee — you pay nothing, and it never affects the directory. See our privacy note.