Ontario · Energy · checked September 28, 2026

Duct leakage and ductwork pressure testing in Guelph

If some rooms never get warm in winter or cool in summer, the problem is often the ductwork, not the furnace or air conditioner. In the Guelph area, 61% of households heat with a forced-air furnace, so duct losses affect many Guelph homes.

Get matched in Guelph → Duct leakage and airflow testing
A duct-testing fan on a basement floor connected by flexible duct to a furnace, a pressure gauge hanging from a joist

Typical cost

$200–$450

Forced-air furnaces

61%

Homes with ducts that can leak

Electric baseboards

Not published

Houses built before 1991

54%

Older houses usually leak more and have less insulation

How Guelph is built

Guelph's houses by when they were built Ten house shapes, one for each tenth of Guelph's 42,250 houses. Before 1961: 20%, 1961–1990: 34%, 1991–2000: 15%, 2001 or later: 32%. Older houses glow hotter.
  • Before 1961 20%
  • 1961–1990 34%
  • 1991–2000 15%
  • 2001 or later 32%
Each house stands for one in ten of Guelph's 42,250 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.

Who needs it in Guelph

In the Guelph area, 61% of households heat mainly with a forced-air furnace; natural gas is the main heating energy for 56% of households (Statistics Canada, 2023).

Of Guelph's 42,250 houses (single-detached, semi-detached, row houses and duplexes), 20% were built before 1961 and 54% before 1991, according to the 2021 Census. Ducts in older houses often run through unheated spaces with taped or unsealed joints, and supply runs to the far rooms are the first to suffer.

The same leaks cost you in summer when the ducts carry cooling: air from a central air conditioner or heat pump that escapes into an attic, garage or crawlspace is cooling you paid for, and leaky return ducts can pull in humid air. Sealing and balancing the ducts helps in both seasons, and it's worth doing before a new heat pump goes onto old ductwork.

What the test shows

  • Total duct leakage, as a share of the system's airflow, measured by pressure-testing the ductwork with a calibrated duct-pressurization fan.
  • Airflow at each register, which explains why one bedroom is always cold.
  • Whether sealing and balancing will fix comfort problems before you buy bigger equipment.

Duct leakage testing in detail.

What it costs

About $200–$450 (a September 2026 planning range; quotes vary). It isn't part of a standard EnerGuide evaluation, so ask for it when you book if comfort is your main complaint.

Great Lakes–St. Lawrence Southern Ontario and southern Quebec

What this means in Guelph’s climate

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.

  • 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. Ask: Ask for a room-by-room heat-loss calculation and a duct and airflow check before replacing your air conditioner or furnace.

What else homes in Guelph need →

Sources for this climate guide · checked October 26, 2026

Communities served

Area guides for the surrounding region, with every town and hamlet listed: Dufferin County area guide (Orangeville, Shelburne, Mono, Grand Valley and more); Wellington County area guide (Fergus, Elora, Mount Forest, Erin and more).

NRCan-licensed service organizations serving Guelph

A service organization is a company that Natural Resources Canada (NRCan) licenses to deliver EnerGuide evaluations; its registered energy advisors do the home visit. Duct leakage testing isn't part of a standard EnerGuide evaluation. Some of these organizations offer it, as do HVAC contractors with duct-testing equipment, so ask when you call.

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.

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

Programs in Guelph

Provincial · needs an evaluation 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 Open · deadline Provincial Home Renovation Savings — direct rebates (no assessment) Heat pumps up to $7,500 ($12,000 ground-source), solar with battery up to $10,000, plus attic, thermostat and appliance rebates — no assessment needed Open Federal National Heat Pump Rebate Announced October 8, 2026 and opening early 2027: up to $10,000 below the median income, $2,000 for other eligible homeowners Announced · opens 2027 Federal CMHC Eco Improvement premium refund A 25% energy-efficiency rebate on your CMHC mortgage insurance premium after $20,000 of energy renovations Open Municipal Guelph Greener Homes loan City of Guelph 0% interest loan (FCM Green Municipal Fund-supported), up to $50,000, repaid over 10 years with property taxes; no admin fee and no income threshold. Covers insulation, air sealing, windows and doors, air-source and cold-climate heat pumps, heat pump water heaters, solar PV and solar hot water. Pre- and post-retrofit energy audit reports are required. Loan funding is almost fully committed: the City is no longer taking loan applications, only waitlist sign-ups. Municipal Guelph Greener Homes low-income heat pump grant Grants of up to $15,000 (no repayment) for air-source heat pumps for eligible low-income owner-occupied households: property value assessment of $350,000 or less and household income under the City's limits (for example $47,090 for one person, $94,179 for four). A 50% deposit of project cost is required and grants are limited; the City says grant funding is still available.

Duct leakage testing in Guelph: common questions

How much does duct leakage testing cost in Guelph?

Plan on about $200–$450. It is usually a separate service from an EnerGuide evaluation.

Is duct cleaning the same thing?

No. Cleaning removes dust; it doesn't find or seal leaks. A leakage test measures where air is lost.

What is ductwork pressure testing?

The same thing as a duct leakage test: registers are sealed, a calibrated fan pressurizes the ducts, and the airflow needed to hold the test pressure shows how leaky they are.

Should I close vents in unused rooms?

Usually not. Closing registers raises duct pressure and can increase leakage elsewhere in the system.

Duct leakage testing near Guelph

Duct leakage testing in Cambridge16 kmDuct leakage testing in Kitchener21 kmDuct leakage testing in Waterloo26 kmDuct leakage testing in Milton29 kmDuct leakage testing in Burlington38 km All 70 cities →

Sources

Checked September 28, 2026. Census figures are for the municipality (Ontario); climate data is NRCan's HOT2000 station Mount Forest (64 km away).

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