British Columbia · Energy · checked September 28, 2026

Ventilation and humidity assessments in Nanaimo

Condensation on windows, musty basements and stuffy bedrooms are ventilation and humidity problems, and they're easy to confuse with insulation problems. A ventilation assessment measures which one you have.

Get matched in Nanaimo → The ventilation and humidity assessment
A heat recovery ventilator on a basement wall with four insulated ducts running up between the joists

Cost

Part of an evaluation

Houses built since 2001

28%

Houses built before 1961

15%

Winter design temperature

−3.2°C

How Nanaimo is built

Nanaimo's houses by when they were built Ten house shapes, one for each tenth of Nanaimo's 33,520 houses. Before 1961: 15%, 1961–1990: 40%, 1991–2000: 18%, 2001 or later: 28%. Older houses glow hotter.
  • Before 1961 15%
  • 1961–1990 40%
  • 1991–2000 18%
  • 2001 or later 28%
Each house stands for one in ten of Nanaimo's 33,520 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. Snowfall scales with heating degree-days. Sources: Statistics Canada 2021 Census (table 98-10-0233-01), NRCan HOT2000 climate data.

Why Nanaimo homes get humidity problems

Nanaimo gets about 2,939 heating degree-days a year and has a winter design temperature of −3.2°C, according to NRCan's HOT2000 climate data for Comox, the closest comparable location in that data set (87 km away). Mild, damp winters mean indoor humidity rarely has a chance to dry out on its own, so fans that actually vent outside matter.

Of Nanaimo's 33,520 houses (single-detached, semi-detached, row houses and duplexes), 15% were built before 1961 and 54% before 1991, according to the 2021 Census. Newer houses (28% of Nanaimo's were built since 2001) are tight and usually have an HRV or ERV that needs balancing and cleaning. Older houses that get air-sealed can lose the accidental ventilation they used to rely on.

What the assessment measures

  • Relative humidity in living areas and the basement.
  • Actual airflow from bath and kitchen fans, and whether they vent outside rather than into the attic.
  • How much fresh air the house gets, and whether an HRV or ERV is balanced.

The ventilation and humidity assessment in detail.

Related tests in Nanaimo

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NRCan-licensed service organizations serving Nanaimo

Advisors assess ventilation and humidity as part of an evaluation and check that exhaust fans actually vent outside. Sizing an HRV or ERV may be extra.

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 Nanaimo

Provincial · needs an evaluation BC Home Energy Improvement Bonus $20 for every percentage-point your home improves — $750 minimum, $2,000 maximum — or $300 for any two upgrades Open

Ventilation and humidity assessment in Nanaimo: common questions

HRV or ERV?

Both bring in fresh air and recover heat. An ERV also transfers some moisture, which helps keep very dry winter air from getting drier; an HRV suits houses that tend to run humid.

Why did condensation appear after we got new windows?

Tighter windows cut accidental air leakage, so humidity builds up. The fix is usually controlled ventilation, not leakier windows.

Is a ventilation assessment part of an EnerGuide evaluation in Nanaimo?

Advisors assess ventilation and humidity during the evaluation; HRV or ERV sizing may be an extra service.

Ventilation and humidity assessment near Nanaimo

Ventilation and humidity assessment in Richmond64 kmVentilation and humidity assessment in Vancouver65 kmVentilation and humidity assessment in Delta73 kmVentilation and humidity assessment in Burnaby74 kmVentilation and humidity assessment in Coquitlam83 km All 70 cities →

Sources

Checked September 28, 2026. Census figures are for the municipality (British Columbia); climate data is NRCan's HOT2000 station Comox (87 km away).

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