How Lévis is built
- Before 1961 14%
- 1961–1990 46%
- 1991–2000 13%
- 2001 or later 26%
Why mold shows up in Lévis homes
Lévis gets about 4,754 heating degree-days a year and has a winter design temperature of −24.8°C, according to NRCan's HOT2000 climate data for Ste-Foy. On cold days, exterior corners, closets on outside walls and window frames get cold enough for condensation, which is where mold usually starts in Lévis houses.
Of Lévis's 45,165 houses (single-detached, semi-detached, row houses and duplexes), 14% were built before 1961 and 60% before 1991, according to the 2021 Census. Older basements without a moisture barrier and houses that were air-sealed without adding ventilation are common trouble spots.
When sampling is worth it
- You smell mustiness but can't find the source.
- After a leak or flood, to check that cleanup worked.
- Before buying an older house with signs of past water damage.
If you can see mould, you usually don't need a test to know it's there; you need to fix the moisture and clean it up properly.
Quebec has a voluntary standard for handling mould in homes (BNQ 3009-600, 2020); no province has a mandatory residential mould standard.
Choosing a tester and lab
Ask any Lévis tester which lab analyzes their samples, and look for one accredited under AIHA's EMLAP program for environmental microbiology. Pair sampling with a ventilation and humidity assessment, which finds the cause.
Ventilation and humidity assessments in Lévis · Our mold and indoor air quality guide
Mold and air quality testing in Lévis: common questions
How much does mold testing cost in Lévis?
Plan on about $300–$600 for a typical sampling visit (a September 2026 planning range); lab fees for extra samples add to that.
Do I need a test if I can see mould?
Usually not. Visible mould needs cleanup and a fix for the moisture source. Testing helps most when you suspect mould you can't see.
Is there a legal mould limit for homes in Canada?
No. Health Canada sets no numerical limit; its guidance is to control moisture and clean up mould. Quebec has a voluntary handling standard.