It’s pretty darn obvious that the colder nights are coming. For most of us, that means nothing more than reluctantly starting up the wood stove, or setting a baseboard heater.

But for builders, cold weather means a bunch of considerations – or a stop to some kinds of construction entirely. Here’s a quick rundown on Code-enforceable temperature limits:

Concrete (9.3.1.9): When the air temperature is below 5°C, concrete shall be

• a) kept at a temperature of not less than 10°C or more than 25°C while being mixed and placed, and
• b) maintained at a temperature of not less than 10°C for 72 h after placing.

Mortar (9.20.14.1): Mortar and masonry shall be maintained at a temperature not below 5°C during installation and for not less than 48 h after installation.

Stucco: (9.28.6.1): 

• 1) The base for stucco shall be maintained above freezing.
• 2) Stucco shall be maintained at a temperature of not less than 10°C during application, and for not less than 48 h afterwards.

Drywall mud: (9.29.5.10): In cold weather, heat shall be provided to maintain a temperature not below 10°C for 48 h prior to taping and finishing and maintained for not less than 48 h thereafter.

Now, juuuuust in case you and your loved ones are arguing over what the correct indoor temperature should be, here’s what the National Building Code of Canada says: “At the outside winter design temperature, required heating facilities shall be capable of maintaining an indoor air temperature of not less than

• a) 22°C in all living spaces,
• b) 18°C in unfinished basements,
• c) 18°C in common service rooms, ancillary spaces and exits in houses with a secondary suite, and
• d) 15°C in heated crawl spaces.”