The 2015 National Building Code of Canada (NBC) is published by NRC and developed by the Canadian Commission on Building and Fire Codes (CCBFC). It contains technical provisions for the design and construction of new buildings. It also applies to the transformation, change of use and demolition of existing buildings. More than 360 technical changes have been incorporated in this new edition.
According to Section 188.8.131.52 of the NBC-MQ, compressive strength and percentage of entrained air are characteristics that affect the ability of a concrete to resist not only the loads imposed on it, but also freeze cycles.
Concrete for foundation walls, beams, columns, posts and fireplaces shall have a minimum compressive strength of 15 MPA.
Have a minimum compressive strength of 20 MPA for floors other than garage and carport floors.
Finally, for stoops, garage and carport floors, the concrete must have a minimum strength of 32 MPA and contain 5 to 8% entrained air.
The various problems encountered over the past 25 years, both in foundation walls and exterior slabs, have shown us that the minimum requirements of the Code are not sufficient to avoid these problems. That’s why we’re making these recommendations.
|CNB-MQ 184.108.40.206||APCHQ recommendations|
|MPA resistance||of entrained air||MPA resistance||of entrained air|
|Soles||15||20||3 to 6% of the total|
|Foundation walls||15||20||5 to 8% of the total|
|Garage slabs and elements subject to the freeze/thaw cycle||32||5 to 8% of the total||32||5 to 8% of the total|