Back9.8.10.3.(1)

ATTRIBUTION:

Functional Statement:

F21

To limit or accommodate dimensional change.

Objective:

OS3.1

 

APPLICATION:

Backfilling and grading around all exterior concrete steps that are cantilevered from foundation walls, in buildings to which Part 9 applies [see Sentence 1.3.3.3.(1) of Division A for application of Part 9].

INTENT:

To limit the probability of the transfer of uplift loads from freezing soil to the underside of stairs, which could lead to the failure of the stairs, anchorage system or foundation wall, which could lead to treads becoming unlevel, which could lead to persons falling, which could lead to harm to persons.

ATTRIBUTION:

Functional Statement:

F21

To limit or accommodate dimensional change.

Objective:

OS2.1

 

APPLICATION:

Backfilling and grading around all exterior concrete steps that are cantilevered from foundation walls, in buildings to which Part 9 applies [see Sentence 1.3.3.3.(1) of Division A for application of Part 9].

INTENT:

To limit the probability of the transfer of uplift loads from freezing soil to the underside of stairs, which could lead to the failure of the stairs, anchorage system or foundation wall, which could lead to an inability to support vertical building loads or lateral earth loads.
This is to limit the probability of compromised structural integrity, which could lead to:
  • structural failure, or
  • for environmental separators or elements supporting environmental separators, the displacement or failure of required environmental separation elements, which could lead to the deterioration of building elements.
This is to limit the probability of harm to persons.

ATTRIBUTION:

Functional Statement:

F21

To limit or accommodate dimensional change.

Objective:

OH1.1, OH1.2, OH1.3

 

APPLICATION:

Backfilling and grading around all exterior concrete steps that are cantilevered from foundation walls, in buildings to which Part 9 applies [see Sentence 1.3.3.3.(1) of Division A for application of Part 9].

INTENT:

Where the foundation wall encloses interior spaces, to limit the probability of the transfer of uplift loads from freezing soil to the underside of stairs, which could lead to the failure of the foundation wall at the point of stair attachment, which could lead to concrete or masonry cracking, which could lead to:
  • the ingress of moisture from the ground, or
  • compromised thermal performance of components intended to provide resistance to heat transfer.
This is to limit the probability of:
  • an inadequate control of the temperature of interior spaces, relative humidity, water ingress and accumulation,
  • the generation of pollutants from biological growth or from materials that become unstable on wetting, or
  • deterioration, which could lead to compromised integrity of elements supported or protected by foundations.
This is to limit the probability of:
  • negative effects on the air quality of indoor spaces,
  • the inadequate thermal comfort of persons, and
  • contact with moisture.
This is to limit the probability of harm to persons.