BUILDING STANDARDS
rd
222-3 AVE NORTH, SASKATOON, SK S7K 0J5
RESIDENTIAL HIGH FOUNDATIONS
Article 9.15.4.2 of the 2010 National Building Code limits the maximum height of an unreinforced 200 mm
(8”) concrete foundation wall to 3 m (10’). Table 9.15.4.2 permits up to 2.85 m (9’-4”) of backfill
against a 200 mm (8”) concrete foundation wall with 20MPa minimum strength.
Building Standards engaged the services of a structural engineer to provide engineered
designs for foundation walls exceeding 2.5m (8’-2”). The tables below are the result of that
report. It is recommended that foundation walls exceeding 2.5 m (8’-2”) within the City of
Saskatoon be reinforced as per the tables below. The foundation walls must be laterally
supported at the top and bottom.
Table 1.1
Vertical Reinforcing for
> 8’-4” and <= 9’-0” high
Foundation wall
Final
Grade
Height(ft)
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
8.0
8.5
Size of
Vertical Bars
Bar Spacing
(inches)
10M
10M
10M
10M
10M
10M
10M
15M
15M
15M
48
48
32
24
20
16
12
24
20
18
Design Assumptions
1. 20 MPa, HS (Type 50)
2. Reinforcement to be on inside face with a minimum
cover of 25 mm (1”) and a maximum cover of 50
mm (2”).
3. Basement wall height is measured from the top of
the concrete floor to the underside of floor joists.
4. Final grade height is measure from the top of the
basement floor to the maximum grade adjacent to
the foundation wall.
5. 15M bar may be substituted for 10M bar and the
spacing may be doubled up to 1.2m (48” o.c.).
6. Horizontal reinforcement is to be minimum 2-10M
top, mid-height and bottom.
Vertical
reinforcement on
inside face only
Table 1.2
Vertical Reinforcing for
> 9’-0” and <= 10’-0” high
foundation wall
Final
Size of
Bar Spacing
Grade
Vertical Bars
(inches)
Height(ft)
4.0
10M
48
4.5
10M
32
5.0
10M
24
5.5
10M
20
6.0
10M
16
6.5
10M
12
7.0
15M
22
7.5
15M
18
8.0
15M
16
8.5
15M
12
Updated 14/04/2015
Final Grade
Basement
wall height
8” concrete
foundation wall
Final grade
height