1) Except as provided in Articles 9.15.1.2. and 9.15.1.3., this Section applies to
a)concrete or unit masonry foundation walls and concrete footings not subject to surcharge
i)on stable soils with an allowable bearing pressure of 75 kPa or greater, and
ii)for buildings of wood-frame or masonry construction,
b) wood-frame foundation walls and wood or concrete footings not subject to surcharge
i) on stable soils with an allowable bearing pressure of 75 kPa or greater, and
ii) for buildings of wood-frame construction, and
c) flat insulating concrete form foundation walls and concrete footings not subject to surcharge (see A-9.15.1.1.(1)(c) and 9.20.1.1.(1)(b) in Appendix A)
i) on stable soils with an allowable bearing pressure of 75 kPa or greater, and
ii) for buildings of light-frame or flat insulating concrete form construction that are not more than 2 storeys in building height, with a maximum floor to floor height of 3 m, and containing only a single dwelling unit.
2) Foundations for applications other than as described in Sentence (1) shall be designed in accordance with Section 9.4.
1) Buildings erected on permafrost shall have foundations designed by a designer competent in this field in accordance with the appropriate requirements of Part 4.
1) Where the superstructure of a detached building conforms to the requirements of the deformation resistance test in
CAN/CSA-Z240.2.1, “Structural Requirements for Mobile
Homes,” the foundation shall be constructed in conformance with
a) the remainder of this Section, or
b)CSA Z240.10.1, “Site Preparation, Foundation, and Anchorage of Mobile Homes.”
1) Concrete shall conform to Section 9.3.
1) Concrete block shall conform to CSA A165.1,
“Concrete Block Masonry Units,” and shall have a
compressive strength over the average net cross-sectional area
of the block of not less than 15 MPa.
2) Mortar, grout, mortar joints,
corbelling and protection for unit masonry shall conform to
Section 9.20.
3) For concrete block foundation walls required to be reinforced,
a)mortar shall be Type S, conforming to CSA A179, “Mortar and Grout for Unit Masonry,”
b)grout shall be coarse, conforming to CSA A179, “Mortar and Grout for Unit Masonry,” and
c)placement of grout shall conform to CSA A371, “Masonry Construction for Buildings.”
1) Where pier-type foundations are used, the piers shall be designed to support the applied loads from the superstructure.
2) Where piers are used as a foundation system in a building of 1 storey in building height, the piers shall be installed to support the principal framing
members and shall be spaced not more than 3.5 m apart along the
framing, unless the piers and their footings are designed for
larger spacings.
3) The height of piers described in Sentence (2) shall not exceed 3 times their least dimension at the base of
the pier.
4) Where concrete block is used for piers described in
Sentence (2), they shall be laid with cores placed vertically,
and where the width of the building is 4.3 m or less, placed with their longest dimension at right angles to the longest dimension of the building.
1) Foundations of wood-frame construction shall conform to
a)CAN/CSA-S406, “Construction of Preserved Wood Foundations,” or
b)Part 4.
(See Appendix A.)1) Footings shall be provided under walls, pilasters,
columns, piers, fireplaces and chimneys that bear on soil or rock, except that footings may be omitted under piers or monolithic concrete walls if the
safe loadbearing capacity of the soil or rock is not exceeded.
1) Footings shall rest on undisturbed soil, rock or compacted granular fill.
2) Granular fill shall not contain pyritic material in a concentration that will damage the building to a degree that would adversely affect its stability or the performance
of assemblies. (See also Article 9.4.4.4. and A-9.4.4.4.(1) in Appendix A.)
1 ) Except as provided in Sentence 9.15.3.4.(2), the minimum footing width or area
requirements provided in Articles 9.15.3.4. to 9.15.3.7. shall apply to footings, where
a)the footings support
i)foundation walls of masonry, concrete, or flat insulating concrete form walls,
ii)above-ground walls of masonry, flat insulating concrete form walls or light wood-frame construction, and
iii)floors and roofs of light wood-frame construction,
b)the span of supported joists does not exceed 4.9 m, and
c)the specified live load on any floor supported by the footing does not exceed 2.4 kPa (see Table 4.1.5.3.).
2) Except as provided in Sentence 9.15.3.4.(2), where the span of the supported joists
exceeds 4.9 m, footings shall be designed in accordance with
Section 4.2.
3) Where the specified live load exceeds 2.4 kPa, footings shall be designed in accordance with Section 4.2.
1) Except as provided in Sentences (2) and (3) and in Articles 9.15.3.5. to 9.15.3.7., the minimum footing width or area shall comply with Table 9.15.3.4.
2) Where the supported joist span exceeds 4.9 m in
buildings with light wood-frame walls, floors and roofs, footing widths
shall be determined according to
a)Section 4.2., or
b)the following formula
where
| W | = minimum footing width, |
| w | = minimum width of footings supporting joists not exceeding 4.9 m, as defined by Table 9.15.3.4., |
| Σ sjs | = sum of the supported joist lengths on each storey whose load is transferred to the footing, and |
| storeys | = number of storeys supported by the footing. |
3) Where a foundation rests on gravel, sand or silt in which the water table level is less than the width of the footings below
the bearing surface,
a)the footing width for walls shall be not less than twice the width required by Sentences (1) and (2), and Articles 9.15.3.5. and 9.15.3.6., and
b) the footing area for columns shall be not less than twice the area required by Sentences (1) and (2) and Article 9.15.3.7.
| Table 9.15.3.4. Minimum Footing Sizes Forming Part of Sentence 9.15.3.4.(1) |
|||
| No. of Floors Supported | Minimum Width of Strip Footings, mm | Minimum Footing Area for Columns Spaced 3 m o.c., (1) m2 | |
|---|---|---|---|
| Supporting Exterior
Walls(2) | Supporting Interior
Walls(3) | ||
| 1 | 250 | 200 | 0.4 |
| 2 | 350 | 350 | 0.75 |
| 3 | 450 | 500 | 1.0 |
| Notes to Table 9.15.3.4. | |
|
|
|
| (1) | See Sentence 9.15.3.7.(1). |
| (2) | See Sentence 9.15.3.5.(1). |
| (3) | See Sentence 9.15.3.6.(1). |
1) The strip footing widths for exterior walls shown in
Table 9.15.3.4. shall be increased by
a)65 mm for each storey of masonry veneer over wood-frame construction supported by the foundation wall,
b)130 mm for each storey of masonry construction supported by the foundation wall, and
c) 150 mm for each storey of flat insulating concrete form wall construction supported by the foundation wall.
1) The minimum strip footing widths for interior
loadbearing masonry walls shown in Table 9.15.3.4. shall be increased by 100 mm for each storey of masonry construction supported by the footing.
2) Footings for interior non-loadbearing masonry walls shall be not less than 200 mm wide for walls up to 5.5 m high
and the width shall be increased by 100 mm for
each additional 2.7 m of height.
1) The footing area for column spacings other than shown
in Table 9.15.3.4. shall be adjusted in proportion to the
distance between columns.
1) Footing thickness shall be not less than the
greater of
a)100 mm, or
b)the width of the projection of the footing beyond the supported element.
1) Where step footings are used,
a)the vertical rise between horizontal portions shall not exceed 600 mm, and
b)the horizontal distance between risers shall not be less than 600 mm.
1) Insulating concrete form units shall be
manufactured of polystyrene conforming to the performance
requirements of CAN/ULC-S701, “Thermal Insulation,
Polystyrene, Boards and Pipe Covering,” for Type
2, 3 or 4 polystyrene.
1 ) Except as required in Sentence (2), the thickness of foundation walls made of unreinforced concrete block or solid
concrete and subject to lateral earth pressure
shall conform to Table 9.15.4.2.A. for walls not exceeding 2.5 m in unsupported height.
| Table 9.15.4.2.A Thickness of Solid Concrete and Unreinforced Concrete Block Foundation Walls Forming Part of Sentence 9.15.4.2.(1) |
|||
| Type of Foundation Wall | Minimum Wall Thickness, mm | Maximum Height of Finished Ground Above Basement Floor or Crawl Space Ground Cover, m | |
|---|---|---|---|
| Foundation Wall Laterally Unsupported at the Top(1) | Foundation Wall Laterally Supported at the Top(1) | ||
| Solid concrete, 15 MPa min. strength | 150 | 0.8 | 1.5 |
| 200 | 1.2 | 2.15 | |
| 250 | 1.4 | 2.3 | |
| 300 | 1.5 | 2.3 | |
| Solid concrete, 20 MPa min. strength | 150 | 0.8 | 1.8 |
| 200 | 1.2 | 2.3 | |
| 250 | 1.4 | 2.3 | |
| 300 | 1.5 | 2.3 | |
| Unreinforced Concrete Block | 140 | 0.6 | 0.8 |
| 190 | 0.9 | 1.2 | |
| 240 | 1.2 | 1.8 | |
| 290 | 1.4 | 2.2 | |
| Notes to Table 9.15.4.2.A | |
|
|
|
| (1) | See Article 9.15.4.3. |
2) The thickness of concrete in flat insulating
concrete form foundation walls shall be not less than the greater of
a)140 mm, or
b)the thickness of the concrete in the wall above.
3) Foundation walls made of flat insulating concrete form units shall be
laterally supported at the top and at the bottom.
4) Where average stable soils are encountered and wind loads on the exposed portion of the foundation are no greater than 0.70 kPa, the thickness and reinforcing of foundation walls made of reinforced concrete block and subject to lateral
earth pressure shall conform to Table 9.15.4.2.B and Sentences (5) to (10).
| Table 9.15.4.2.B Reinforced Concrete Block Foundation Walls Forming Part of Sentence 9.15.4.2.(4) |
|||||
| Minimum Wall Thickness, mm | Maximum Height of Finished Ground Above Basement Floor or Crawl Space Ground Cover, m |
Foundation Wall Laterally Unsupported at Top(1) | Foundation Wall Laterally Supported at Top(1) | ||
|---|---|---|---|---|---|
| Continuous Vertical Reinforcement | Continuous Vertical Reinforcement | ||||
| Minimum Bar Size | Maximum Bar Spacing, m | Minimum Bar Size | Maximum Bar Spacing, m | ||
| 190 | 1.0 | 25M | 1.2 | (2) | (2) |
| 1.2 | 25M | 1.2 | (2) | (2) | |
| 1.4 | 25M | 1.2 | 15M | 1.2 | |
| 1.6 | 25M | 0.8 | 15M | 1.2 | |
| 1.8 | 25M | 0.6 | 20M | 1.2 | |
| 2.0 | 25M | 0.4 | 20M | 1.2 | |
| 2.2 | (3) | (3) | 25M | 1.2 | |
| 2.4 | (3) | (3) | 25M | 1.2 | |
| 240 | 1.4 | 25M | 1.0 | (2) | (2) |
| 1.6 | 25M | 1.0 | (2) | (2) | |
| 1.8 | 25M | 0.8 | (2) | (2) | |
| 2.0 | 25M | 0.8 | 20M | 1.8 | |
| 2.2 | 25M | 0.8 | 25M | 1.8 | |
| 2.4 | 25M | 0.6 | 25M | 1.8 | |
| Notes to Table 9.15.4.2.B | |
|
|
|
| (1) | See Article 9.15.4.3. |
| (2) | No reinforcement required. |
| (3) | Design to Part 4. |
5) For concrete block walls required to be
reinforced, continuous vertical reinforcement shall
a)be provided at wall corners, wall ends, wall intersections, at changes in wall height, at the jambs of all openings and at movement joints,
b)extend from the top of the footing to the top of the foundation wall,
c)where foundation walls are unsupported at the top, have not less than 600 mm embedment into the footing, and
d)where foundation walls are laterally supported at the top, have not less than 50 mm embedment into the footing, if the floor slab does not provide lateral support at the wall base.
6) Where foundation walls are laterally unsupported, the footing shall be designed according to Part 4 to resist
overturning and sliding, if the maximum height of finished
ground above the basement floor or crawl space ground cover exceeds 1.50 m.
7) At the base of concrete block walls required to be
reinforced and where the height of finished ground above the
basement floor or crawl space ground cover exceeds 2.0 m, not less than one
15M intermediate vertical bar reinforcement shall be
installed midway between adjacent continuous vertical
reinforcement, and shall
a)extend to not less than 600 mm above the top of the footing, and
b)have not less than 50 mm embedment into the footing, if the floor slab does not provide lateral support at the wall base.
8) For concrete block walls required to be
reinforced, a continuous horizontal bond beam containing not
less than one 15M bar shall be installed
a)along the top of the wall,
b)at the sill and head of all openings greater than 1.20 m in width, and
c)at structurally connected floors.
9) In concrete block walls required to be reinforced,
all vertical bar reinforcement shall be installed along the
centre line of the wall.
10) In concrete block walls required to be reinforced,
ladder- or truss-type lateral reinforcement not less than
3.8 mm in diameter (no. 9 ASWG) shall be installed in the
bed joint of every second masonry course.
1) Sentences (2) to (4) pertain to lateral support for walls described in Sentence 9.15.4.2.(1).
2) Foundation walls shall be considered to be laterally supported at the top if
a)such walls support a solid masonry superstructure,
b)the floor joists are embedded in the top of the foundation walls, or
c)the floor system is anchored to the top of the foundation walls with anchor bolts, in which case the joists may run either parallel or perpendicular to the foundation walls.
3) Unless the wall around an opening is reinforced to
withstand earth pressure, the portion of the foundation wall beneath an opening shall be considered laterally unsupported if
a)the opening is more than 1.2 m wide, or
b)the total width of the openings in the foundation wall constitutes more than 25% of the length of the wall.
4) For the purposes of Sentence (3), the combined width of the openings shall be considered as a
single opening if the average width is greater than the width of
solid wall between them.
5) Flat insulating concrete form foundation walls shall be considered to be laterally supported at the top if
the floor joists are installed according to Article 9.20.17.5.
1) Flat insulating concrete form foundation walls shall be considered to be laterally supported at the bottom
where the foundation wall
a)supports backfill not more than 1.2 m in height,
b)is supported at the footing by a shear key and at the top by the ground floor framing, or
c)is doweled to the footing with not less than 15M bars spaced not more than 1.2 m o.c.
1) Horizontal reinforcement in flat insulating
concrete form foundation walls shall
a)consist of
i)one 10M bar placed not more than 300 mm from the top of the wall, and
ii)10M bars at 600 mm o.c., and
b)be located
i)in the inside half of the wall section, and
ii)with a minimum cover of 30 mm from the inside face of the concrete.
2) Vertical reinforcement in flat insulating concrete
form foundation walls shall be
a)provided in accordance with
i) Table 9.15.4.5.A for 140 mm walls,
ii) Table 9.15.4.5.B for 190 mm walls, and
iii) Table 9.15.4.5.C for 240 mm walls,
b)located in the inside half of the wall section with a minimum cover of 30 mm from the inside face of the concrete wall, and
c)where interrupted by wall openings, placed not more than 600 mm from each side of the openings.
3) Cold joints in flat insulating concrete form foundation walls shall be reinforced with no less than one 15M bar spaced at
not more than 600 mm o.c. and embedded 300 mm on both sides
of the joint.
4) Reinforcing around openings in flat insulating
concrete form foundation walls shall comply with Article 9.20.17.3. or 9.20.17.4.
| Table 9.15.4.5.A Vertical Reinforcement for 140 mm Flat Insulating Concrete Form Foundation Walls Forming Part of Sentence 9.15.4.5.(2) |
|||
| Max. Height of Finished
Ground Above Finished Basement Floor, m | Minimum Vertical Reinforcement | ||
|---|---|---|---|
| Maximum Unsupported Basement Wall Height | |||
| 2.44 m | 2.75 m | 3.0 m | |
| 1.35 | 10M at 400 mm o.c. | 10M at 400 mm o.c. | 10M at 400 mm o.c. |
| 1.6 | 10M at 400 mm o.c. | 10M at 380 mm o.c. | 10M at 380 mm o.c. |
| 2 | 10M at 380 mm o.c. | 10M at 380 mm o.c. | 10M at 380 mm o.c. |
| 2.2 | 10M at 250 mm o.c. | 10M at 250 mm o.c. | 10M at 250 mm o.c. |
| 2.35 | n/a | 10M at 250 mm o.c. | 10M at 250 mm o.c. |
| 2.6 | n/a | 10M at 250 mm o.c. | 10M at 250 mm o.c. |
| 3 | n/a | n/a | 15M at 250 mm o.c. |
| Table 9.15.4.5.B Vertical Reinforcement for 190 mm Flat Insulating Concrete Form Foundation Walls Forming Part of Sentence 9.15.4.5.(2) |
|||
| Max. Height of Finished
Ground Above Finished Basement Floor, m | Minimum Vertical Reinforcement | ||
|---|---|---|---|
| Maximum Unsupported Basement Wall Height | |||
| 2.44 m | 2.75 m | 3.0 m | |
| 2.2 | None required | 10M at 400 mm o.c. | 10M at 400 mm o.c. |
| 2.35 | n/a | 10M at 300 mm o.c. | 10M at 300 mm o.c. |
| 2.6 | n/a | 10M at 300 mm o.c. | 15M at 400 mm o.c. |
| 3.0 | n/a | n/a | 15M at 400 mm o.c. |
| Table 9.15.4.5.C Vertical Reinforcement for 240 mm Flat Insulating Concrete Form Foundation Walls Forming Part of Sentence 9.15.4.5.(2) |
|||
| Max. Height of Finished
Ground Above Finished Basement Floor, m | Minimum Vertical Reinforcement | ||
|---|---|---|---|
| Maximum Unsupported Basement Wall Height | |||
| 2.44 m | 2.75 m | 3.0 m | |
| 2.2 | None required | None required | None required |
| 2.6 | n/a | 15M at 400 mm o.c. | 15M at 400 mm o.c. |
| 3.0 | n/a | n/a | 15M at 400 mm o.c. |
1) Exterior foundation walls shall extend not less than 150 mm above finished ground level.
1) Where the top of a foundation wall is reduced in thickness to permit the installation of floor joists, the reduced section shall be not
more than 350 mm high and not less than 90 mm thick.
2) Where the top of a foundation wall is reduced in thickness to permit the installation of a masonry exterior facing, the reduced section
shall be
a)not less than 90 mm thick, and
b)tied to the facing material with metal ties conforming to Sentence 9.20.9.4.(3) spaced not more than
i)200 mm o.c. vertically, and
ii)900 mm o.c. horizontally.
3) The space between wall and facing described in Sentence (2) shall be filled with mortar.
1) Corbelling of masonry foundation walls supporting cavity walls shall conform to Article 9.20.12.2.
1) Crack control joints shall be provided in foundation walls more than 25 m long at intervals of not more than 15 m.
2) Joints required in Sentence (1) shall be designed to resist moisture penetration and shall be
keyed to prevent relative displacement of the wall portions
adjacent to the joint.
1) Interior masonry foundation walls not subject to lateral earth pressure
shall conform to Section 9.20.
1) Except as permitted in Sentence (2), foundation walls of hollow masonry units supporting floor joists shall be capped
with not less than 50 mm of solid masonry or concrete, or have
the top course filled with mortar or concrete.
2) Capping required in Sentence (1) need not be provided
a)in localities where termites are not known to occur,
b)when the joists are supported on a wood plate not less than 38 mm by 89 mm, and
c)when the siding overlaps the foundation wall not less than 12 mm.
1) Not less than 190 mm depth of solid masonry shall be
provided beneath beams supported on masonry.
2) Where the beam referred to in Sentence (1) is supported below the top of the foundation walls, the ends of such beams shall be protected from the weather.
1) Pilasters shall be provided under beams that frame
into unit masonry foundation walls 140 mm or less in thickness.
2) Pilasters required in Sentence (1) shall be not less than 90 mm by 290 mm and shall be bonded or
tied into the wall.
3) The top 200 mm of pilasters required in Sentence (1) shall be solid.
1) Concrete block foundation walls shall be parged on the exterior face
below ground level as required in Section 9.13.
1) Exterior surfaces of concrete block foundation walls above ground level shall have tooled joints, or shall be parged or
otherwise suitably finished.
1) All form ties shall be removed at least flush with the
concrete surface.