SB-11 — Construction of Farm Buildings

Section 1 General

1.1. Scope

1.1.1. Application

1. This Section applies to farm buildings of low human occupancy.

1.1.2. Construction Requirements

1. The construction of farm buildings of low human occupancy shall, subject to Article 2.1.3.5. in Division B of the Building Code, conform to the requirements of Part 9 of Division B of the Building Code except as provided in this Section.

1.2. Lumber

1.2.1. Lumber Requirements

1. Except as permitted by Article 1.2.2. , lumber shall conform to appropriate requirements in Subsection 9.3.2. of Division B of the Building Code.

1.2.2. Ungraded Lumber

1. Ungraded lumber may be used for wood posts, joists, rafters, lintels, beams and wall studs in a farm building of low human occupancy of not more than one storey in building height.

2. Ungraded lumber means lumber that has not been grade-stamped to indicate its grade, as determined by the NLGA "Standard Grading Rules for Canadian Lumber (Interpretation Included)", but that meets the following visual attributes:

1. it is rough sawn to full nominal size,

2. it has no evidence of decay,

3. it has no tight knots that exceed 25 percent of the cross section and that are spaced closer than 150 mm on centres,

4. it has no loose knots or holes that exceed 25 percent of the cross section and that are spaced closer than 600 mm on centres,

5. it has the slope of grain not exceeding 1 (vertical) in 4 (horizontal), and

6. it is free of excessive warp.

1.3. Structural Requirements

1.3.1. Structural Design

1. Except as provided in Articles 1.3.2. to 1.3.4. , wood posts, joists, rafters, lintels, beams and wall studs shall be designed in conformance with Section 9.4. of Division B of the Building Code.

1.3.2. Posts

1. In a farm building of low human occupancy, the size of wood posts shall conform to Tables 1.3.2.A. to 1.3.2.J. for the loads shown in the Tables.

1.3.3. Spans

1. In a farm building of low human occupancy, the spans of wood joists, rafters, lintels and beams shall conform to the spans shown in Tables 1.3.3.K. to 1.3.3.T. for the loads shown in the Tables.

1.3.4. Stud Size and Spacing

1. In a farm building of low human occupancy, the size and spacing of wood studs shall conform to Tables 1.3.4.U. to 1.3.4.W. for the loads shown in the Tables.

Table 1.3.2.A. Post Sizes for Diaphragm-Braced Farm Buildings of Low Human Occupancy

Forming Part of Sentence 1.3.2.(1)

Legend - Post Sizes: A = 89 mm x 140 mm · B = 140 mm x 140 mm · C = 140 mm x 184 mm · D = 184 mm x 184 mm

Notes to Table 1.3.2.A.:

1. Designs are based on load combinations of total roof load and wind load acting at the same time on a closed building.
2. Posts shall be oriented with the long dimension parallel to the building width.
3. Bracing systems shall be specified by a competent designer.
4. Posts shall be situated on footings and shall be anchored to prevent wind uplift.
5. Posts shall be constrained against lateral movement at ground level and at the footing. Concrete floor, splash-rail and uplift anchor help to meet this condition.
6. Post designs are based on partial fixity condition due to embedment in soil.
7. Footing excavations should be backfilled with parent material unless otherwise specified by a competent designer.

Table 1.3.2.B. Post Sizes for Diaphragm-Braced Farm Buildings of Low Human Occupancy

Forming Part of Sentence 1.3.2.(1)

Legend - Post Sizes: A = 89 mm x 140 mm · B = 140 mm x 140 mm · C = 140 mm x 184 mm · D = 184 mm x 184 mm

Notes to Table 1.3.2.B.:

1. Designs are based on load combinations of total roof load and wind load acting at the same time on a closed building.
2. Posts shall be oriented with the long dimension parallel to the building width.
3. Bracing systems shall be specified by a competent designer.
4. Posts shall be situated on footings and shall be anchored to prevent wind uplift.
5. Posts shall be constrained against lateral movement at ground level and at the footing. Concrete floor, splash-rail and uplift anchor help to meet this condition.
6. Post designs are based on partial fixity condition due to embedment in soil.
7. Footing excavations should be backfilled with parent material unless otherwise specified by a competent designer.

Table 1.3.2.C. Post Sizes for Knee-Braced Farm Buildings of Low Human Occupancy

Forming Part of Sentence 1.3.2.(1)

Legend - Post Sizes: A = 89 mm x 140 mm · B = 140 mm x 140 mm · C = 140 mm x 184 mm · D = 184 mm x 184 mm

Notes to Table 1.3.2.C.:

1. Designs are based on load combinations of total roof load and wind load acting at the same time on a closed building.
2. Posts shall be oriented with the long dimension parallel to the building width.
3. Bracing systems shall be specified by a competent designer.
4. Posts shall be situated on footings and shall be anchored to prevent wind uplift.
5. Posts shall be constrained against lateral movement at ground level and at the footing. Concrete floor, splash-rail and uplift anchor help to meet this condition.
6. Post designs are based on partial fixity condition due to embedment in soil.
7. Footing excavations should be backfilled with parent material unless otherwise specified by a competent designer.

Table 1.3.2.D. Post Sizes for Knee-Braced Farm Buildings of Low Human Occupancy

Forming Part of Sentence 1.3.2.(1)

Legend - Post Sizes: A = 89 mm x 140 mm · B = 140 mm x 140 mm · C = 140 mm x 184 mm · D = 184 mm x 184 mm

Notes to Table 1.3.2.D.:

1. Designs are based on load combinations of total roof load and wind load acting at the same time on a closed building.
2. Posts shall be oriented with the long dimension parallel to the building width.
3. Bracing systems shall be specified by a competent designer.
4. Posts shall be situated on footings and shall be anchored to prevent wind uplift.
5. Posts shall be constrained against lateral movement at ground level and at the footing. Concrete floor, splash-rail and uplift anchor help to meet this condition.
6. Post designs are based on partial fixity condition due to embedment in soil.
7. Footing excavations should be backfilled with parent material unless otherwise specified by a competent designer.

Table 1.3.2.E. Post Sizes for Diaphragm-Braced Farm Buildings of Low Human Occupancy

Forming Part of Sentence 1.3.2.(1)

Legend - Post Sizes: A = 101.6 mm x 152.4 mm · B = 152.4 mm x 152.4 mm · C = 152.4 mm x 203.2 mm · D = 203.2 mm x 203.2 mm

Notes to Table 1.3.2.E.:

1. Designs are based on load combinations of total roof load and wind load acting at the same time on a closed building.
2. Posts shall be oriented with the long dimension parallel to the building width.
3. Bracing systems shall be specified by a competent designer.
4. Posts shall be situated on footings and shall be anchored to prevent wind uplift.
5. Posts shall be constrained against lateral movement at ground level and at the footing. Concrete floor, splash-rail and uplift anchor help to meet this condition.
6. Post designs are based on partial fixity condition due to embedment in soil.
7. Footing excavations should be backfilled with parent material unless otherwise specified by a competent designer.

Table 1.3.2.F. Post Sizes for Diaphragm-Braced Farm Buildings of Low Human Occupancy

Forming Part of Sentence 1.3.2.(1)

Legend - Post Sizes: A = 101.6 mm x 152.4 mm · B = 152.4 mm x 152.4 mm · C = 152.4 mm x 203.2 mm · D = 203.2 mm x 203.2 mm

Notes to Table 1.3.2.F.:

1. Designs are based on load combinations of total roof load and wind load acting at the same time on a closed building.
2. Posts shall be oriented with the long dimension parallel to the building width.
3. Bracing systems shall be specified by a competent designer.
4. Posts shall be situated on footings and shall be anchored to prevent wind uplift.
5. Posts shall be constrained against lateral movement at ground level and at the footing. Concrete floor, splash-rail and uplift anchor help to meet this condition.
6. Post designs are based on partial fixity condition due to embedment in soil.
7. Footing excavations should be backfilled with parent material unless otherwise specified by a competent designer.

Table 1.3.2.G. Post Sizes for Knee-Braced Farm Buildings of Low Human Occupancy

Forming Part of Sentence 1.3.2.(1)

Legend - Post Sizes: A = 101.6 mm x 152.4 mm · B = 152.4 mm x 152.4 mm · C = 152.4 mm x 203.2 mm · D = 203.2 mm x 203.2 mm

Notes to Table 1.3.2.G.:

1. Designs are based on load combinations of total roof load and wind load acting at the same time on a closed building.
2. Posts shall be oriented with the long dimension parallel to the building width.
3. Bracing systems shall be specified by a competent designer.
4. Posts shall be situated on footings and shall be anchored to prevent wind uplift.
5. Posts shall be constrained against lateral movement at ground level and at the footing. Concrete floor, splash-rail and uplift anchor help to meet this condition.
6. Post designs are based on partial fixity condition due to embedment in soil.
7. Footing excavations should be backfilled with parent material unless otherwise specified by a competent designer.

Table 1.3.2.H. Post Sizes for Knee-Braced Farm Buildings of Low Human Occupancy

Forming Part of Sentence 1.3.2.(1)

Legend - Post Sizes: A = 101.6 mm x 152.4 mm · B = 152.4 mm x 152.4 mm · C = 152.4 mm x 203.2 mm · D = 203.2 mm x 203.2 mm

Notes to Table 1.3.2.H.:

1. Designs are based on load combinations of total roof load and wind load acting at the same time on a closed building.
2. Posts shall be oriented with the long dimension parallel to the building width.
3. Bracing systems shall be specified by a competent designer.
4. Posts shall be situated on footings and shall be anchored to prevent wind uplift.
5. Posts shall be constrained against lateral movement at ground level and at the footing. Concrete floor, splash-rail and uplift anchor help to meet this condition.
6. Post designs are based on partial fixity condition due to embedment in soil.
7. Footing excavations should be backfilled with parent material unless otherwise specified by a competent designer.

Table 1.3.2.I. Post Sizes for Farm Buildings of Low Human Occupancy (With Second Storey Loading)

Forming Part of Sentence 1.3.2.(1)

Legend - Post Sizes: A = 89 mm x 140 mm · B = 140 mm x 140 mm · C = 140 mm x 184 mm

Notes to Table 1.3.2.I.:

1. Designs are based on load combinations of total roof load, wind load and stored product acting at the same time on a closed building.
2. All notes following Table 1.3.2.A. apply, with the following conditions/exceptions:

• 14.6 kN/m loading: Full 4.8 m sidewall hay/straw storage space above. It is supported by beams spaced at 3.6 m o.c. The outside plate carries a 1.8 m floor width. If the loading is greater, refer to a qualified person for design.
• 7.3 kN/m loading: Full 2.4 m sidewall hay/straw storage space above or a gambrel roof structure > 9.14 m in total width. Floor support beams as above.
• 3.6 kN/m loading: Small gambrel roof structure or storage space for light storage. Floor support beams as above.

Table 1.3.2.J. Round Posts

Notes to Table 1.3.2.J.:

1. When selecting round, ungraded lumber, ensure that the material is of good quality.
2. Any timber that is in contact with ground shall be chemically treated to resist growth of fungus and decay.
3. Equivalent diameter indicated in this Table refers to the smallest diameter of a tapering pole.
4. Used hydro or telephone poles may be used if they are of good quality and are chemically treated to prevent decay.
5. Indicated equivalent diameter will provide bending, shear and deflection resisting capabilities equal to or better than the rectangular section that it replaces.

Table 1.3.3.K. Common Rafter Sizes for Farm Buildings of Low Human Occupancy

Forming Part of Sentence 1.3.3.(1)

Legend - Rafter Sizes: A = 38 mm x 89 mm · B = 38 mm x 140 mm · C = 38 mm x 184 mm · D = 38 mm x 235 mm · E = 38 mm x 286 mm

Notes to Table 1.3.3.K.:

1. The rafter span is the unsupported length of the rafter from plate to plate or from plate to ridge. A dead load of 0.24 kPa is incorporated to allow for weight of the roof sheathing and rafter.

Table 1.3.3.L. Common Rafter Sizes for Farm Buildings of Low Human Occupancy

Forming Part of Sentence 1.3.3.(1)

Legend - Rafter Sizes: A = 50.8 mm x 101.6 mm · B = 50.8 mm x 152.4 mm · C = 50.8 mm x 203.2 mm · D = 50.8 mm x 254.0 mm · E = 50.8 mm x 304.8 mm · F = 76.2 mm x 304.8 mm · G = 76.2 mm x 355.6 mm · H = 101.6 mm x 304.8 mm · I = 101.6 mm x 355.6 mm

Notes to Table 1.3.3.L.:

1. The rafter span is the unsupported length of the rafter from plate to plate or from plate to ridge. A dead load of 0.24 kPa is incorporated to allow for weight of the roof sheathing and rafter.

Table 1.3.3.M. Floor Joists for Farm Buildings of Low Human Occupancy - Intermittent Loads

Forming Part of Sentence 1.3.3.(1)

Legend - Joist Sizes: A = 38 mm x 89 mm · B = 38 mm x 140 mm · C = 38 mm x 184 mm · D = 38 mm x 235 mm · E = 38 mm x 286 mm

Notes to Table 1.3.3.M.:

1. Loads are applied to the floor intermittently. (When loads are applied for extended periods of time, use Table 1.3.3.N. ).
2. A dead load of 0.48 kPa is incorporated to allow for the dead weight of the floor system.

Table 1.3.3.N. Floor Joists for Farm Buildings of Low Human Occupancy - Continuous Loads

Forming Part of Sentence 1.3.3.(1)

Legend - Joist Sizes: A = 38 mm x 89 mm · B = 38 mm x 140 mm · C = 38 mm x 184 mm · D = 38 mm x 235 mm · E = 38 mm x 286 mm

Notes to Table 1.3.3.N.:

1. For use of floors that support hay, straw, grain or other continuous loads.
2. A dead load of 0.48 kPa is incorporated to allow for the dead weight of the floor system.

Table 1.3.3.O. Built-up Wood Beam Sizes for Farm Buildings of Low Human Occupancy - Intermittent Loads

Forming Part of Sentence 1.3.3.(1)

Legend - Beam Sizes: A = 3 - 38 mm x 184 mm · B = 4 - 38 mm x 184 mm · C = 3 - 38 mm x 235 mm · D = 5 - 38 mm x 184 mm · E = 3 - 38 mm x 286 mm · F = 4 - 38 mm x 235 mm · G = 6 - 38 mm x 184 mm · H = 5 - 38 mm x 235 mm · I = 4 - 38 mm x 286 mm · J = 6 - 38 mm x 235 mm · K = 5 - 38 mm x 286 mm · L = 6 - 38 mm x 286 mm

Notes to Table 1.3.3.O.:

1. Loads are applied to the beam intermittently.
2. A dead load of 0.584 kN/m is assumed for all beams.
3. Floors systems supporting heavy loads over larger spans will require the use of steel beams or other specialized materials.

Table 1.3.3.P. Built-up Wood Beam Sizes for Farm Buildings of Low Human Occupancy - Continuous Loads

Forming Part of Sentence 1.3.3.(1)

Legend - Beam Sizes: A = 3 - 38 mm x 184 mm · B = 4 - 38 mm x 184 mm · C = 3 - 38 mm x 235 mm · D = 5 - 38 mm x 184 mm · E = 3 - 38 mm x 286 mm · F = 4 - 38 mm x 235 mm · G = 6 - 38 mm x 184 mm · H = 5 - 38 mm x 235 mm · I = 4 - 38 mm x 286 mm · J = 6 - 38 mm x 235 mm · K = 5 - 38 mm x 286 mm · L = 6 - 38 mm x 286 mm

Notes to Table 1.3.3.P.:

1. For use of floors that support hay, straw, grain or other continuous loads.
2. A dead load of 0.48 kPa is assumed for all beams.
3. Floor systems supporting heavy loads over larger spans will require use of steel beams or other specialized materials.

Table 1.3.3.Q. Ungraded Lumber, Full-Dimension Roof Beam Sizes for Farm Buildings of Low Human Occupancy

Legend - Built-up Wood Beam Sizes: A = 3 - 50.8 mm x 203.2 mm · B = 4 - 50.8 mm x 203.2 mm · C = 3 - 50.8 mm x 254.0 mm · D = 5 - 50.8 mm x 203.2 mm · E = 6 - 50.8 mm x 203.2 mm · F = 4 - 50.8 mm x 254.0 mm · G = 5 - 50.8 mm x 254.0 mm · H = 4 - 50.8 mm x 304.8 mm · I = 5 - 50.8 mm x 304.8 mm · J = 6 - 50.8 mm x 304.8 mm

Notes to Table 1.3.3.Q.:

1. Ungraded lumber, full-dimension, built-up wood beam.
2. A dead load of 0.584 kN/m is assumed.
3. Beams are sized for roof load only.

Table 1.3.3.R. Ungraded Lumber, Full-Dimension Roof Beam Sizes for Farm Buildings of Low Human Occupancy

Legend - Sawn Beam Sizes: A = 127.0 mm x 203.2 mm · B = 127.0 mm x 254.0 mm · C = 152.4 mm x 254.0 mm · D = 203.2 mm x 254.0 mm · E = 203.2 mm x 304.8 mm · F = 254.0 mm x 304.8 mm · G = 254.0 mm x 355.6 mm

Notes to Table 1.3.3.R.:

1. Ungraded lumber, full-dimension, sawn wood beam.
2. A dead load of 0.584 kN/m is assumed.
3. Beams are sized for roof load only.

Table 1.3.3.S. Roof Plate-Beams and Lintels for Farm Buildings of Low Human Occupancy

Legend - Roof Plate-Beam and Lintel Sizes: A = 2 - 38 mm x 184 mm · B = 3 - 38 mm x 184 mm · C = 4 - 38 mm x 184 mm · D = 2 - 38 mm x 235 mm · E = 3 - 38 mm x 235 mm · F = 4 - 38 mm x 235 mm · G = 2 - 38 mm x 286 mm · H = 3 - 38 mm x 286 mm · I = 4 - 38 mm x 286 mm

Notes to Table 1.3.3.S.:

1. Trusses are at 1.2 m on centres.
2. Plate-beam/lintel loading can be very significant.
3. Specifications for anchorage at supporting posts must be specified by a competent designer.

Table 1.3.3.T. Roof Plate-Beams and Lintels for Farm Buildings of Low Human Occupancy

Legend - Roof Plate-Beam and Lintel Sizes: A = 2 - 50.8 mm x 203.2 mm · B = 3 - 50.8 mm x 203.2 mm · C = 4 - 50.8 mm x 203.2 mm · D = 2 - 50.8 mm x 254.0 mm · E = 3 - 50.8 mm x 254.0 mm · F = 4 - 50.8 mm x 254.0 mm · G = 2 - 50.8 mm x 304.8 mm · H = 3 - 50.8 mm x 304.8 mm · I = 4 - 50.8 mm x 304.8 mm

Notes to Table 1.3.3.T.:

1. Trusses are at 1.2 m on centres.
2. Plate-beam/lintel loading can be very significant.
3. Specifications for anchorage at supporting posts must be specified by a competent designer.

Table 1.3.4.U. Stud Sizes for Farm Buildings of Low Human Occupancy (Single Storey)

Forming Part of Sentence 1.3.4.(1)