Farm Building Standards: Canada: 1965. Supplement No. 6 to the National Building Code of Canada

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• FARM BUILDING STANDARDS

•

• CANADA

1965

SUPPLEMENT No.6 TO THE

NATIONAL BUILDING CODe

OF CANADA

Issued by the

ASSOCIATE COMMITTEE ON THE NATIONAL BUILDING (ODE

NATIONAL RESEARCH COUNCIL

OTTAWA, CANADA

NRC No. 7909 Price; 50 cents

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ASSOCIATE COMMITTEE ON

T

HE

NATIONAL BUILDING CODE

1964-1965

R. F. J..eggct (Chairman) E. A. Alleut D. C. Beam S.D.C. Chutter A. F. Duffus J. J. Dussault W. R. Edmonds H. Elder J. H. Jenkins J. S. Johannson S. D. Lash H. A. Lawless G. C. Lount J. P. Lupien D. A. !\'latheson H. H. G. Moody G. S. Mooney* A. T. l\Iuir B. Pelletier L.-P. Pieard S. A. Sasso R. A. W. Switzer A. Tubby

C. G. E. Downing (ex officio)

D. T. Wright (ex officio)

J. M. Robertson (Secret.ary)

FARM BUILDING

STANDARDS COMMITTEE

1965

C. G. E. Downing (Chairman) G. L. Calver J. A. Choiniere E. L. Fowler H. L. Isabelle W. Kalbfleisch D. E. Kennedy J. Le.ach G. R. K. Lye ;.T. McClenaghan J. E. l\ofoles C. L. Montgrain** E. B. l\loysey J. A. Rooots L. M. Staley F. H. Theakston J. E. Turnbull J. K. \\T. Slater (corresponding men her)

D. A. Lutes (Secretary)

Contributions made to the revision to this i sue made by:

E. Brubaker A. Kingdon. P. Koens

*Deceased July 1965 *"R~ igned De<>emi>€'r 1965

•

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FARM BUILDING STANDARDS

CANADA

1965

SUPPLEMENT No.6 TO THE

NATIONAL BUILDING CODE

OF CANADA

Issued by the

ASSOCIATE COMMITTEE ON THE NATIONAL BUILDING CODE

NATIONAL RESEARCH COUNCIL

OTTAWA, CANADA

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This document is under continuous review and will be amended annually if necessary. Comments on the current edition will be

received until July 1, 1967 by the Secretary of the Associate Committee on the National Building Code, National Research Council, Ottawa.

Ce document, ainsi que toutes les autres sections du Code national

du batiment, sera disponible en fran~ais d'ici quelque temps Toutes

demandes doivent etre adressees au Secreteire, Comite associe sur Ie Code

natio~al du batiment, Counseil national de recherches, Ottawa, Canada.

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FOREWORD

Farm Building Standards, 1966 has been developed as a guide for those interested in the design, construction, remodelling and evaluation of a wide variety of farm buildings, excluding the farm dwelling.

It provides general recommendations and detailed specifications to

serve as references, with the intent of obtaining safe and efficient

performance and economy within such buildings. It is recognized that

there are variations of good practice which may be equally satisfactory as those included and should be pennitted if properly evaluated by a recognized testing agency or through experience with good engineering practice.

Individual designers may go beyond any of the recommendations

included in the development of functional and efficient buildings, as

required for the multi-purpose requirements of many types of farm

buildings. I

1.

2.

The Supplement covers three main

parts:-Basic standards, which deals primarily with specifications related to design and construction of new farm buildings, and to the alteration of existing farm buildings.

The specifications refer primarily to structural sufficiency, fire pre-vention, safety, health and sanitation, and are recommended

min-imums necessary not only for the protection of people, but also to

minimize loss of livestock and stored produce.

Good practice and performance, which relates primarily to the func-tional requirements of farm buildings and to good construction practices.

The recommendations and specifications are optimum, consistent with good management practices to permit efficient production and storage and economical construction.

3. Appendices, which include technical data and information as

refer-ence material for the various sections of the Supplement.

This document is published as a Supplement to the National Building

Code of Canada, 1965, and is not intended to be mandatory.

The work of preparing the Standards has been carried out through a Committee, consisting of engineers and specialists from universities, government, related industries and .services.

It is intended that Farm Building Standards represents contemporary

building practices in Canada.

C. G. E. Downing, Chairman,

Farm Building Standards Committee of Associate Committee on the National Building Code.

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Acknowledgments

Permission to use material from the following documents has

been kindly granted to the Associate Committee and is gratefully

acknowledged

-Agricultural Engineering Year Book 1963 (American Society of

Agricultural Engineers).

Agriculture Engineers Digest 1963 (Midwest Plans Service, Ames,

Iowa.)

Farm Water Supplies (Ontario Dept. of Agriculture, Bulletin 476). Grain Storage Loads, "Farm Construction Standards Committee

Paper" (American Society of Agricultural Engineers).

Heating, Ventilating and Air Conditioning Guide 1951, (American

Society of Heating and Ventilating Engineers.)

Journal, September 1959, September 1960 and December 1962

(American Society of Agricultural Engineers),

Proceedings of Michigan Silo C01i-!erence 1961, J. S. Boyd. Michigan

State University),

Transactions, 1969 (American Society of Agricultural Engineers),

Other References

The Associate Committee wishes to acknowledge gratefully the

assistance that has been obtained by the Farm Building Standards

Com-mittee from the following publications; if any information has thus been

used for which prior formal permission should have been obtained, this has only been done unwittingly in the common task of assisting with the improvement of farm buildings, and regret is here recorded for any such omission.

An Act Respecting Food and Drugs, "Revised Statutes of

Newfound-land 1952", Chapter 56 (Dept. of Public Health, Province of New-foundland.

Commercial Storage of Fruits, Vegetables, Florists and Nursery Stock,

"Agricultural Handbook 66" (U.S. Department of Agriculture).

Farm Service Buildings, H. E. Gray (McGraw-Hill).

Farm Structures, H. J. Barre and L. L. Sammet (John Wiley and

Sons).

Henderson Report to National Institute of Health (U.S. Public Health

Service).

Manitoba Dairy Act, "Chapter 58, Statutes of Manitoba 1954" and

"Manitoba Regulation 1558" (Dept. of Public Health and Welfare, Province of Manitoba).

Minimum Requirements for Construction of Equipment and Mainten-ance of Milk Plants and Receiving Stations (Dept. of Health and

Public Welfare, Province of Manitoba).

PMBC Forms, (Plywood Manufacturers Association of British

Col-umbia, 1477 West Pender Street, Vancouver 5, B.C.)

Regulations Governing the Construction, Maintenance and Operation of Class D Stock Yards "Livestock Disease Act, Alberta Regulation

57-59" (Dept. of Public Health, Province of Alberta).

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Regulations for Milk Production, Milk Pasteurization Plants and Milk Plants ,Dept. of Health, Province of Nova Scotia).

Regulations Governing Milk and Certain Milk Products, 1959 (Dept.

of Public Health, Province of Saskatchewan).

Regulations Governing the Production, Manulactu1'e, Grading and Composition 01 Dairy Products unde1' the DaiTyman's Act "Chapter

74, RSA 1955, Alberta Regulation 567-57" (Dept. of Public Health, Province of Alberta).

Regulations re Grading and Inspecting 01 Honey unde1' the Vegetable

and Honey Sales Act 1947 (Dept. of Public Health, Prov·ince of Saskatchewan) .

Regulations under the Milk Industry Act "B.C. Regulation 32-58 and

102-58, October 23, 1958" (Dept. of Public Health, Province of

Saskatchewan) .

Regulations under the Milk Industry Act (Dept. of Public Health,

Province of Ontario).

Short Term Storage of Horticultural Crops, J. L. Truscott, (Horti-cultural Products Laboratory, Vineland Station, Ont.)

The Public Health Act Standard Milk Regulations, 1960 (Dept. of Public Health, Prince Edward Island).

Papers prepared by the Canadian Institute of Timber Construction. Papers prepared by the Portland Cement Association.

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•

1.1 1.1.1. 1.1.2. 1.1.3. 1.1.4. 1.1.5. 1.1.6. 1.1.7. 1.1.8. 1.1.9. 1.2. 1.2.1. 1.2.2. 1.2.3. 1.2.4. 1.2.5. 1.2.6. 1.3. 1.3.l. 1.3.2. 1.3.3. 2.1. 2.1.1 . 2.1.2. 2.1.3. 2.1.4. 2.1.5. 2.2. 2.2.1. 2.2.2. 2.2.3. 2.2.4. 2.2.5. 2.2.6. 2.3. 2.3.1. 2.3.2. 2.3.3. 2.3.4. 2.3.5. 2.3.6.

m

APPENDICES A Loads imposed by Stored Grain and Silage .. ... 75

B Concrete and Mortar Mixes ... 83

C Fire Performance Ratings ... . . . .. 87

D Water Supply ... ... 91

E Waste Disposal . ... 99

F Unit Weights of Materials ... 107

G Vehicle and Equipment Storage ... ... 113

H Winter Design Temperatures (5% Basis) ... 117

I Heat and Moisture Production of Livestock ... 119

J Heat of Respiration of Stored Products ... 129

K Ventilation ... ... 135

L Electrical Services ... ... ... 141

M Cladding . . . .. ... 149

N Insulation Values of Building Materials ... 159 (vii)

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Table

LIST OF TABLES

I. Floor Loads Due to Use ...

Page

2

5 II. Design Bearing Pressures of Soils ond Rocks ... .

lIE. Species Groups .... ... ... . ... . 9

IV. Allowable Unit Stresses (a) In Bonding ... 10

(b) In Compression Parallel ... 11

(c) In Longitudinal Shear ... . 13

V. Recommended Minimum Distances Between Buildings to Prevent the Spread of Fire due to Radiation ... 19

VI. Dimensions for Stanchion Tie-Stalls for Dairy Cows... 30

VII. Litter Alley Width . . . .. ... 31

VIU. Bedding Requirements for Dairy Cattle ... 32

IX. Requirements for the Accommodation of Beef Cattle .. 33

X. Requirements for the Accommodation of Sheep ... 34

XI. Requirements for the Accommodation of Swine ... XII. Requirements for the Accommodation of Horses XIU. Requirements for Floor Housing of Laying Hens 35 .. 36

37 XIV. Requirements for the Accommodation of Broilers, Roasters, and Replacement Pullets ... . . .. ... 38

XV. Feed Requirements for Raising Broilers, Roasters and Replacement Pullets 39 XVI. Feed Consumption of Laying Hens ... 39

XVII. Requirements for the Accommodation of Turkey Breeding Flocks . . . 39

XVIII. Greenhouse Area Requirements per Acre of Transplanted Crop ... '. . ... .. 41

XIX. Dimensions of Tobacco Kilns 42 XX. Recommended Temperature and Humidity Limits for Closed Animal Production Buildings . . . .. 44

XXI. Temperatures and Humidities for Product Storage XXII. Daily Water Requirements of Livestock

45

56 XXIII. (a) Sediment-Septic Tank Capacities (b) Disposal Field XXIV. Loading Rates Per Acre of Lagoon XXV. Surface Area for Anaerobic Operation . 58 ... 59

59 .. ... 60

XXVI. (a) Anaerobic Lagoons for Combined Anaerobic-Aerobic System Designed for a Retention Period of One Year 61 (b) Aerobic Lagoons for Combined Anaerobic-Aerobic System . .. ., .. ,. 61 (viii)

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Table XXVll.

xxvm.

XXIX. XXX. A-I. B-1. B-ll. B-lll. C-l C-2 C-3 D-I. D-ll. F-I.

t

F-ll. G-I. I-I. J-I. L-I. L-II. L-Ill. L-IV. L-V. L-VI. M-I. M-ll. M-III. N-I. Page

Maximum Exposure to Wood Shingles . . . .. 65

Grades and Uses of Plywood .... .. ... 66

Wall Sheathing, Cladding and Interior Finish ... 68

Roof Sheathing ... , . . . ... " ... 70

Coefficients of Friction (u') for Grains at Various Moisture Contents on Various Surfaces ... . Recommended Mortar Mixes ... . Guide for Ordering Ready-Mixed Concrete .... 79 84 85 Recommended Concrete Mixes for On-the-Job Mixing. . .. 86

Estimated Fire Periormance Ratings for Frame Exterior WaIls ... ... 88

Estimated Fire Performance Ratings for Masonry WaIls 88 Estimated Fire Performance Ratings for Floors... 89

Water Heater Requirements ... . . . .. ... 92

Nominal Sizes of Steel Distribution Pipes ... 92

Unit Weights of Construction Materials and Units ... 108

Apparent Densities of Agricultural Materials ... 110

Areas and Dimensions of Farm Vehicles and Equipment.. 114

Guide to Air Flow Requirements in Closed Livestock Buildings .... .... .. 120

Heat of Respiration of Stored Products ... 130

Copper Conductors, 230-240 Volts, Single Phase, 2 Percent Voltage Drop . . . .. 142

Aluminum Conductors, 230-240 Volts, Single Phase, 2 Percent Voltage Drop . . . .. 143

Copper Conductors, 115-120 Volts, Single Phase, 2 Percent Voltage Drop " . . . . . . .. 144

Copper Conductors, Single-Phase Motors, 115-230 Volt, 2 Percent Voltage Drop . . . 145

Copper Conductors, Three-Phase Motors, 208 Volts, 2 Percent Voltage Drop 146 Minimum Size of Grounding Conductor 147 Loading Table for Exterior Cladding, Profile No.1 ... 150

Loading Table for Exterior Cladding, Profile No.2. . . . .. 151

Loading Table for Exterior Cladding, Profile No.3 ... 152

Insulation Value of Building Materials . . . .. 160

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II

ILL USTRATIONS

Figure Page

1A Lateral Pressures for Corn Silage ... 81

1D Drilled-Well Construction ... 93

2D Dug-Well Construction ... ... 94

3D Spring Protection ... 94

4D Shallow-Well Pump Installation ... 95

5D Deep-Well Reciprocating Pump Installation ... 95

6D Deep-Well Centrifugal-Jet Pump Installation ... 96

7D IE 2E 3E 4E 5E 6E 7E Deep-Well Submersible Pump Installation ... . Concrete Block Disposal Pit Cross Section of Incinerators Free-Loading Inlet ... . Centre-Loading Inlet ... . .... . Direct Loading from Feedlot ... . ... . Control Structures Alternate Outlet

97

100 101 102 102 102 103 104 BE Septic Tank ... 104 9E Disposal Field ... 105

IH January Design Temperature Map (5% Basis) ... 118

11 Milk Production V s. Temperature ... 121

2I Evaporative Heat Losses of Cattle ... ... 121

31 Total Heat and Moisture Dissipation Rates with Dairy Cattle in Tie Stalls ... ... .. 122

41 Total Heat Elimination of Chickens at Various Temperatures under Basal Conditions ... 122

51 Grains of Moisture Respired per Hour for Different Ages of Chickens and Temperatures ... 123

61 Total Heat Produced by Caged Layers per pound of Body Weight in Relation to Ambient Temperature ... 123

71 Total Heat per pound of Weight and Percent of Sensible and Latent Heat Produced by Caged Layers in Relation to Ambient Temperatures '" ... 124

81 Total Moisture Removed by Ventilation System of Test Room Housing Swine . . .. ... . . . . .. ... 124

91 Influence of Ambient Temperature and Animal Weight on Total Heat Lost by Swine ... ... ... . 125

101 Effect of Sheep Weight upon Heat Production at Air Temperature of 70° to 72° F. ... 125

111 Effect of Air Temperature upon Heat Production of Sheep. 126

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Figure Page

121 Building Sensible and Latent Heat, and Animal Weight for

Sows and Litters . ... 127

1K Resistance of Grains and Seeds to Air Flow ... ... 136

2K Resistance of Shelled Corn and Wheat to Low Air Flows.... 137

3K Friction of Air in Straight Ducts, 1,000 to 100,000 cu. ft. of air per minute ... 138

4K Friction of Air in Straight Ducts, 10 to 2,0000 cu. ft. of air per minute .. . . . . . . 139

5K Rectangular Duct Conversion Chart.. . .... ... . . . ... 140

6K Loss in 9O-Deg. Elbows of Rectangular Cross-Section... 140

7K Loss in 90-Deg. Elbows of Round Cross-Section ... , 140

1M Profile No.1 ... " ... 150 2M 3M Profile No. 2 Profile No.3 151 152 4M Accessories for Aluminum and Steel Cladding ... 153

5M Load/Span Graph for % in. Sheathing Grade Douglas Fir Plywood ... . . . . . . .. 154

6M Load/Span Graph for 1h in. Sheathing Grade Douglas Fir Plywood ... ... .... .. 155

7M Load/Span Graph for 3;4 in. Sheathing Grade Douglas Fir Plywood ... ,... 156

8M Load/Span Graph for 3;4 in. (5 ply) Sheathing Grade Douglas Fir Plywood ... , ... 157

9M Load/Span Graph for 3;4 in. (7 ply) Sheathing Grade Douglas Fir Plywood ... ,... ... ... 158 (xi)

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PART 1 BASIC STANDARDS

SECTION 1.1 DESIGN

SUBSECTION 1.1.1. GENERAL

The requirements of Section 1.1. apply to the design and construction

of new farm buildings and to the alterations of existing farm buildings. 1.1.1.1. Reference to Good Practice

In this Part where the term "good practice" is used or where such words as "adequate", "sufficient", "suitable", "reasonable" or "effective" or derivatives thereof are used, it is intended to ensure sound, safe con-struction on the farm.

1.1.1.2. Design

Farm buildings should be designed in accordance with Part 4, of the "National Building Code of Canada" unless stated otherwise. 1.1.1.2.(1) Conditions-The structural members of a farm building should be designed to have sufficient capacity to resist safely and effectively the following

(a) All climatic loads that may probably be applied to them during the expected life of the building (in accordance with Supple-ment No. 1 to the National Building Code of Canada). (b) All loads due to the intended use of the building that may

probably be applied to them during the period of that use. (c) All loads that may reasonably be expected to be applied to

them during construction of the building. (d) All loads due to the materials of construction.

(e) All lateral loads due to earth and water pressure that may

reasonably be expected to be applied on any part of the building below ground level.

1.1.1.3. Materials and Building Components

Materials and building components not specifically described in this Part may be used provided their suitability has been establishea

(1) by test published by a recognized testing laboratory which simulates anticipated service conditions, or

(2) according to recognized engineering principles. 1.1.1.4. Construction Methods

Construction methods should conform to good practice. 1.1.1.5. Drawings and Specifications

Drawings should indicate

(1) the dimensions, location and size of all structural members and connections in sufficient detail to enable the design to be checked,

(2) sufficient detail to enable the loads due to materials of con-struction incorporated in the building to be determined, and

(3) all loads, other than those due to materials of construction

incorpora~ed in the building, used in the design of the structural members and connections.

1.1.1.6. Construction Safety Measures

Construction safety measures should conform to Part 8, "National Building Code of Canada", where applicable.

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SUBSECTION 1.1.2. STRUCTURAL LOADS AND PROCEDURES

1.1.2.1. Loads

1.1.2.1.(1) Loads Due to Materials of Construction - The minimum

design load, due to materials of construction incorporated in a farm building tributary to a structural member is

(a) the weight of the member itself,

(b). the weight of all materials of construction incorporated in the building to be supported permanently by the member, including permanent service equipment. and

(c) the estimated weight of possible future additions.

(2) Loads Due to Use-The minimum design load on any area of floor. due to the use of the area is listed in Table I.

TABLE I Floor Loads Due to Use

Use of Area of Floor Design Live Load

Cattle

tie stall barns

loose housing (holding area) slotted floors milking parlours milkrooms or milkhouses Sheep Swine solid floors slotted floors Horses Chickens floor housing cages Turkeys Product Storage 14achinery Storage Greenhouses Maintenance Shops

~ See 1.1.2.1. (2)(a) "Loads for Livestock on Slotted Floors".

psf . 70 80

•

70

SO··

30 40

•••

100

40····

40 •••••

••••••

50 70

** FlIoor construction under bulk tanks shoulil be designed according to the weight of the tank plus contents.

0** See 1.1.2.1.(2)(a) "Loads for Livestock on Slotted Floors".

un Where a space is provided for the aecumulation of manure, the design load should be based on 66 psf. per foot of depth.

o~u~ The design load for product storage should be calculated on the basis of the individual weights (See Appendix F) but in no ease less than 100 psf.

'*0";'00 See 1.1.2.1(2) (b) "Loads for M.acilinery Storage".

(2) (a) Loads for Livestock on Slotted Floors

(i) Slat loads for cattle on slotted floors should be calculated as follows:

(1) Assume individual hoof loads for 1/4 the animal weight. (2) Assume distance between an animal's hooves as 1 ft. and

centre to centre distance between adjacent animals as 2 ft. (3) Place on the chosen space the maximum number of hoof

loads possible. 2

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1.1.2.1.(2) (a)

(4) Arrange the loads to give maximum moment or shear. Maximum shear occurs when two superimposed hoof loads occur at the support.

(ii) Slat loads for swine on slotted floors should be caluclated as for beef in Clause 1.12.1(2) (a) (i) except for hoof distance and centre to centre distance between animals should be taken as 6 in.

and 1 ft., respectively.

(iii) Loads for beams supporting slats in a slotted floor system for all animals should be taken as 100

Ibs.

per sq. ft.

(b) Loads for Machinery Storage.

(i) Machinery storage (uniformly distributed): The minimum design load on an area of floor, used for farm machinery storage with traffic limited to access and egress should be 150 psf. except where it is anticipated that the area will be occupied by either loaded farm trucks or large farm tractors (large tractors are those having a weight in excess of 13,000 pounds where weight restriction includes effect of mounted equipment) then the design load should be 200 psf.

(ii) Machinery storage (concentrated): The minimum design loads due to probable concentrations of loads resulting from use of an area of floor is as follows

(1) For tractors and implements:-5,OOO lb. per wheel at a concentration of 3,600 psf.

(2) For loaded trucks not exceeding 20,000 lb. G.V.W.*:- 8,000 lb. per wheel at a concentration of 13,000 psf.

(3) For loaded trucks exceeding 20,000 lb. G.V.W.*: - 12,000 lb. per wheel at a concentration of 13,000 psf.

(iii) Machinery storage (loading and processing): In cases where the machinery storage area (minimal traffic or driveway) is to serve as a place for loading, unloading or processing, minimum

design loads for such areas should be multiplied by a factor of 1.5 due to the weight and impact or vibrations of the piece of machinery or equipment.

(c) Loads Imposed by Com and Grass.

(i) Lateral pressure: Cylindrical concrete or wood silos for com or grass silage not exceeding 70 per cent moisture (wet basis) should be designed for lateral pressure as determined by the formula to follow. This formula is not intended for design of grain storage cylinders, but silos designed by this formula are reasonably safe for normal shelled corn pressures.

L

=

100

+

1:92 h do.55

in which L

=

lateral presure, psf.

h vertical distance from top of silo wall, ft. d silo diameter, ft.

(H) For design of circumferential reinforcement in concrete silos, the allowable unit stresses should not be increased as permitted in "low human occupancy" buildings, under 1.1.2.2.(b).

(iii) Vertical wall loads: Cylindrical concrete silo walls for com or grass silage should be designed to vertically support dead wall weight of silage above the sloping surface of a circular cone whose base is the floor of the silo and whose height is 3.21 times the silo diameter.

(d) Loads Imposed by Stored Grain

For information relating to loads imposed by stored grain (shal-low bins, deep bins, hopper bottoms, exposed horizontal girts,

thermal effects. moisture effects. unloading effects (see Appendix A. Physical properties of stored crops are given in Table A-I).

*G.V.W.=Gross Vehic1e Weight

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1.1.2.1.

(3) Loads due to snow - Loads due to snow should be in accordance

with Articles 4.1.3.7. to 4.1.3.10 inclusive of Section 4.1. "Structural Loads and Procedures" of the "National Building Code of Canada".

(4) Loads due to wind - Loads due to wind should be in accordance

with Articles 4.1.3.11 and 4.1.3.13 of Section 4.1. "Structural Loads and Procedures" of the "National Building Code of Canada".

(5) Loads due to rain - Loads due to rain should be in accordance

with Article 4.1.3.14 of Section 4.1. "Loads and Procedures" of the "National Building Code of Canada".

1.1.2.2. Design procedures.

1.1.2.2 .. (1) Connections should be designed as provided for in the National Building Code to carry any combination of live and dead loads provided for in the design. Where design procedures are not covered in the National Building Code, standard engineering design procedures should be used.

(2) Allowable Stresses. The following Clauses are designed to per-mit farm building design with a reduced overall safety factor in recog-nition of low risk of human life and low value of contents or low risk to loss of contents.

(a) For purposes of structural design, "low human occupancy" farm buildings include any buildings other than those intended for high human occupancy. Buildings such as those containing processing rooms, workshops, auction or show arenas, or other areas likely to be occupied by several persons over extended periods should be considered to have "high human occupancy".

(b) For the structural design of "low human occupancy" farm buildings, the allowable stresses tension, compression, bending,

and shear as set forth in Tables IV, (a),(b) and (c) or the

National Building Code may be increased by 25 per cent as pro-vided for in 1.1.2.1.(2)(c)(ii).

(c) Increases in allowable stresses for "low human occupancy" farm buildings in accordance with Clause 1.1.2.2.(2)(b) may be applied cumulatively with other modification factors for application con-ditions provided for in the National Building Code.

(3)

Deflections-(a) Except where plaster, ceramics or other brittle materials form part of the assembly subject to deflection, the deflection of trusses, beams, floor and roof systems, and similar structural components for farm structures generally need not conform to any specific limitations.

(b) Deflections should be taken into account in the design, based on live load and dead load, to ascertain that deflection under design load will cause interference with the operation of doors, windows or equipment.

(c) Where plaster, ceramics or other brittle materials form part of the assembly subject to deflections, the deflection should be limited to 1/360 of the span, based on live load only.

SUBSECTION 1.1.3. FOUNDATIONS 1.1.3.1. General

1.1.3.1.(1) Farm buildings should be adequately supported by foundations. (2) Foundations should be interpreted to include footings and piling, walls, posts, piers, pilasters, rafts, slabs, grade beams, grillages or design forms which extend below grade for the purpose of supporting the farm building on the ground.

(3) Foundations should be designed

(a) for the existing soil according to recognized engineering principles, or 4

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1.1.3.1. (3)

(b) on the basis of past experience with the soil conditions where

the foundation is to be built.

(4) Vertical loads should be provided for in the design. through the

distribution of the load to the soil by compression or skin friction.

Design for skin friction should be in accordance with Article 4.2.2.18 of the "National Building Code of Canada."

1.1.3.2. Footings 1.1.3.2.(1)

General-(a) Except as permitted in Sentence (d) below, footings should be

provided under foundations walls, columns, piers, and poles to

distribute the loads in accordance with the allowable bearing

values of the supporting material in Table II.

(b) The bearing surface on gravel, sand or silt shall not be less

than 1 ft. below grade; however, where this surface is more than

1 ft. below grade and is embedded on aU sides by the same soil,

the maximum design bearing pressure of the soil is that listed

in Table II increased at the rate of 20 per cent for each foot

increase in depth but not more than 200 per cent.

(c) Where a f.oundation bears on gravel, sand or silt, and where the highest level of the ground water is, or is likely to be, higher than an elevation defined by the bearing surface less the width of the footing, the maximum bearing pressure shall be 50 per cent of that determined in Sentences (a) and (b) above.

TABLE II

Design Bearing Pressures of Soils and Rocks

Type and Condition of

Soil or Rock Cohesionless

Soils-dense sand, Soils-dense sand-and-gravel ·Cohesive

Soils-dense silt

medium dense silt hard clay stiff clay firm clay soft clay

Miscellaneous Soils and Rock-till, dense

cemented sand-and-gravel

clay-shale-especial investigation required since insufficient load may cause problems)

Rock-massive foliated sedimentary soft or sheltered

• A cohesive soH described as

Design Bearing Pressure, psf 6,000 3,000 2,000 6,000 4,000 2,000 1,000 10,000 20,000 100,000 80,000 40,000 20,000

hard is a soil impossible to indent with the thumb but readily indented with the

thumbnail

stiff is a soil difficult to indent with the thumb; with difficulty it can be remoulded by hand

firm is a soil that can be indented by moderate thumb pressure, and

80ft is a ,soil that can be penetrated severa.l inches with the thumb.

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=

1.1.3.2.(1)

(d) Footings may be omitted if the safe bearing capacity of the soil or rock is not exceeded.

( e) Footings should be proportioned to minimize differential settle-ment.

(f) H footings are to be supported on consolidated fill or unstable soil, they should be designed for these conditions and the build-ing so constructed that it will not be structurally damaged hy settlement.

(2). Concrete Footings for Concrete, Masonry or Stone

Walls-(a) General

(i) Wall footings should be proportioned. from the soil-bearing pressures and applied loads to minimize non-uniform settlement.

(ii) The bottom of footings should be below frost line except when on rock or on coarse grain soil, well drained to at least the depth of frost penetration.

(b) Plain Footings

(i) The minimum thiCQess of plain footings should be the minimum thickness of foundation walls prescribed in Clause 1.1.3.3.(1)(c).

(ii) The minimum width of plain footings should be the actual thickness of the supported fOWldation walls increased by the minimum thickness of foundation walls prescribed in Clause 1.1.3.3.(1)( c). .

(c) Steel Reinforced Footings

The minimum thickness of steel reinforced footings should be 9 in.

(3). Concrete Footings for Columns and Poles - Column footings should be of sufficient size to carry the concentrated loads they must support.

(a) The minimum thickness of unreinforced column footings should be 8 in.

(b) Column footings more than 3 ft. sq. should be reiBforced except where the thickness of the footing is equal to or greater than the greatest distance from the edge of the column to the edge of the footing.

(c) Precast pads for pole construction should not be used. (d) Backfill around poles should be tamped.

(4). Wood Footings for Wood or Metal Walls Columns, Posts or

Poles-(a) The minimum thickness of wood used in footings should be

Ilh

in.

(b) Wood footings should be designed so as not to exceed the allow-able unit stresses specified in Article 1.1.4.2. for the grade and species used.

(c) Wood footings should be treated in accordance with Subsection 2.3.5.

1.1.3.3. Foundation Walls

1.1.3.3.(1). Concrete and Unit Masonry Foundation

Walls-(a) Foundation walls should be designed to resist vertical and hori-zontal loads taking into account their unsupported length and height.

(b) Except as provided for in Sentence (c) the minimum thickness of foundation walls should be 8 in.

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1.1.3.3.(1).

(c) Minimum Thicknesses

(i) For buildings measuring less than 100 sq. ft. in floor area

and with superstructure walls less than 8 ft. in height, the minimum

thickness should be 6 in.

(ii) The minimum thickness of foundation walls should be 10 in. when

(1) the walls extend more than 4 ft. into unstable and poorly

drained soils,

(2) the walls extend more than 7 ft. into the ground,

(3) the total height of foundation and superstructure bearing walls

is more than 24 ft. but less than 35 ft. (see 1.1.5.2(1)(d).)

(iii) The minimum thickness of foundation walls should be 12 in. when the total height of foundation and superstructure bealing

walls is more than 35 ft.

(d) Foundation walls should extend at least 6 in. above ground.

All exterior surfaces of basement or cellar walls below grade

should be waterproofed below grade by

(i) parging the wall below finish grade with cement mortar at

least 3/8 in. thick and coving the parging over the footing if the

foundation consists of unit masonry.

(il) filling the recesses resulting from the removal of form ties with cement mortar or sealing the recesses with waterproofing

material if the foundation wall is of solid concrete, and

(iii) covering the walls with two coats of bituminous material or portland cement base paint.

(2). Wood Frame Foundation

Walls-(a) Wood frame foundation walls should be designed to resist vertical and horizontal loads taking into account their unsupported length and height.

(b) All horizontal and vertical framing, and plywood or lumber

sheathing should be treated in accordance with Subsection 2.3.5

below grade and to a minimum height of 12 in. above grade.

(3). Backfilling-Backfill should be placed carefully against the foun-dation walls to avoid damaging the walls or injuring any waterproofing, and to a level sufficiently above the finish grade so that future settlement

of the backfill will not cause the final grade to slope towards the

foundation.

1.1.3.4. Concrete Grade Beam Foundations

A concrete grade beam foundation consists of a series of concrete

piers that support a reinforced beam around the perimeter of the

building. 1.1.3.4.(1).

Piers-(a) Piers should be proportioned to carry all vertical loads and

should be reinforced to resist lateral forces and tensile stresses. The minimum cross sectional area of steel should be 0.01 times the cross sectional area of the piers.

(b) The bottom of piers should have sufficient bearing area to distribute safely the loads over the suppol'ting soil.

(c) Piers should extend below frost line to firm bearing.

(d) The minimum diameter of piers should be 10 in.

(2). Grade Beams-Grade beams should be designed to carry the live

and dead loads of the building supported by the walls and should extend at least 8 in. above grade.

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1.1.3.5. Wood Post and Plank Foundations

1.1.3.5.(1) Wood post and plank foundations should be designed to resist vertical and horizontal loads, taking into account their unsupported length and height.

(2) Both planks and posts should be treated in accordance with Subsection 2.3.5 below grade and to a minimum height of 12 in. above grade.

1.1.3.6. Concrete Slabs on Grade

1.1.3.6.(1). Slabs on Grade (with Perimeter Foundation

WaIls)-(a) A minimum of 4 in. of compacted granular material should be

provided underneath slabs.

(b) The minimum thickness of concrete slabs on grade should be 4 in.

(c) The tops of slabs should be at least 6 in. above exterior finish grade.

(d) Uniformly distributed reinforcement for slabs on grade should weigh not less than 40 lb. per 100 sq. ft.

(e) Footings for load-bearing partitions should rest on undisturbed soil The minimum thickness of such footings should be 5 in. measured from the underside of the slabs on grade and their minimum width should be 12 in.

(2). Slabs on Grade (Without Perimeter Foundation WaIls)-(a) The requirements for floating slabs should not be less than those

for slabs on grade with foundation walls.

(b) The tops of slabs should be at least 12 in. above exterior finish grade.

(c) A tapered perimeter beam should be provided with a minimum width at the base of 8 in. The beam should extend not less than 12 in. into undisturbed soil.

1.1.3.7. Wood Sills and Skirting. 1.1.3.7.(1) Wood Sills

(a) Wood sills should have a minimum thickness of 11,2 in.

(b ) Wood sills on or below grade should be treated in accordance with Subsection 2.3.5.

(2) Wood Skirting - Lumher or plywood skirting should be treated

in accordance with Subsection 2.3.5. below grade and to a minimum height of 12 in. above grade.

SUBSECTION 1.1.4. WOOD 1.1.4.1. General

Except as otherwise provided for in this Subsection, the design or appraisal of farm buildings or structural elements made from wood or wood products should be in accordance with Section 4.3, of the National Building Code of Canada.

Full inch dimensions, stated herein, are nominal and actual sizes

should be in accordance with CSA Specification 0141-1965 - "Softwood

Lumber". 8

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1.1.4.2. Allowable Unit Stresses

1.1.4.2.(1) For purposes of assigning allowable unit stresses, species are

classified according to groups given in Table III.

Group I II III IV TABLE

m

Species Groups Speeies

(a) Douglas Fir (dense) (b) Douglas Fir, Western Larch

(c) Pacific Coast Hemlock

Pacific Coast Cypress Eastern Larch (Tamarack) Jack Pine

Fir (Amabilis and Grandis) Balsam Fir

Eastern Hemlock

Pine (Lodgepole and Ponderosa) Spruce ( all species)

Western Red Cedar Pine (Red)

Pine (Western and Eastern White)

Poplar (Aspen, Large-toothed Aspen, and Balsam only)

(2) Structurally graded lumber may be assigned allowable unit stresses in accordance with Article 4.3.5.5 of the "National Building Code of Canada."

(3) All structurally graded lumber assigned allowable unit stresses should be identified by a grade mark of an inspection agency approved by the CLS Administrative Board of the Canadian Standards Association. (4) (a) Graded lumber used in low farm buildings may be assigned allowable unit stresses in accordance with Tables IV (a) IV (b) and IV (c) provided that it is identified by the appropriate grade mark of an inspection agency approved by the CLS Administrative Board of the Canadian Standards Association and provided that the framing elements are spaced at 48 in. centres or less. (b) Graded lumber used in farm buildings other than "low human

occupancy" buildings may be assigned allowable unit stresses in accordance with Tables IV (a) IV (b) and IV (c) provided that it is identified by the appropriate grade mark of an inspec-tion agency approved by the CLS Administrative Board of the Canadian Standards Association and provided that load-sharing systems are employed.

"Load-sharing systems" means a construction composed of three or more essentially parallel members spaced at 24 in. centres or less, so arranged or connected that they mutually support the load.

Reference should be made to Article 4.3.3.3 of the "National Building

Code of Canada" for further information on modification of allowable unit stresses.

(5) Allowable stress modification factors for farm buildings may be applied to values from Table IV(a), (b) and (c) in accordance with Clause 1.1.2.2.(2).

(6) Ungraded lumber should not be used in applications where the calculation of unit stresses is essential to the design.

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1.1.4.2.

TABLE JV(a)

Allowable unit stresses in bending, for the various species and Grades of Lumber in Farm Buildings. For normal duration of Load and

Dry Service Conditions.

*

Nominal Species GrolIPS and Allowable

Gradin. Rule**'* Grade Size·· Unit StreslJe8 in psi

(indaes) l(a) l(b) l(e) II III IV

British Colwnbia 2 x 4 2255 2090 1760

Lumber Manufacturers Select 2 x 6

Association Rules No. 59, Structural 2 x 8

1959 as amended 2 x 10 to Nov. 1964. 2 x 12 2 x 4 1240 1070 950 Select 2 x 6 1420 1230 1090 Merchantable 2 x 8 1500 1300 1150 2 x 10 1560 1350 1200 2 x 12 1600 1390 1230 West Coast Lumber Inspection 2 x 4 980 910 770 720 620 550 Bureau Standard 2 x 6 1925 1650 1650 1020 780 780

Grading Rules Construction 2 x 8

..

1060 1040 920

No. 15 March 15. 2 x 10 1200 1040 920 1956. Revised 2 x 12 1200 1040 920 September I, 1964 Western Wood 2 x 4 Products Association 2 x 6 1320 1320 640 470 490 (WWP A

k

Standard Standard 2 x 8 740 640 570 Grading ules. 2 x 10 800 690 610 1965. Jan. 1. 1966 2 x 12 900 780 690 Supplements. Western Wood Product Association 2 x 4 (WWPA) 2 x 6

Standard Grading Utility 2 x 8 730 620 580 500 440

Rules Jan. 1. 1965 2 x 10 860 730 680 590 520 Supplement _{2x 12} ₈₁₀ ₆₈₀ ₆₄₀ ₅₅₀ ₄₉₀ Jan. 1. 1966 2 x 4 _{1~~0 11~0}1~,65 Select 2 x 6 Structural 2 x 8 043·1953 2 x 10 C.S.A. 2 x 12 Sllecification for Structural 2 x 4 1320 _{1~?5 ?90} Timber 2 x 6 Structural 2 x 8 2 x 10 2 x 12 Eastern Spruce 2 x 4 1240 1070 950

Grading Committee Selected 2 x 6 1620 1400 1240

Rules as published Merchantable 2 x 8 1500 1300 1150

by the Maritime 2 x 10 1440 1250 1100

Lumber Bureau and 2 x 12 1600 1390 1230

the Quebec Lumber

Mfrs. Assoc. 2 x 4 720 620 550 August I. 1962 No.1 2 x 6 1200 1040 920 and (Construction) 2 x 8 1200 1040 920 Cana.dian 2 x 10 1200 1040 920 Lumbermen's 2 x 12 1380 1200 1060 Association RuJes

for White and Red Pine. 2 x 4 560 490 430

revised editi.on No.2 2 x 6 900 780 690

January 1965. (Standard) 2 x 8 1060 920 810 2 x 10 1080 940 830 2 x 12 1300 1130 1000 Cana.dian Lumbermen's 2 x 4 950 Association Rules 2 x 6 920

for White and No.1 2 x 8 920

Red Pine. revised 2 x 10 920

edition, JanuRry 2 x 12 1060 1965 10

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~l

1.1.4.2.

TABLE IV (a)* - (Cont'd)

Nominal Species Groups and Allowable Grading Rule"'*'" Grade Siae** Unit Stresses in psi

(inmes) 1(a) l(b) l(e) II III IV Canadian

Lumbermen's 2 x 4 750

Association Rules Merchantable 2 x 6 780

for White and and No.2 2 x 8 &10

Red Pine, revised 2 x 10 830

edition. January 2 x 12 1000

1965.

Eastern Pine Grading

2 x 4 650

Committee Rules for

Red and White Pine No.1 2 x 6 690

as published by the Dimension 2 x 8 740

Maritime Lumber 2 x 10 830

Bureau and Quebec 2 x 12 920

Lumber Mfrs. Assoc .• effective August I, 1962

Canadian Lumbermen's 2 x 4

Association Rules for No.2 2 x 6 410

White and Red Pine. Dimension 2 x 8 440

revised edition, 2 x 10 520

January 1965. 2 x 12 570

Committee Rules for 2 x 4

Red and White Pine No.3 2 x 6 490

as pubJished by the Dimension 2 x 8 570

Maritime Lumber 2 x 1'0 770

Bureau and Quebec 2 x 12 780

Lumber Mfrs. Assoc .• effective August I, 1962

TABLE IV (b)

Allowable Unit Stresses in compression parallel to grain for the various species and Grades of Lumber in Farm Buildings. For normal duration of

Load and Dry Service conditions, for Ratios of LID of 10 or Less.*

Nominal Species Groups and ADowable Grading Rule"''''''' Grade Size*" Unit Stresses in psi

(inches) _{l(a) l(b) l(e)} _II _III _IV 2 x 4 18.~5 1~?0 12.~0

Select 2 x 6 _{2 x 8}

British Columbia Structural 2 x 10

Lumber Manufacturers 2 x 12

Association Rules No. 59.

1959. revised 2 x 4 1160 910 910 to Nov. 1964 _Select 2 x 6 1220 960 960 Merchantable 2 x 8 _{2 x 10} 1250 _{1270 1000 1000}980 980 2 x 12 1250 1010 1010 West Coast _{2 x 4} _{1180 1180} ₉₆₀ ₇₆₀ ₇₆₀ Lumber Inspection _{2 x 6} _{1540 1320} 12.~0 1090 800 800

Bureau Standard _Construction _{2 x 8} ₁₁₅₀ ₉₀₀ ₉₀₀

Grading Rules No. 15 - 1956 revised 2 x 10 1160 900 900 September 1. 1964 2 x 12 1150 900 900 Western Wood _{2 x 4} ₉₅₀ ₉₅₀ ₇₈₀ ₆₁₀ ₆₁₀ Products Association _{2 x 6} 1~~0 11.?0 900 660 660

(WWPA) Standard _Standard _{2 x 8} ₉₆₀ ₇₆₀ ₇₆₀

Gra.ding Rules _{2 x 10} ₉₉₀ ₇₈₀ ₇₈₀ 1965 and Supplement _{2 x 12} ₁₀₂₀ ₈₀₀ ₈₀₀ January 1, 1966 Western Wood _{2 x 4} ₆₀₀ ₆₀₀ ₄₉₀ ₃₈₀ ₃₈₀ Products Association _{2 x}_(I ₉₅₀ ₉₅₀ ₇₈₀ ₅₆₀ ₅₆₀ (WWP A) Standard _Utility _{2 x 8} _{1070 1070} ₈₇₀ ₆₈₀ ₆₈₀ Gra.ding Rules 1965 and Supplement 2 x 10 1120 1120 920 720 720 January 1, 1966 2 x 12 1100 1100 900 710 710 11

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1.1.4.2.

TABLE IV

Grading Rule*** Grade Nominal Size'"

Species Groups and Allowable Unit Stresses in psi (inches) l(a) 1(b) l(c) II III IV

2 x 4 12~0 9~0 9~0 Select 2 x 6 _{2 x 8} 043-1953 Structural 2 x 10 C.S.A. 2 x 12 Specification for Structural Timber 10~0 8~0 8~0 Structural Eastern Spruce Grading Committee Rules as published 2 x 4 1160 910 910

by the Maritime _Selected 2 x 6 1280 1010 1010

Lumber Bureau and _Merchantable 2 x 8 1250 980 980

the Quebec Lumber 2 x 10 1220 960 960

Mfrs. Assoc. 2 x 12 1280 1010 1010

August 1. 1962

and 2 x 4 960 760 760

Canadian _No.1 2 x 6 1160 910 910

Lumbermen's _{( Construction)} 2 x 8 1150 900 900

Association Rules for 2 x 10 1150 900 900

White and Red Pine. 2 x 12 1210 950 950

revised edition January 1965 2 x 4 780 610 610 No.2 2 x 6 1020 800 800 (Standard) 2 x 8 1100 860 860 2 x 10 1120 880 880 2 x 12 1180 920 920 2 x 4 910 2 x 6 910 Canadian No.1 2 x 8 900 Lumbermen's 2 x 10 900

Association Rules for 2 x 12 950

White and Red Pine. _{2 x 4}

840 revised edition, _{2 x 6} 850 Jan. 1965 Merchantable _{2 x 8} 860 and No.2 _{2 x 10} ₈₈₀ 2 x 12 920

Committee Rules for _{2 x 4}

760 Red and White Pine

as published by the No.1 _{2 x 8}2 x 6 800

830

Maritime Lumber Dimension _{2 x 10}

880 Bureau and Quebec

Lumber Mfrs. Assoc., 2 x 12 900

effective August 1, 1962

Canadian Lumbermen's 610

Association Rules for _NO.2 660

White and Red Pine, _Dimension 680

revised edition 720

January 1965 760

Eastern Pine Grading Committee Rules for

610 Red and White Pine

as published by the No.2 710

760

Maritime Lumber Dimension

840 Bureau and Quebec

850 Lumber Mfrs. Assoc., effective August 1. 1962 12

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1.1.4.2.

TABLE IV (c) - Allowable Unit stresses in longitudinal shear and in compression perpendicular to grain and values of modulus of elasticity for the various lumber species groups in Farm Buildings, for normal

duration of load and dry service conditions.

*

Compression Modulus of

Longitudinal Perpendicular Elasticity

Species Group Shear, psi to Grain, psi psi

I(a) 120 460 1,600,000 I(b) 100 390 1,600,000 I(c) 90 360 1,600,000 II 95 330 1,200,000 III 90 300 1,100,000 IV 80 260 1,000,000

*See Clauses 1.1.4.2.(4) (a) and 1.1.4.2.(4) (b) for limitation.

**Spans for sizes not listed in the Table (2 x 5, 2 x 7, etc.), may be estimated with sufficient accuracy by straight line interpolation.

$UFor Grade Markings of Canadian lumber see Appendix D of Supplement No.6, "Residential Standards" to the National Building Code of Canada.

1.1.4.3. Structural Assemblies

-(1) Structural assemblies may be designed in accordance with the

relevant clauses of Section 4.3, "National Building Code of Canada", or

may be evaluated on the basis of load tests.

(2) Where the design of structural assemblies is based upon load tests, representative sample assemblies selected at random should be capable of supporting

(a) 100 per cent of design dead and live loads for one hour without exceeding deflection limitations where applicable, and

(b) 100 per cent of design dead load plus 200 per cent of design live load for 24 hours without failure.

1.1.4.4. Glued Structural Assemblies

(1) Glued structural assemblies including glulam, should be either exterior or interior grade as required to meet the service conditions.

(2) Interior grade may be used where the equilibrium moisture

con-tent in service will average 15 per cent or less over any year.

(3) Exterior grade should be used for all other service conditions,

including those buildings where the interiors are subjected to high

relative humidity or free water. SUBSECTION 1.1.5. UNIT MASONRY 1.1.5.1. General

Except as provided for in this Section, the design of unit masonry

should conform to the requirements in Part 4, Section 4.4, of the "National

Building Code of Canada".

1.1.5.2. Allowable Heights and Minimum Wall Thicknesses

(I) The minimum thickness of load-bearing solid masonry walls not exceding 36 ft. in height should be

(a) 8 in. for the top 20 ft.,

(b) 10 in. for that portion more than 20 ft. but less than 36 ft. from

the top,

(c) 4 in. for buildings measuring less than 100 sq. ft. of floor area and with superstructure walls less than 8 ft. in height, and (d) 12 in. for below grade walls extending more than 7 ft. into the

ground. 13

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1.1.5.2.

(2) The minimum thickness of load-bearing cavity walls not exceed-ing 25 ft. in height should be 10 in.

(3) The minimum thickness of non-load-bearing partition solid masonry walls not more than 12 ft. in height should be 4 in.

1.1.5.3. Lateral Support

(1) Every masonry wall should be supported at right angles to the wall face either horizontally by means of floor or roof systems or vertically by means of pilasters or crosswalls.

(2) The maximum distance between lateral supports should be (a) 18 times the wall thickness for load-bearing walls.

(b) 36 times the wall thickness for non-load-bearing walls. 1.1.5.4. Lintels

Concrete lintels should bear at least 8 in. on the wall on each side of openings.

1.1.5.5. Roof Anchorage

Roofs should be securely anchored to masonry walls to prevent lifting from high winds. Anchorage should be by means of anchor bolts of suit-able size. properly spaced and adequately embedded in concrete, or by other effective methods.

Reference should be made to Chapter 1 of Supplement No. 3 to the National Building Code of Canada for information on "Pressure and Force Coefficients for Wind Loads".

1.1.5.8. Mortar

See Appendix B Table B-1 for recommended mortar mixes. 1.1.5.7. Laying

(1) All masonry should be built true and plumb.

(2) Concrete masonry units should be dry when laid and each unit should be properly embedded in mortar. Joints should be tooled.

SUBSECTION 1.1.8. CONCRETE 1.1.8.1. General

Except as otherwise provided in this Section the design or appraisal of farm buildings or structural elements made from concrete or concrete products should be in accordance with Section 4.5, "National Building Code of Canada".

1.1.8.2. Air Entrained Concrete

Air entrained concrete should be used for all concrete that will be exposed to freezing and thawing and to the use of de-icing agents. 1.1.8.3. Ready-Mixed Concrete

Ready-mixed concrete should conform to the requirements of CSA Specification, "Concrete Materials and Methods of Concrete Construc-tion", A23-1, 1960 published by the Canadian Standards Association. (See Appendix B, B-II for guide for ordering ready-mixed concrete). 1.1.8.4. On-Site Mixing

See Appendix B Table B-III for recommended mixes for on-the-job mixing.

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1.1.6.5. Concrete Floors

(1) The minimum thickness of floors should be 3% in.

(2) Subgrade

(a) The subgrade should be free of sod, large stone, organic matter,

mud and debris and should provide uniform support under the floor.

(b) Fill material should be placed in 6-in. layers and should be well compacted.

(3) Joints

Floors should be prevented from bonding to foundation walls.

columns or other rigid parts of buildings. (4) Watertight floors

(a) An adequate vapour barrier should be laid over the subgrade.

Where strip material is used, a 4 in. lap should be maintained.

(b) In wet areas, a minimum of4 in. of granular material should

be placed over the subgrade followed by a vapour barrier as outlined in (a). Adequate drainage by means of drain pipe should

also be provided.

1.1.6.6. Concrete Pavements

(1) The minimum thi~kness of pavements should be 4 in.

(2) When drainage is required, a minmum slope of 114 in. per ft.

should be provided.

(3) Joints should be provided to control cracking.

1.1.6.7. Concrete Silo

1.1.6.7.-(l)

Foundations-(a) The minimum thickness of foundation walls should be 6 in. (b) Foundation walls should be reinforced to withstand the lateral

pressure of the silage.

(2)

Footings-(a) Footings should be designed to carry the weight and friction

loads of silos.

(b) For a vertical cylindrical wall centered on an annular footing of any type, the width at the base of the footing required to sup-port the wall and vertical friction loads is given by formula

w 12hl (12.St.

+

2.64hl1.08)

p

in which w

=

width of footing in inches at the base

hI

=

distance from top of silo to top of footing in feet

t

=

thickness of wall in inches

p

=

allowable soU pressure in psf.

(c) For a cylindrical wall centered on a plain annular footing, the depth of the footing should be calculated by formula

d

=

Vpw 131

in which p

=

allowable soil pressure in psf

w

=

width of footing in inches as calculated from

formula in (b)

d depth of footing in inches

15