The National Building Code - toward uniformity of building regulations in Canada

Publisher’s version / Version de l'éditeur:

Building Management, 6, 3, pp. 38-40, 1967-10-01

READ THESE TERMS AND CONDITIONS CAREFULLY BEFORE USING THIS WEBSITE. https://nrc-publications.canada.ca/eng/copyright

Vous avez des questions? Nous pouvons vous aider. Pour communiquer directement avec un auteur, consultez la première page de la revue dans laquelle son article a été publié afin de trouver ses coordonnées. Si vous n’arrivez pas à les repérer, communiquez avec nous à PublicationsArchive-ArchivesPublications@nrc-cnrc.gc.ca.

Questions? Contact the NRC Publications Archive team at

PublicationsArchive-ArchivesPublications@nrc-cnrc.gc.ca. If you wish to email the authors directly, please see the first page of the publication for their contact information.

NRC Publications Archive

Archives des publications du CNRC

This publication could be one of several versions: author’s original, accepted manuscript or the publisher’s version. / La version de cette publication peut être l’une des suivantes : la version prépublication de l’auteur, la version acceptée du manuscrit ou la version de l’éditeur.

Access and use of this website and the material on it are subject to the Terms and Conditions set forth at

The National Building Code - toward uniformity of building regulations

in Canada

Legget, R. F.

https://publications-cnrc.canada.ca/fra/droits

L’accès à ce site Web et l’utilisation de son contenu sont assujettis aux conditions présentées dans le site LISEZ CES CONDITIONS ATTENTIVEMENT AVANT D’UTILISER CE SITE WEB.

NRC Publications Record / Notice d'Archives des publications de CNRC:

https://nrc-publications.canada.ca/eng/view/object/?id=c1804ece-8150-4c49-839b-90ee6b2c0afd

https://publications-cnrc.canada.ca/fra/voir/objet/?id=c1804ece-8150-4c49-839b-90ee6b2c0afd

Ser

TEl

N 2 1 t 2 '

no. 251+

c . 2

BI,DG

NATIONAL RESEARCH COUNCIL OF CANADA

CONSEIL NATIONAL DE RECHERCHES DU CANADA

THE

NATIONAT

BUITDING

CODE

Toword

uniformity

of building

regulotions

in Conodo

by

Robert

F. Legget

/\l'l ALYU

ED

Reprinted from

BUILDING MANAGEMENT

Vol. 6, No. 3, March 1967

P . 3 8

Technical Paper No. 254

of the

Division of Building Research

OTTAWA

October

1967

NRC 9739

ilrur|luu

Price 10 cents

iltllllilll

_{e -- -2 ri ?z\,/}

()(JrCr-THE NATIONAL BUILD

NG CODE:

Toward uniformity of bu lding

regulations in Canada

Bg Robert F. Legget

Dhec'tor, Ditision of Building Research, National Research Council, Chai.rman, NRC Associate Committee on the National Build.ing Cod.e

CeNepe' is within sight of having vir-tual uniformity of municipal building regulations from coast to coast. Jlhis will eliminate one of tlle major ob-stacles to economy and efficiency in construction and should answer unin-formed statements that cite conflicting building regulations as the main

deterrent to building progress in Canada.

This advance toward uniformity has been achieved by the volrrntary adop-tion by municipalities of Canada's Na-tional Building Code. A recently pub-Iished report on the use now being made of the Code across the country shows that, at the end of 1966, just over 70 per cent of the urban population of this country lives in municipalities that are using the Code in whole or in part as their own building regulation

(Figure l). Over 90 per cent of the incorporated cities of Canada are using the Code. It is now mentioned by name in six of the provincial Acts that regu-late building and in addition has the support of the other four provincial governments. In the light of current progress with its further adoption, and if the steady trend in its adoption dur-ing the last eight years continues, the National Building Code will constitute the local municipal building regulation throughout almost all of Canada within the foreseeable future.

The Code/s odvisory nolure

The Code is an advisorv document

only, as published by the Nr search Council. Unless and

adopted by a municipality (ei whole or in part) as its own b regulation, it has no legal sl whatever. It is written in the I a bylaw to facilitate its local

Although published in a con looseleaf edition. it is also avai

hard covers with cloth

it is necessary to have it in this nent "book" form for legal Both forms of the Code and

l d u and the

l i n

technical Supplements are avai both of Canada's official langua Preparation of Le Code Nati Bdtiment involved a

extensive task of translation, out by the chief translator ot

Mort-gage and Housing Co4>oration. was kept of the many

terms that had to be translated.

due course they were combi unique dictionary - the Di.ctt Buil.ding T erms (Dictionnai.re m e n t ) .

This dictionary is a special dian contribution to

and is at work in many which English and French are technical work. (The Diction a publication of the National

Council although sponsored by tosether with C.M.H.C.

available from Les Editions

Montreal, at $9.50 a copy.)

The Code is not, as many think, a manual of building design. It is rather a set of mini,mum requirements to

which all buildings to which it applies must cpnform in the interests of the safety of the public. There are many aspects of modem building design that are not even mentioned in the Code, features that do not in any way affect safety in buildings. Those parts of the design process that are dealt with, al-though they may constitute guides to the prosecution of designs in the offices of architects and engineers, are still essentially those minimum provisions that must be adhered to. Changes that a designer may wish to make in his de-signs are quite within his jurisdiction just so long as he does not include any feature that violates the minimum re-quirements set out in the Code. In no way at all, therefore, does the Code place a "strait-jacket" around the de-signer, if the safety of the public be accepted as an essential basic require-ment by which all designers must be bound.

Con ihe Code be "nqlionol"? It is sometimes asked how Canada can have a truly 'hational" building code in view of the size of the counfy, local variations in building practice and especially because of the wide variety in local cJimatic conditions. Local building piactice is nof interfered with by the Gode providedi 4gain, that it does not violate the basfc.essentials of public safety. Local variations in design features dre almost alwals more strin-gent than ih"e :niinimrirn requirements of the Code. Re-it is r i n lle in since md in into a rg of

"In the llght of current progress,

and tf the steadg

trend in its adoption during the lnst eight Uea'rs

continues,

the

National Building Code usill constitute the local municipal

building regul,a,tinn

throughout almort all of Cana'd'a'

within the foreseeable future."

Climatic factors have always been recognized in the Code; the 1953 edi-tion included a set of maps of major feahrres of the Canadian climate. More recent editions have these same maps, suitably revised, in one of the technical Supplements to the Code.

This Supplement also contains a list of all major municipalities in Canada together with the essential climate fac-tois for each required for building de-sign (rain and snou{all, extreme tem-pJratures. etc.). This information has been derived from the extensive rec-ords of Canada's Meteorological Serv-ice. In the Administrative Part of the Code itself there is a table into which can be inserted the appropriate figures by any municipality when it adopts the Code for its own use. These climatic factors then become a part of the local building regulation, applicable only to that municipalitY.

Snow loads may be mentioned in more detail since they afiect the design of roofs on all buildings. After careful study, a new system for.evaluating snow loads was introduced into the 1953 edition of the Code. The new loads were arrived at by considering the maximum snowfall on record as re-maining on the ground in the month of March, to the weight of which was added the weight of the maximum rain-fall in March for the same locality, for it is conceivable that the two could be combined.

It was thought that these loads might be too conservative, and so the N.R'C. Building Management, March 7967

Associate Committee responsible for the Code requested the Division of Building Research of N.R.C. to find out if they were. With the willing aid of over 60 volunteer observers, the Division initiated a survey of snow loads on roofs all over Canada almost 10 years ago (Figure 2). Results ob-tained by these scientiffc observations after the first ffve years were such that the Associate Committee felt justified in reducing the originally determined average loads by 20 Pen cent, with greater reductions in certain special cases. When records for the l0-year period are available, further refinement may be possible.

This example illustrates the economy to all municipalities of having such a national model document available for their use, one that can be steadily im-proved by the results of research work by the national building research agency.

This reference to snow loads well illustrates the sort of requirement that the Code contains. Failures every win-ter of weak roofs under excessive snow loads show vividly how the safety of the public must be protected. All roofs should be designed for well-justiffed snow loads; all roofs designed for use in municipalities that use the Code are so designed. Loads upon structures are, therefore, one important tecbnical con-tent of the stmctural part of the Code. Other features in this Part are founda-tions and design Procedures with wood, masonry, steel, and concrete and

also for the cladding that is applied to the exterior of buildings.

Changes in popular types of building design make this last section exception-ally difficult to prepare. It will be drastically amended in the next edition of the Code.

Materials are naturally dealt with, but by reference to standard specifica-tions. Plumbing and Heating require-ments constitute two major Parts of the Code. Safety Requirements on Construction are also dealt with, this being another Part in need of exten-sive revision. Administrative Require-ments constitute Part 1 of the Code. "Use qnd Occuponcy"

The most important Part of the Code is that which deals with Use and Occu-panca> well known in building circles as "Part 3." This document provides a compilation of all the requirements for safe building design that are deter-mined by the use to which buildings are to be put, irrespective of the ma-terials of which tlley may be con-structed.

Hospitals, hotels, laundries - these and all other major groupings of types of buildings have speciffc requirements in their design that must be met if the safety of the publiois to be ensured. Fire preventive measures, exit require-ments, and provisions relating to pub-lic health, such as ventilation and light-ing standards, are therefore to be found here.

Although the present requirements are a great improvement over earlier standards, research and study are con-stantly proceeding in the interests of making Part 3 an even better document than it is at present. As but one ex-ample, the Fire Section of DBR/NRC visits many major fires in Eastern Can-ada to see what can be learned from them with a vierv to improving the Code fire-prevention requirements; this information is being provided to the Assoeiate Committee for its use. Enforcing good proclice

Part 9 of the Code is probably a unique document, for it is a true "per-formance type" of code requirement stating in general terms what resi-dential construction shall provide and how it shall perform. By itself, it merely gives the local authority the power to enforce good practice in residential construction.

The details of such good practice are set out fully in Supplement No. 5. This is a document of almost 200 pages that gives not only requisite minimum re-quirements fol house and apartment construction but other useful design re-quirements that may be necessary for sorne purposes. Central Mortgage and Housing Corporation uses this docu-ment as its own regulations for the control of all residential constmction under the National Housing Act which it administers. Previous duplication of requirements between the Code and CMHC standards have now been com-pletely eliminated.

The National Building Code is pre-pared and pdblished under the author-ity of the Associate Committee on the National Building Code of the National Research Council. This national group consists of 24 Canadians. leaders in all major aspects of the building industry and associated government agencies, each appointed by the Council as an individual and not as a representative of any interest, to serve for a 3-year term. Serwice is voluntary, the Council paying only traveling expenses to meet-ings when this is necessary.

Assisting the Associate Committee are 10 Standing Committees engaged on the constant work of revision. Each deals with a major technical field, and each is made up of about 20 experts in this ffeld, also serving voluntarily.

The Council's Division of Building Research provides technical and secre-tarial supporting services, but the As-sociate Committee is alone responsible fol all aspects of the Code. It always welcomes informed criticism and con-structive comments and suggestions. These should be sent to the Secretary, Associate Committee on the National Building Code, c/o National Research

=

o 6 0

i r o

o-i q o

o-1 9 5 9 6 0

6 1

6 2

6 3

6 4

6 5

6 6

6 7 1 9 6 8

Y E A

R

Figure 7: Progress in adoption of the National Building Code oaer the past eight gears (7967 estimated), shown as percentage of population.

d

Figwe 2: Ten gears ago,60 aolunteers undertook a straeV of moto loads on roofs all