Snow loads on roofs 1964-65: ninth progress report

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Snow loads on roofs 1964-65: ninth progress report

Faucher, Y.

SNOW LOADS ON ROOFS 1964-65 NINTH PROGRESS REPORT

by

Y. Faucher

. ANAl YIED

Internal Report No. 339 of the

Division of Building Research

OTTAWA June 1967

Snow loads on roofs vary greatly according to geo-graphical location (climate), site exposure, shape and type of roof, and, of course, from one winter to another. This vari-ability in roof loads and the corresponding uncertainty about

proper design values have been the main reasons for the extensive survey of snow loads by the Division of Building Re search.

Snow loads for design purposes are given in the National Building Code of Canada. In the 1953 NBC design snow loads were generally considered to be equal to the ground snow load which include s an appropriate value of the weight of a 24 -hr rainfall, with reductions allowed for sloped roofs only. The DBR survey on snow loads was initiated to provide the necessary in-formation on which to base a more refined as se s sment of the loads. In the 1960 revision of the NBC the roof load was set at 80 per cent of the ground load, the ground load being based on a return period of 30 years.

Further changes have been made in the 1965 Code which, it is hoped, will lead to an even more rational approach to snow loads for the design of roofs. The basic roof load remains 80 per cent of the ground load except that for roofs exposed to the wind a roof load of 60 per cent of the ground load may be used under certain conditions. At the same time allowance has been

made by means of "snow load coefficients" for a variety of influences causing accumulations of snow loads on roofs. It is the purpose of this ninth Progress Report of the Survey of Snow Loads on Roofs to continue the provision of factual information so that further con-sideration of the de sign roof snow loads in the National Building

Code of Canada, can be made by the Associate Committee responsible for the Code.

The Division of Building Research wishes to express, once more, its appreciation to all observers across Canada for the excellent work done in collecting data for the survey of the 1964-65 winter. In particular, special appreciation is recorded to A-Station observers of the Meteorological Branch of the Department of

Transport at Gander; the National Parks Branch of the Department of Northern Affair s and National Resource s at P;E. I. National Park; Ecole Polytechnique (Montreal); Laval University (Quebec);

Macdonald College [Ste , Anne de Bellevue); Oue eni s University

(Kingston), University of Toronto; University of Manitoba {Winnipeg}; University of Alberta {Edmonton}; University of Waterloo; Aluminum Company of Canada at Arvida; Mrs. p. Curtis at Inuvik; and the

Atlantic, Prairie, and B. C. Regional Stations of the Division. Thanks are also here recorded to the Chief of the Air Staff, Air Force

Headquarters, Ottawa, and to the R. C. A. F. personnel at C Stations at Comox; Lancaster Park; Cold Lake; Winnipeg; North Bay; Ottawa and Toronto, and to the building inspectors and individuals who

made observations at B Stations. Without all this willing co-operation

this survey could not have been carried out.

This report was prepared by Y. Faucher, graduate in Civil Engineering from Laval University, summer worker with the Building Structures Section, under the direction of W. R. Schriever. Ottawa

June 1967

Robert F. Legget Director

z

z

·

.

·

.

·

.

A Stations B Stations C Stations

SURVEY PROCEDURES OF 1964-65 OBSERVATIONS... 1

1

WEATHER... •••• ••• .•• ••.• ••••••• •••••• ••••••••• Z

PRESENTATION OF RESULTS... Z

·

.

A Stations

RESULTS OF THE 1964-65 OBSERVATIONS... • • • • • • • • • 3

4 B Stations

C Stations

·

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77

GENERAL DISC USSION. • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 8

Ground Snow Density •• • • • • • • • • • • • • • • • • • • • • • • • • 10

CONCLUSIONS. • • • • • • • • • . • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 10

by Y. Faucher

The Division of Building Research continued the survey

of snow loads on roofs during the winter of 1964-65. Generally the

survey was carried out in the same way and on the same roofs as in previous winters.

This survey was started in 1956 to provide the basis for refinement of the design snow loads given in the National Building

Code of Canada (1). The first report, in 1956, presented a

dis-cus sion of the snow load requirements in the 1c,53 National Building

Code and proposed a survey of snow loads on roofs. Since that time

the survey has been carried out annually with the help of many

observers across Canada. This report gives a summary of all

observations taken during the 1764-65 winter.

SURVEY PROCEDURES OF 1964-65 OBSERVATIONS

Procedures used at A, B, and C Stations for the 1964-65 winter season were generally the same as those used in previous

years (2, 3, 4). A brief description of these procedures follows.

A Stations

At A Stations detailed observations of snow depth and density on roofs and on the ground are recorded at least once a week

and always after a heavy snowfall. The depth of snow on the roof is

read at every snow gauge. The depth on the ground is taken as the

average of the undisturbed snow around or near the building. At

most of the 15 A Stations at least one flat roof and one gable roof are

observed. A total of 40 roofs were used among the 15 A Stations in

1964-65 (Table I).

The Stations at Wabush Lake and Goose Bay are not in-cluded in the report this year because no observations were available from them.

B Stations

Observations at B Stations are usually made after heavy snowfalls and are intended to give information on unusual

loads or structural failures due to snow. The observations are

made by building inspectors and other volunteers who assist the

Division in this survey on their own initiative. This year the

Division received 15 B Station reports presenting observations on

roofs of various shapes and sizes. One very important failure

occurred this year at Sarnia, Ontario, where a curved roof with a 200 -ft span collapsed under an unbalanced load re suIting from a single snow storm (5).

C Stations

At C Stations detailed observations similar to those taken at A Stations are carried out by R.C.A.F. personnel on

large roofs located at R. C. A. F. bases across Canada. The roofs

used for the survey were: arch hangar roofs (curved); mechanical

equipment garage roofs (flat, split level); cantilever hangar roofs (flat); and unit supply depot roofs (flat) (the last two had canopies

that were also observed). These roofs were all of standard size

and shape. Eighteen e oof s were observed at 7 C Stations in 1964-65.

WEATHER

Many parts of Canada experienced a winter season that

deviated considerably from normal. Most provinces had mean

monthly temperatures as much as 16 degrees below normal and

received as much as twice the normal total snowfall. Canada's

1964-65 winter was rigorous and gave interesting and useful in-formation for this present survey.

PRESENTATION OF RESULTS

Results of observations for the winter survey are pre-sented in the same form as those of preceeding years (6, 7, 8, 9, 10, 11) to ensure uniformity for future reference.

A Station results are given in detail for each roof by means of graphs on which ground loads, roof loads (minimum, maximum and average), and sometimes maximum canopy loads,

fresh snowfall in inches, maximum daily wind speed and direction, and mean daily temperatures are plotted against time. Plan and elevation views of roofs as well as orientation, size and shape of roofs, and locations of snow gauges on roofs are also given in Figures 3 to 17. The most important results from these figures are summarized in Table 1 and their graphical equivalents in Figure s 1 and 2.

B Station results are summarized in Table

ll.

Most of these observations are shown in a collection of case records (5).

C Station re sults are pre sented in a similar manner as the A Station results in Figures 18 to 24 and are summarized in Table III and Figure

1.

Table IV presents the comparison of the roof to ground load ratio for large flat roofs at A and C Stations.

In addition, Figures 3 to 24 show both the normal and the total snowfall within a stated period of time. Value s of snowfall are obtained from the Meteorological Branch of the Department of Transport. For a few stations from which the required meteoro-logical information was not available, records of the nearest station are used.

RESULTS OF THE 1964-65 OBSERVATIONS

Most parts of Canada had snowfalls during the past winter appreciably higher than normal. Observations from all the stations across Canada used for the survey show that the average total snowfall was 78.6 in. compared with the average normal snowfall of 63.6 in.

With such heavy snowfall one could expect this winter's ground loads to be very close to the design values cited in the NBC. Six maximum ground loads were observed that were higher than the NBC ground loads for the stations. Five of these were at R.C.A.F. Stations {C Stations} and the sixth was at Inuvik (an A Station).

This is about the number that one would expect in such a winter.

With a few exceptions, the average roof loads were lower than the 1960 and 1';65 NBC minimum design snow loads for roofs. The cantilever hangar roof at Lancaster Park, Alberta received an average roof load of 29 psf although the NBC 1965 roof load is 22 p sf , Twice during the winter the arch hangar roof at

exceed, the de sign roof load of 33 p sf', One drift that occurred on the arch hangar roof was three times the NBC design roof load. Altogether 9 roofs experienced maximum roof loads (drift Ioad s ] in excess of the basic NBC design roof loads.

B Station reports presented some interesting cases. Observations taken at Ridgemont School in Ottawa showed a drift of 182 psf, a load that was not only well above the basic NBC design roof load of 48 p sf , but one that exceeded the ground load observed at the time by a factor of 12! Many other cases have been recorded (5) •

The following comments on individual A, B, and C Stations direct attention to some cases of special interest with reference to the design of snow loads in the National Building Code.

A Stations

Inuvik, N. W.T. - Observations on the school building were not started until after 16 January because of the relocation of the school to a site about 200 yards northwest of the previous location. The direction in which the school building faced was also changed as can be seen in Figure 3.

This winter snowfall was well above normal but, as in previous reports, the roof loads were not very high. Maximum ground load was 33 per cent above the NBC ground load. Very little drifting appeared on the Federal Building because it has a flat roof but quite large drifts occurred on the leeward side of the gable roof of the Baetz Residence, due to prevailing NW winds. Temperature reached a low of _620

F.

Edmonton, Alta. - Because the snowfall for Edmonton was 85 per cent above normal, the maximum ground load was only a little below the NBC ground load (86 per cent ). The maximum average roof loads were low and little drifting was observed.

Maximum drifts occurred on gable roofs and were only 59 per cent of the NBC roof load.

Saskatoon, Sask. - SaskatoonIs snowfall was about normal. Maximum average roof loads were low except for the flat-roofed

Gymnasium with its 2-ft-high parapet wall. Maximum drifts occurred there that resulted in maximum roof loads just above the NBC roof load.

Winnipeg, Man. - Because Winnipeg received a total snowfall only 20 per cent above normal, the maximum average roof load remained far below the basic NBC design roof load.

Nevertheless, a drift of 25 psf (twice the ground load) was recorded on a sheltered gable roof but this is still Ie s s than the basic NBC design roof load. The maximum ground load was only 50 per cent of the NBC ground load, as would be expected in a near -normal winter. It is probable that high winds swept away some of the snow from the ground observation site during the winter.

W ate rIoo, Onto - At Waterloo the total snowfall was 78.9 In , , 70 per cent above normal. Yet, as would be expected from the statistical point of view, the maximum average roof loads were still below the basic NBC design roof load. A drift 60 per cent above the ground load, but still below the basic NBC design roof load, was recorded. This drift was on a flat roof exposed from east to west but partially sheltered in the north to south direction by roofs 12 it higher. The winds were high, especially from the west, which might account for the relatively small loads on the roof.

Toronto, Onto - As for most of the stations across Canada, 'I'o r ontots snowfall was above normal. As usual the roofs were almost bare during the winter. A few drifts twice the ground load were recorded but the se were still below the NBC ground load.

Kingston, Onto - Very strong winds were recorded in Kingston. These winds may be the reason the ground snow loads were small in spite of a snowfall 40 per cent above normal. This emphasizes further that reliable ground loads are difficult to obtain in wind-swept, built-up areas. Large drifts occurred on both roofs observed in the survey. A flat roof with a 2%-ft high parapet wall had a drift exceeding the basic NBC design roof load. This drift was observed at the beginning of December and was

6

times the ground load but only 5 per cent above the basic NBC de sign roof load.

Ottawa, Onto - After three consecutive winters with

snowfall below normal,

Ott

awats total snowfall was just above normal.

It appears that winds prevented large roof loads from accumulating.

On the flat roofs only 2 large drifts occurred. The se were caused by a parapet wall in one case and a higher roof adjacent to a lower roof in the other. Gable roofs received some snow accumulations that never exceeded 5 psf, but were bare most of the time.

Ste. Anne ､･｟ｉ＿｟ｾｉｊ･ｾｾｊ p.Q. - Again this winter, St e , Anne de Bellevue received little snowfall; total snowfall was only

66 per cent normal. In spite of strong west winds which kept roofs

almost bare, 2 drifts were observed just below the projections of higher roofs.

Montreal, p. Q. - Here the snowfall was 25 per cent below normal and ground load reached a maximum of 23 psf, still

well below the NBC ground load. West winds helped to keep

average roof loads low. No high drifts were observed.

Quebec City, P.Q. - Quebec's snowfall was 15 per cent

above normal. Unfortunately, ground load measurements were

taken only at the end of the season when a maximum ground load

of 30 psf was recorded. A large drift of 68 psf, a value just above

the basic NBC design roof load, occurred on the PavilIon Vachon

roof which is located between 2 higher roofs. The average snow

load on this roof was quite large, with a maximum average of 19 p sf , In contrast, the gymnasium roof received a maximum drift load of only 14 psf ,

Arvida, p. Q. - With a snowfall 25 per cent below normal for this region, large snow loads could not be expected. The observed roof loads were all below the maximum ground load

of

6

p sf', Most of the time the snow melted on the roof and formed

a thin ice cover. Snow and ice loads were much below the basic

NBC de sign roof load.

P.E.I. National Park - Total snowfall was just above normal in Prince Edward Island National Park where large drifts

were recorded on roofs and on the ground. The roof of the Central

Stores Building received a large drift of 48 p sf , a value just below

the basic NBC design roof load. The Registration Building was

surrounded by large accumulations; on the ground drifts were up to 48 psf , still below the NBC ground load.

Halifax, N. S. - A large total snowfall of 84. 1 In,.; 50

per cent above normal, characterized the winter season at Halifax. Halifax was swept by strong winds that caused large drifts on roofs

used for the survey. The NRC Laboratory and the Nova Scotia

Technical College roof received maximum drifts up to 25 psf , These drifts were less than the basic NBC design roof load, but occasionally reached 3 to 4 times the snow load on the ground.

Gander, Nfld. - As already mentioned, the total snow-fall acros s Canada was generally higher than normal. This was particularly true for Gander where the total recorded snowfall was 238.8 in. - nearly twice the normal. In spite of this, no large loads occurred on the roof used for the survey. This was probably due to strong winds that swept the region during the season. Ground loads up to 35 psf were recorded but this is below the NBC ground load. On the roof of the New Terminal Building, drifts up to 125 psf were recorded. These drifts which occurred on a well-sheltered canopy and in certain places beside penthouses were much above the basic NBC de sign roof load.

B Stations

Interesting results were obtained for a great variety of roofs observed in many parts of Canada. The reports from Rogers Pass and Glacier give considerable information regarding accumulations in mountain areas. A collapse in Sarnia caused by unbalanced snow loads is de sc ribed in another paper (5).

C Stations

Comox. B. C. - After having received a very large snowfall of 73.5 in. during the last two weeks of December, Comox Station recorded a total snowfall of 102.3 i n , , 180 per cent above normal. In spite of this large total snowfall, none of the observations were above the NBC loads. All roofs were exposed to strong winds.

Lancaster Park, Alta. - Lancaster's snowfall this winter was twice the normal. Large drifts occurred on both roofs used for the survey. One of them, observed on the cantilever hangar, exceeded the basic NBC de sign roof load by a factor of 3.

On the same roof a maximum average roof load 30 per cent above the basic NBC de sign roof load was recorded. Ground loads reached a maximum of 37 psf, about 30 per cent above the NBC ground load.

Cold Lake, Alta. - In spite of the fact that Cold Lake received a total snowfall below normal, large drifts were observed over the whole winter. The maximum drift recorded, 95 p sf , was nearly 3 times the basic NBC design roof load and 3 times the ground load observed at the time. These drifts were observed on the small flat roof at the foot of the arched roof. A maximum ground load of 42 psf, was recorded just above the NBC ground load.

Winnipeg, Man. - The main reason for the low snow loads recorded on roofs at the Winnipeg R. C. A. F. Station seems to be the strong winds that swept the region during the whole winter. Total snowfall was just above normal while the greatest drift was only 6 p sf , The same thing was also observed at Winnipeg A Stations where the winds swept the snow off the roofs.

North Bay, Ont , - Although the total snowfall was be Iow normal by 20 per cent, very large drifts were found at the North Bay R. C. A. F. Station. The snow accumulated to 83 psf on the lean-to roof adjacent to a higher flat roof. Observations were made on canopies of the U. S. Depot but the maximum drift was only 27 p sf , The maximum ground load reached 50 psf as compared with the NBC ground load which is 54 p sf ,

Ottawa, Ont , - Generally, at the Ottawa C Station drifts occurred on the three building s observed. The se were greate st on the Mechanical Equipment Garage where a drift load of 50 psf occurred.

Toronto, Onto - Because To r ontots snowfall was only 23 per cent above normal, snow accumulations were small. At the U. S. Depot the maximum ground load was 14 psf and on the building the snow drifted to 13 p sf , On the Mechanical Equipment Garage the drift load was 35 p sf , just above the basic NBC de sign roof load.

GENERAL DISCUSSION

The series of progress reports on the Divisionis survey of snow loads on roofs already provide considerable information that has been used to improve the approach to snow loads in the National Building Code of Canada. The information has shown that the average loads on roofs are generally considerably lower than the ground loads (except in unusually calm locations) and that drift loads which exceed the ground load by several time s occur in certain locations on

certain types of roofs. In an effort to provide guidance to designers in predicting drift loads on roofs appropriately, the 1965 edition of the National Building Code for the first time includes, in Supplement No.3, a chapter entitled "Coefficients for Snow Loads on Roofs. " The se coefficients are provided in order to help satisfy the provisions of Article 4.1. 3. 9. which states that the basic snow load coefficient for roofs shall be increased or decreased to account for the following influence s ;

"(a) The decrease of snow load because of the effect of slope

for roof slope s exceeding 300

,

(b) the accumulation of unbalanced snow load on gable and

hip roofs,

(c) the accumulation of nonuniform and unbalanced snow

load on arched and curved roofs,

(d) the accumulation of increased snow loads in valleys of

butterfly as well as multispan curved or sloped roofs,

(e) the accumulation of increased nonuniform snow loads

due to drifting snow on the lower of two -level or multi-level roofs, such as a canopy, marquee or porch roof provided the upper roof is part of the same building or of an adjacent building not more than 15 feet away,

(f) the accumulation of increased nonuniform snow loads

on areas adjacent to roof projections such as pent-houses, large chimneys, ventilating equipment,

(g) the accumulation of increased snow or ice loads on

areas due to snow sliding on to the se areas from an adjacent roof sloping towards this area or due

to melt water draining onto it. The magnitude

and distribution of the increase shall be appropriate to the relative portions and size s of the surface s , " In Article 4.1.3.10 of the National Building Code the basic snow load coefficient is retained at a value of 0.8 of the recommended ground load but for roofs exposed to the wind the

basic coefficient of 0.6 is provided if:

"(I) the roof is fully exposed to the winds on all sides,

i , e., is not shielded on any side from the direct

action of the wind by numerous trees higher than the roof or by higher roofs of the same or of neighboring building s,

(2) the roof does not have projections, such as parapet

walls, which prevent the snow from being blown off,

(3) the building is not located in a mountainous area with

heavy snow load and low wind speeds during the winter season:'

The snow load diagrams, given in Supplement No.3, cover the slope reduction on shed and gable roofs, distribution of snow on curved roofs, valley roofs, multi-level roofs, and on roof areas adjacent to projections and obstructions. One diagram also deals with the effects of sliding snow on a lower roof from an upper roof.

Ground Snow Density

The last progress report discussed ground snow density and pointed out that the present NBC ground snow loads were of the order of 20 to 25 per cent too low. This conclusion was reached after a statistical analysis of data on the ground snow density for 1957 to 1964. This analysis gave an average ground snow density of 0.26 gm/ c c ,

Records for this year were examined to see if they confirmed the previous conclusions and if it would be pos sible to

add further information in the Code for design NBC ground snow loads.

As one can see in Table V, information was obtained on ground snow density during the 1964-65 winter. For this evaluation 6 stations were chosen for which there were at least 15 observations of ground snow density.

The averages, for successive periods of 5 days, were plotted against time. This graph, presented in Figure 25, shows the ground snow density variations over the season from which some interesting observations can be made. For example, it can be seen that during January and February an average density of about 0.26 gm/ cc is appropriate. This is the same as the average for the whole survey period.

These results plus previous statistics indicate that an average ground snow density of about 0.26 gm/ cc would be a more appropriate value for the calculation of the NBC snow load than the value of 0.20

gmj

cc previously used. It may, however, be that the period used for the statistical analysis is too short and that a longer period of observations is necessary in order to develop reliable conclusions.

CONCLUSIONS

The conclusions that can be drawn from this winter's measurements are in line with those obtained in previous years. The observations confirm that average loads are small and that

drift loads are high. They also indicate that considerable care and experience is needed in selecting design snow loads to rna ke roofs safer than in the past without loss in economy. That such improvement is still needed is indicated every winter. Evidence, in the form of newspaper clippings and other reports on failures due to snow loads, continues to indicate that the past and, to some degree, the present understanding and use of snow loads is still unsatisfactory.

Primary steps have been taken toward improvement by providing shape coefficients for snow loads in a Supplement to the National Building Code and by varying the basic roof load depending on the exposure of roofs to wind. Further improvements, however, are needed in order to make the design snow loads still more

accurate and realistic.

It is suggested that this can be done only by improving the knowledge of designers in the field of snow loads. This requires a certain amount of understanding of the aerodynamics of buildings. Assistance to designers is being planned in two directions:

-(a) by providing a collection of case historie s of snow accumulations in Canada which may assist in suggesting better snow load assumptions for unusual types of roofs and, (b) by refining, in the future, the

basic coefficients of 0.8 and 0.6 depending on regional climatic conditions in Canada.

REFERENCES

1. National Building Code of Canada, 1965. National Research Council, Associate Committee on the National Building Code, Ottawa.

2. Allen, D. E. Snow Loads on Roofs, 1956-57. A Progre ss Report, National Research Council, Division of Building Research, Internal Report No. 134, January 1958, 7p.

3. Allen, D. E. Field Instructions for Observer s at A Stations of Snow Loads on Roofs. National Research Council, Division of Building Research, Technical Note No. 233, October 1')57, IIp.

4. Allen, D. E. Snow Loads on Roofs. The Present Requirements and a Proposal for a Survey of Snow Loads on Roofs.

National Research Council, Division of Building Research, Internal Report No. 106, September 1956, 19p.

5. Schriener, W.R., Y. Faucher, and D.A. Lutes. Snow Accumulations in Canada. Case Histories: I. National Research Council, Division of Building Research,

Technical Paper No. 237. January 1967, 29p. (NRC 9287)

6. Allen, D. E. and C. J. T'u r k str a , Snow Loads on Roofs, 1957-58. Second Progress Report of the National Research Council, Division of Building Research, Internal Report No. 163, November 1958, 6p.

7. Thorburn, H. J. and B. G. W. Peter. Snow Loads on Roofs, 1958-59. Third Progress Report, National Research Council, Division of Building Research, Internal Report No. 184, November 1959, l6p.

8. Watt, W. E. and H. J. Thorburn. Snow Loads on Roofs, 1959-60. Fourth Progres s Report, National Re search Council, Division of Building Research, Internal Report No. 204, November 1960, lOp.

9. Scott, J.F. and B.G. W. Peter. Snow Loads on Roofs, 1960-61. Fifth Progress Report, National Research Council, Division of Building Research, Internal Report No. 228, November 1961, l4p.

10. Hebert, P', A. and B. G. W. Peter. Snow Loads on Roofs, 1961-62. Sixth Progress Report, National Research Council, Division of Building Research, Internal Report No. 260, January 1963, l7p.

11. Allen, C. M. and B.G. W. Peter. Snow Loads on Roofs, 1962-63. Seventh Progress Report, National Research Council, Division of Building Research, Internal Report No. 279, November 1963.

R "A" STATIONS 1964-65

｟ＮＭｾＭＭＭｾＭＭＭＭ｟Ｎ ｾｾＭｾＮ｟ＭＭ

N'BC Roof (•• s, f.

1960 1965 1965 Max. Ground Max. Avg Roof Max. Obatd , Roof

80'!, 80'!, 60'" {p,s.I.) (p •••f.) (p, s.f.) 37 37 Z8 61 5 15 37 37 as 61 5 14 37 37 zs 61 3 6 II ZZ 16 l3 7 13 ZZ II 16 l4 3 5 zs zs II 33 3 6 Z8 Z8 ZI 31 4 5 Z8 Z8 ZI Z3 z 3 Z8 Z8 Zl as 5 8 zs Z8 II zz IZ Z9 36 36 zt zo 5 as 36 36 tt zo 5 8 48 48 36 ZZ 6 15 48 48 36 ZI 9 16 48 48 36 II 15 az l6 Z6 zo 4 l 3 3Z 3Z Z4 8 4 IZ 40 40 30 17 Il as rappt) 40 40 30 II 15 4Z 48 48 36 16 1 3 48 48 36 16 0 0 48 48 36 16 Z 4 48 48 36 16 7 Z8 48 48 36 19 6 8 48 48 36 18 II 30 43 43 3Z 17 I 5 35 35 l6 17 3 15 Z6 l6 zo 17 l 6 44 44 33 13 6 15 43 43 3Z ZO 8 18 43 43 az l3 9 II 67 67 50 30 19 68 67 67 50 30 6 14 60 60 45 6 Z 3 53 53 40 17 5 10 rth, 53 53 40 17 13 48 53 53 40 48 6 7 36 36 Z7 18 3 8 36 36 Z7 13 5 Z3 36 36 l7 10 9 Z5 50 50 37 35 5 1'; 50 50 37 33 Z 5 ｟Ｎ｟ｾＭＭ ｾｾＭＭＭＭＭ _..---- Ｎ｟ＭｾＮ｟Ｎ ｾ-ＭＭｾ - - - -Ｍｾ

Gable: He a ted , Insulated, Exposed.

Flat: Urthe at ed , Insulated, Exposed.

SNOW LOADS FO

Gable: Heated, Not Insulated, Sheltered.

Flat: Heated, Insulated, Exposed ..

Flat: Heated, Insulated, Sheltered.

Gable: Heated, Insulated, Expoaed ,

Flat: Heated. Not Insulated, Exposed.

Flat: Heated, Insulated, Exposed.

Flat: Heated, Insulated, Exposed.

Flat: Heated, In au l at e d, Exposed.

Gable: Heated, Insulated, Exposed.

Flat: Heated, Insulated, Sheltered from no

Flat: Unheated, Insulated, Sheltered {rom

east and west. Roof

Gable: 8/17 Heated, Insulated, Exposed.

8/1 Z Heated, Insulated, Exposed.

8/8 Heated, Insulated, Exposed.

Flat: Heated, Insulated, Exposed.

Gable: Heated, Insulated, Exposed.

ｇ｡｢ｬｴｾＺ Heated, Insulated. Exposed.

Gable: Heated. Insulated, Exposed.

Flat: Heated, Insulated, Exposed.

Flat: Heated, Insulated, Exposed.

Flat: Heated, Insulated, Sheltered

Gab le r Heated, Insulated, Exposed.

Gable: Heated. Insulated, Exposed.

Flat: Heated, Insulated, Exposed.

Gable: Unheated, Sheltered.

Flat: Heated, Insulated, Exposed.

Gable: Heated, Insulated, Exposed.

Gable: Heated, Insulated, Exposed,

Flat: Heated, Insulated, Exposed.

Flat: Heated. Insulated, Exposed.

Flat: He a ted , Insulated, Exposed.

Gablt": Heated, Insulated, Sheltered ..

Fht: Heated, In eu l at ed , Exposed.

Gable: Heated, Insulated, Expoe-ed

Flat: Heated, Insulated, Exposed.

Flat: Heated, Insulated. Exposed.

Gahle: Insulated, Sheltered.

Flat: Heated, Insulated, Sheltered.

Gable: Heated, Insulated, Sheltered.

Flat: He at ed , Insulated, Exposed.(Z'-6"pa

lnuvik, N. W. T. Station

Water loo, Ont.

Toronto,Ont, St eeAnne de Bellevue, Que. Edmonton, Alta. Winnipeg, Man, Ottawa, o-«, Saskatoon,Sa sk , Ktng aton , Ont , Montreal, Que .. Halifax, N. S. p. E. I. National Park Ar vtd a , Que. Quebec, Que. Ga nd e r , Nfld.

I

SNOW LOADS AT "Bit STATIONS 1964-65 NBC Roof

-Type Heated Major Influences (p.s.f.) Loads in P»s , f.

I of and Not Strong Heat Mild 1960 1965 1965 Avg , Roof I

I

I

Location Roof Insulated Heated Winds Loss Weather 80% 800/0 60% Ground Roof Drifts Remarks _I

!

Edmonton, Alta. Flat X 22 22 16 7 5 13 Parapet wall 4'_2" high.

Digby, N. S • Small

X X 38 38 29 6 ft of wet snow.

Slope

Vancouver, B. C. X 27 27 20 Snow load variations with

elevations above sea level.

Ottawa, Ont , Flat X 48 48 36 11 13 75 Drifts on lean-to sections.

Rogers Pass, B.C. Steep X 81 62 89 Sheltered.

Rogers Pass, B.C. Flat X 83 115 278 Flatroof adjacent to steep

roof.

Glacier, B. C. Gable X 129 129 97 125 70 120 Mountain area.

Ottawa, Ont , Flat X 48 48 36 16 27 182 Adjacent to a very large

flat roof (:::::: 380 feet)

Sarnia, Ont; Arch X X 24 24 18 13 96 10 in. snowfall in about 12

hours.

SNOW LOADS FOR "C" STATIONS 1964-65

Supply Depot Arch Hangar M.E. Garage Cant. Hangar NBC Basic Roof Load

ｾ

Max. Max. Max. Max. Max. Max. Max. Max. Max. Max. Max. Max. 1960 1965 1965

Ground Avg , Roof Drift Ground Avg. Roof Drift Ground Avg , Roof Drift Ground Avg. Roof Drift 80% 80% 60%

Station (p, s , f. ) (p,s ,f. ) (p,s ,f. ) (p. ssf , ) (p, s , f.) (p,s , f , } (p, s, f. ) (p; s , f. ) (p, s.f.) (p.s.f./ (p, s.f.) (p, s ,f. ) (p,s ,f. ) (p. s , f. ) (p ,s ,f. I I IComox, B.C.

-

-

-

24 9 20 26 6 12 28 7 17 46 46 34 I

I

I ILancaster, Alta.

-

-

-

-

-

-

35 14 47 37 29 69 22 22 16 I I I I

ICold Lake, Alta. 42 11 24 35 33 95

-

-

-

33 13 34 33 33

I 25 i I !Winnipeg, Man. 0 0 0 0 2 6 0 0 0 0 0 2 36 36 27 i I

INorth Bay, Ont, 50 8 14 25 34 67 33 8 83

-

-

-

43 43 32

I

\Ottawa, Ont,

-

-

-

35 17 39 55 9 50 30 11 38 48 48 36

I

Toronto, Ont , 14 5 13

-

-

-

13 7 35

-

-

-

32 32 24

Location Roof

...--- ---

---Inu vik , N.W.T. Comox, B.C.

Lancaster, Alta.

Cold Lake, Alta.

Saskatoon, Sask. Winnipeg, Man.

W ate rloo, Ont ,

North Bay, Onto

Toronto, Ont , Ottawa, Onto Quebec, Que. Arvida, Que. Post Office Arch Hangar M.E. Garage Cant. Hangar M. E. Garage Cant. Hangar U. S. Depot Arch. Hangar Cant. Hangar Gymnasium Library U.S. Depot Arch. Hangar M. E. Garage Cant. Hangar Main Engineering Bldg. Engineering Bldg. U.S. Depot Arch Hangar M.E. Garage U.S. Depot M.E. Garage Arch Hangar M.E. Garage Cant. Hangar Gymnasium PavilIon Vachon Rolling Mill

---1---

ｾｾ｟ＮＭＮ｟ＭＭｾ

Max. Average Max. Ground Roof Load

100

Roof Loads Loads Ground Load x

(P. s , f.) (p, s.f.) (per cent) - - - - -Ｍ Ｍ ｾ Ｍ Ｍ --- - --Ｍ Ｍ Ｍ ｾ 3 61 5 8 25 32 6 26 23 7 28 25 14 35 40 30 35 86 11 42 26 33 35 94 13 33 39 12 22 55 5 20 25 0 0 0 0 0 0 9 21 43 15 21 71 8 50 16 29 24 121 8 68 12 5 14 36 7 13 54 17 35 49 9 55 16 11 30 37 6 30 20 19 30 63

J

6 17

DENSITY VARIATIONS AT "Au AND "C" STATIONS 1964-65

I

I

Inuvik Lancaster Edmonton Cold Lake

I North Bay Gander

Dates !N.W.T. Alta. Alta. Alta.

_I

Onto

nne,

Averages

i

I 15 - 20 i

-

-

_0.106

-

-I O. 158 0.132

.

_{I I} :> _{20 - 25 0.130 0.142} I 0.136 0 I

i

-

-

-

i

-

I Z _{25 -}

ＳｾＰＮ

₂₀₅

_-

_0.118

_-

_-

_I

-

_{0.161 j}

j---I

0.132 0.210 I 0.185 I 1 - 5

I

0.180 0.220

-I

-I

I-< 5 - 10 I 0.310 0.243 0.190 O. 145 0.220 Q)

-

I

- .D-10 - 15 0.180 0.340 0.193 0.140 0.213

,

S

I

-

-Q) _{15 - 20 0.270}

-

_I

0.239 0.250

-

0.265 0.256 u

I

Q) 20 - 25

-

0.320 0.208 0.266 0.249 0.278 0.264 0 25 - 31 0.285 0.340 0.241 0.260 0.326

-

0.290 1 - 5 0.280 0.330

-

0.280 0.290

-

0.295 >. _{5 - 10} ! _0.245

_-

_0.173

--

0.206 0.208 l-< rtl _{10 - 15}

-

_{0.340 0.213 0.266}

_-

_{0.370 0.297} ;:l c:_rtl 15 - 20 0.210 0.320

-

0.306 0.150 0.285 0.254 >-:l _{20 - 25 0.250 0.320 0.253}

-

_{0.220 0.215 0.251} 25 - 31 0.190

-

0.217 0.290 0.250 0.460 0.281 1 - 5

-

0.300 0.211 0.286 0.223 0.290 0.262 >. _{5 - 10} 0.230 0.310 0.140 0.266 0.306 O. 1 6 0.241 I-< 0.316 0.284 et _{10 - 15 0.225 0.340 0.257}

-

-:l 0.272 0.280 0.120 0.224

ｾｉ

20 - 2515 - 20 0.2',0

-

0.400

-

_-

0.300 0.266

-

0.240 0.2,q

I

25 - 28 0.230

-

0.239

_-

-

-

0.234 1 - 5

-

0.390 0.287 0.273 0.286 Q.413 0.3Z:-5 - 10 0.275 0.370

_-

0.346 0.3()6 0.365 0.350 ..c

I

0.371 u _{10 - 15 0.280 0.350 0.350}

_-

_{0.370 O. 508} I-<

I

r:: _{15 - 20 0.255 0.330 0.346 0.420 0.233 0.316} ｾ

-I 20 - 25

-

0.330 0.337 0.273 0.283 0.321 0.308 25 - 31

-

0.320 0.310 0.316 0.346 0.2:;3 0.317 Averages 0.233 0.330 C --,6 0.281 O. 27 0.282 0.258

LOADS IN LBS/SQ FT !1964-19651 MAX. AVG ROOF LOA D LEGEND 80

n

1 5 10 65 : 55 MAX. 40 45 GR0 UND 30 35 LOAD 20 25 10 ｉｾ /

/

/

/

/ FIGURE 1

A&C STATION LOCATIONS AND THEIR MAXIMUM AVERAGE ROOF & GROUND LOADS FOR THE WINTER 1964-1965

3 SASKATOON 4 WINNIPEG 5 WATERLOO _ｾ 6 TORONTO 7 KI NGSTON 8 OTTAWA 9 STE-ANNE DE BELLEVUE 10 MONTREAL 11 QUEBEC 12 ARVIDA

13 P. E.I. NATIONAL PARK

14 HALl FAX 15 GANDER NO. C-STATIONS 16 COMOX 17 LANCASTER 18 COLD LAKE 19 WINNIPEG 20 NORTH BAY 21 OTTAWA 22 TORONTO

"'T'I - l J> 0 < ;:0 (;")

ｩ

..1

ｾ ＭＭ Ｍ Ｑ

r···J

I

ｾ

111111I

:::!::::

!

ｾ

;

[fir-- __

j.J

ｾｾｉ

----:...

ｾ

-_-_-_-_-_:J

6§_,

E_.1

'I

ｾ

ＭＭＧＭＭＭＭＭＭＭＭＭＭＭＭ ｉ

---

-.,

:::-.:::::::1

I , QUEBEC ARVIDA

I

I

ｾａｾ ｾＮ

NATIONAL

ｩｌｩＺＭＺＺＺＺＭＺＮＭＺＮＺＭＭＭＭｾ

HALl FAX

E-=·,

_____ 1,

- _ ... _..t

GAN DER

i-.----J...:...---=-j--....;....---,

STE-ANNE DE BELLEVUE MONTREAL KINGSTON OTTAWA WATERLOO TORONTO WINNIPEG SASKATOON INUVIK EDMONTON

s:

"'T'I J> _(;") X _c:

s:

;:0

_..,.,

c:

s:

N r-0 J> 0 V> J> - l

=

J>

=

V> - l J> - l 0 Z V> ... -0 0-.c.. I ... -0 0-\J1

·

LL.

·

VI

·

c.. _{NUMBER INDICATES ;'} GAUGE LOCATION / OF MAXIMUM _I" I I

...

...

,

,

,

,

---TIME, DAYS LEAN-TO ROOF

ETC.

MAXIMUMl_{LOA D} ON AVERAGE MAIN ROOF MINIMUM

FEDERAL BLDG MAXIMA AT#I 40 -20 60 N I - "'-it- ₄₀ ca et Cl ...J 20 BAETZ RESIDENCE FEDERAL BLDG

(EXPOSED, HEATED, INSULATED)

---I

.

I

_f

H=30' ,...,3' ,

ｅｊｽｾ

140' I ;

j

BAETZ RESIDENCE

(EXPOSED, HEATED, INSULATED 4"j

; I ｾ liB' ｾ , ｾ 4 i18' _1 _ll _ r.---SNOWFALL (NOVEMBER - MARCH) NORMAL 1964-65 34·2" 39·6" SCHOOL BLDG

(EXPOSED, HEATED, INSULATED)

Ｎｾ

•

\

FIGURE 3 12 - -- Ｖｾ

OJ

ｾ

T

.

I ..l MARCH FEBRUARY -- t I I : i I

ｦｾ

ｖｾｾ

l

!

,r--r "\

0

I I 1"i,/"J

1

I l ,

ｾｾ

-+.

---j--...tr ｾＭＭＭＫＭＭＭＭＭｬ '10 7 . I '1 ....-t. ! !:.' I " . ｌＭｾＧＭＭＭＮＮＮＬ I ' i --- ---i---+---t-- ----+,---1

,

ｾ］ｴ｜

L ---- ---+---- I i

ＮＮＮｲＭｾ

+

-+-_ _

NOVEMBER DECEMBER JANUARY SCHOOL BLDG.

MAXIMA AT_S

LOCATION AND DIRECTION

HAVE BEEN CHANGED

o 60 20 -- -40 --o SO -0 50 ｾ 32 ;;;: :.--Cl a.. z

,.

₀ et .... .... I

-,.

-40 '" UJ :I: u ｾ .J 120r-' ...J ｾ 3' 0 z '" 80 ---Cl UJ I-et ...J ::> :E 401--::> u u er 1--- 0 60

v

vv

SNOW LOAD OBSERVATIONS ON ROOFS Year: 1964-65 Location: INUVIK, N.W.T.

60 y -40 ADMINISTRATION 8LDG. _{Administration Bldg.} N

...

J ..•3 •• 9' ＧＭｉＭＭＮＭｾＮ Exposed

ｬｾ

1 Heated 5/'6

J

Insulated ; . L - - - I I - t----! 4 4> r I, MINING SHED 60 -N I-... ｾ 40 <> <[ 0 ...J 20 , 0 FIGURE 4 SNOWFALL (NOVEMBER-APRIL) NORMAL 1964-65 47·6" 88·3" Mining StoreShed N

..

1 ISheltered, Unheated Bldg.)

45r:'CJ

.1' l L APRIL NOVEMBER <n u.J :I: U ｾ ...i 120 ...J <[ u, ｾ 0 Z vv ₈₀ <> u.J I-<[ ...J :::> ::It ₄₀ :::> u u <[ Q 60 _N <>

W+E

Z ｾ 40 s j; ｾ :3!

«

_<> >< <[ :. ｾ :t « <> _a. z :. 0 <[ _u.J u.J I-::It -40

SNOW LOAD OBSERVATIONS ON ROOFS Year: 1964 - 65

Location: EDMONTON, ALTA.

40 I 133-IOFH. STREET ! / ."...., " '--..., I _{, , /} 20 ....-ｾ ,, ,-1'/ _N ｾ

-'-:;----./ ,I

133 - lO7lh SI.

..

0 Ｌｾ -60 I /2 I -ｾ 3 -

---.

'r==r

4_ _{ＲＴｾＢＬＢ} I • I -5 , /0 7-__---.1.. . -"- ,E_ _t 40 45'-0."' ｲＭＮＭＭＭＭＮｾｾ

'"

314 LAKE CRESCENT » > : _{(Exposed. Healed. Insutatedi}

I- - - ' LL. _i

---*'

20

--

...-,-...

-0 1_ ... ｾ " .

-et

----_.../

0

..

ｾ - - - - I 7 0 7 _{314 Lake crescent} 60 _ｾＭｲ /2

-

/ -3

Ｔｄｾ

ｾ

_4

37' 40 --- -5 7-_G. .B- ----l

OUTDOOR TEST STATION

_---

21. ____..;.,

20

---

(Exposed, Healed. Insulated)

I

_---9".

,-

---

---0 1.--- 9 Outeoor N

•

Test Station I_I I I _{.! -4}

.71-

r I

C-r/

3 , I .7 - .5 • 81 74 '

NOVEMBER

DECEMBER

JANUARY

FEBRUARY

MARCH

_ i .J • (;,

·:1I-l

!3 ｣ ＼ Ｍ Ｍ ｾ Ｍ ｟ .30' :E: ｾ

.s

120 ...J If

,.

0 z V> ₈₀ Cl

...

I-et ｾ :::> 2 ₄₀ :::> u u / et _J ..-0

r----60 0 z .

"

i ｾ 40

ｗｾｃ＿

ｾＺＺｉｉＡ N , ¥

'"

.

"-40

W+E

Ｑｴｾ

k:,

0 ... 5

... '*'

SNOWFALL ... _...

---

Ｌｾ X ( l . 20 etv>

ｉｶｦｾ｜

'rV'w

_ｾｖ

ｬｊｾ

ｖｖｾ

(DECEMBER-MARCH) 2 NORMAL 1964-65 0 27·8" 31'2' 50 ｾ LL. 32- - -

f\

---.v:

-et • .A

r'\

ｾ

r'\r

0 (l. Z 2 0 et ...

J ｾ

"vJ \-

u«

'I

V

ｾ

FIGURE

5(a)

ｾｉＭ

-40

SNOW LOAD OBSERVATIONS ON ROOFS

Year:

Location:

1964-65

SASKATOON, SASK.

NRC Lab. i I.

---I

_....----4---_

! ,_1--L " , . - - - _...

--r'

ＮＮＮ＿ｾ 20

t-I

I

60I---L---- - - + - - - - -ｾＭ N.R.C. LAS...MAXIMA AT #1

I

40 r - - - , - - - ---I---+---j I ! o

----eo

'" I-

"-W

60 r-r-:- --- _.- - ---'---+---+---+---1 ) ' 1 .38 I' ＭＭｾＭＭＭＭ --.I .1 .4- _7·

---.

.2 .7 8. 14-.3 .,;; J. _----.i Gymnasium Detai I A (Exposed, Heated, I nsulatedl

I

I I I I

Ir---

Ｇｾ

_

ｾ

Ｍ - ｾｾＭ i _ _ ' I ｊＬＮＮＭＭｾ

:

----,

' ,---GYMNASIUM

o

201---+ 401--- ----,--- + - - - f - - - - + - - - I e eo: o ...J ---+---+---.'J 4-. I';;2

NOVEMBER DECEMBER

JANUARY

FEBRUARY

MARCH

FIGURE

5(b)

SNOWFALL (DECEMBER -MARCH) NORMAL 1964-65 27·S" 31'2" 5. , • h

Exposed, Heated, Ventilated

2'Parapets 1--- t 1--- 1--- 1--- 1--- 1--- 1--- 1--- 1--- c -V) W :I: U ｾ

.:

120 ...J ｾ ｾ 0 z V) SO l-e w I-eo: ...J ::> :::E 40 ::> u u eo: -40 >-ｾＢﾭ eo: • e z ｾ 0 eo: w ｾｉＭ

SNOW LOAD OBSERVATIONS ON ROOFS

Year:

Location:

1964- 65

SASKATOON. SASK.

,

•

_I/ _• 413 ＮｾＭＭｾ • ｾＺＺｪ L

-.

4 j . : .8 ·5 2· ｾＱ ｾｉ . 1 • G /

.

_J'o/\i 771_c;. I '}' I ＱＭＭＧＭＭＭＭＢＧｌＮｩｾＭｾＭ -j

South Wing of Library

New Crop Research Bldg. 12' Above Roof . / SNOWFALL (DECEMBER- APRIL) NORMAL 1964-65 38·6" 45·9"

FIGURE 6

Agricultural Eng. Bldg.

Sheltered Attic Unheated, Ventilated, Insulated Exposed, Insulated, not Ventilated, Unheated Air Space

APRIL MARCH

ｾＭｾＭＭＭＫＭＭＭＭＭＭＭＭＭＭＭｬ

I I ! t : f --

,---

ｾ

•

ｾＭＭＭＫＭＭＭＭＭＭＭｬ

! I JANUARY FEBRUARY

ｾＭＭＭＭＭＭｾＭＧＭＭＭＭＭＫＭ

AGRICULTURAL ENG. BLDG. SOUTH WING OF LIBRARY

I I

---t---

J I DECEMBER

o

601---"'"'---' 120I---f____ -' if ｾ o z <J) 80ｉＭＭＭＭＭＭＭｾＭＭ o "-' l-e( -' => ｾ 40 u u e( 60 40 20

o

7 8 I 80 1-_.... ｾ 60 -0 e( 0 -' 20 o ｾ :.: 40 ｾ c, ｾ :::E ;:;:6 0 " - ' x ｾ 20ｉＭＭＭｉＫＭ｣ｬｴｬＭＭＢＧｯＧｴＭｩＫＭｴＧＭｴＫＫｾｦ ＭＭ｜｣ＭｲｬＭａＭｉＭＭ｜ｬＭＭＭＫＫＭＭＭＭＭＭｪｾｬ｟ｈａｩ｟ＭＫ｟ｊｉ｟ａ｟ＭＭｲＭｉ｟ｬＫ｜｟｟ｈｊｉｴＫｉ｟ｕ｜｟Ｋｉ｟｟ｉ e( <J) ::E >-== u, e( • o ｺｾ Ol-t-+=-e( "-' ｾ I--40

SNOW LOAD OBSERVATIONS ON ROOFS

Year:

Location:

1964-65

WINNIPEG, MAN .

20 ---254 Sunview I 3

8

.2 4.

"

1'5

.

7"

.

, "'3.8'-10"i ---;

(Heated, Insulated, Exposed)

401---,---

-+---l----j

I ! !

ｬＭＭＭＭｾＭ

!

/8\t

! 8 / \ "-.!. ...ｾ...-, / \-, - - - ... J. ... MAIN ENG. BLDG. Cl <X o -' 40 20 40 20

I

!r. :, \ ./ \

,t \

ｲ｟ｾ I 3 ...',., 3 \ / ,

--

---- \"---' ENGINEERING BLDG. 7 8 7 .L. Main Eng. Bldg.

z •

j

14';-r- -_.

(Heated, Insulated, Exposed)

if -G r----ｾ

(Heated, Insulated, Exposedl

7

1964-65 7B'9" .3 NORMAL 46· 3"

FIGURE

METEOROLOGICAL DATA FOR KITCHENER, ONT_ WIND DATA FOR' LONDON. ONT.

SNOWFALL (DECEMBER -APRIL) ｾ ｌ Ｍ

I

A-A Engineering Bldg.

-z.

APRIL MARCH FEBRUARY I

----t----

ＭＭｾ

..

ｾ

I

--- I

ｉｾ

DECEMBER JANUARY

SNOW LOAD OBSERVATIONS ON ROOFS

Year:

1964-65

Sheltered Bldg. Heated Attic Unheated Cei ling Insulated

21 Douglas Cres

•

/2

\

D-·I

-

/ :,

-

! " _ｾ (,- ₂₄ /8 I '3 7-_L _4 8_ ｾ .

---"---

l

ｾ

__

ＫＭＭＭｾＭ

I I

t - - - j

II DOUGLAS CRESCENT 20 60 16 0 -o <l: o -' 21DOUGLAS CRESCENT 11 Douglas Cres 40 20 o _ . _

-j

. .+,,_c,.

I z-2L

iD

l'U

-7 -'" 9-33 - ·i -.5G. I 3 I ? • L- f

-(Sheltered, Heated, Insulated)

NOVEMBER DECEMBER JANUARY FEBRUARY MARCH (f) .... :I: U ｾ

.:

120 -' <l: u.. ｾ 0 z en ₈₀ 0 ,_I

....

! I-<l: I -'

r

::::> ::l; ₄₀ ::::> u

r

u <l: 'J Ｍｾ

r

I 1-- _ . -60 o ｾ or: 40 ｾ a. ｾ ｾ

«

0-o ....

_....

ｾ 3; 20-::l;

ｾｾ

>i--- --

ｾｾＭ［ｩｉＧ｜ｾＭＭＭＭＭ

a.

ｾＭ｜ｌｾｾ

I ｾ ｾ 0 - I - ＭｾｦＭＭＭｾＭＭ ;

-ｾ

I- Ii Ii -40 SNOWFALL (DECEMBER-FEBRUARY) NORMAL 1964-65 37· I" 49'0"

FIGURE

8

SNOW LOAD OBSERVATIONS ON ROOFS

Year:

Location:

1964-65

TORONTO, ONT.

_.R

60 -- - - ＭＭｾＭＭＭＭｉＭＭＭＭＭＭＭＭＭＭ･ＭＭＭＭＭＭＭ

-+---26 EDGE HILL 40 - ---- - - , - - - + - - - '---r---1 60 - - - - ---i---+---I---I 40 --- - ＭＭＭＭＭＭＬＭＭＭＭＭＫＭＭＭＭＭＭＭＭＭＭｾ｣ＭＭＭＭＭＭＭＭＭＭＭ McNeill House 26 Edgehill /4

7V

40' , I

ｾＭｲｯＮ

ｾＮｬＬ

ｌＭｊｾｾｩ

Sheltered '

Attic not Heated •

Bldg. Heated ' Insulated ｾ 7

1\

ｾ｜

-=:\J

McNEIL L HOUSE o I 20ｾＭＭＭＭＭ｟ｴ｟ＭＭＭＭＭ｟Ｋ｟

ｉｾ

20 o eo: o --'

jr---+----/

---+---:=-/-+----ｉｾＧ

ｾＭＭＭｬＧ

NOVEMBER DECEMBER JANUARY FEBRUARY

...

N

I

• I .4 i 7· _% • Z . j _{.8 •i} I H,4o, ! . j .",

, .1

_1-ＮＳＷＢｾ

r

: _I i Exposed Insulated Attic not Ventilated Attic not Heated Bldg. Heated Parapet 2'6" MARCH I t L --11- -U> W :I: U ;z --' 120 --' ｾ ｾ o ;Z U> 80 o w I-eo: --' ｾ :::l: 4 0 -ｾ u u eo: SNOWFALL (DECEMBER· MARCH) NORMAL 1964-65 57'0" 79·8"

FIGURE 9

!

"

0 60 0 ;Z :i 40 ｾ a.: ｾ :::l: <i c:i 0 w w 20 x C. <I U> :::l: 0 ｾ - u, eo: 0 o c. ;Z :::l: <l _w ｾ I--40

SNOW LOAD OBSERVATIONS ON ROOFS

Year:

Location:

1964-65

KINGSTON

l

ONT.

40 I 20

+----

--A ...,-",..., -", I r , 0 4.-/;" 72 Bishop Blvd. f---60 I 40 BARKER BLVD. 11

"V

'

40

ｾＭ

I

1---

---_.

U

ｾＬＬＭＭ

ｴｾｲｂﾷ

...

10 -2 4 - , .... ., L .1 " . N

"-ｾ 20 I (Exposed, Heated, Insulated2"1

Cl

1

r-.>; « -' v , 0

r

12 • ....J _,--'

"[7'"40

Barker Blvd. - c , 0 I _ . - - - - . _ -f - - - ｑｾＮ Ｍ［ｯＭｾＭ _"" 60 I 1

8

1

,- ' , ' 7 -D. B. R. 10' . 24 •.•'2 4-! . 40 . - L....L .1

3--,

1 - - - _{(Exposed, Heated, Insulated2")}

I ! I 2

z.--

-

_-5': I ｾ .., I ,

-t

2

ｺｾ

I OBR

'E

20f - - - .- -- .

I

-\

ｾ

I . .,' ;, 3' ; ' ' ' '

,-

J"'; ,.

I I ｾｾＧＭｾ

ｾ

0 i I ｾＭＱ

ｾ

Jll

I • 7 ｾＺｊＮ ! •.'0 I

I (Exposed, Heated, I nsulated I

I

NOVEMBER DECEMBER

JANUARY

FEBRUARY

MARCH

en I L.,l I :x: u _I ｾ I

.

₁₂₀ ....J I ....J ｾ ｾ 0 z , en ₈₀ .-f 0

1 /

1 L.,l ...._« 1 ....J ;::>

r:

_I ｾ ₄₀

.r

;::> I U I U « 0 ; 60 0 I ｾ :i 40 - - -

...

ｾ a: N

ｾ

_J

ｾ ::Ii

W+E

ｉｾｾａ

:;;;:ci

ｉｨｔｾ

ｾｲ｜ｾ

..

ClL.,l s

.. f

A

ｬｾ SNOWFALL L.,l ｾ B; 20

iVVVV'lJ

YVv-J lIYV

ｾｾｾ

(NOVEMBER- MARCH)

ｾ NORMAL 1964-65 0 82·1 " 82· 7" 50

ｾ

>- 32f f

-VJV\

ａ｜ｾＭｾｪ

ｾＢＭ « • 0 , , -z ｾ 0

V

y

FIGURE IO(d)

« L.,l ｾ

....

-40

SNOW LOAD OBSERVATIONS ON ROOFS

Year:

Location:

1964-65

j'L

2 '

4 '

Exposed Unheated Air Space Ceiling Insulated 14"1 54 Heated Bldg.

Flat: 10' to Eaves

L

, 7

Fai maven Way Davidson Cres. 'II /2' ---. , .s 1 10 'C; 5,

.z

3 4 ＧＭＭＭＭｾ ＱｾＵ • I) , r-, '>-• /1 ,17 14, Hｾ ｾＧ 12 • /0 , 113 - - - , - r .Ib 15 FAIRHAVEN WAY

- - I

-+

! I ｾ i 7 '

_;AR:=t__··

_.-_-_/-+ -+-_ I ! . _ j - - - + - - - - + - - - I ! I 20 - - - - . - + - - - -

ｉＭＭＭｾｾｾ

ｾＭｾＭＭｾＭｾＯＡ

\

I 40 --0 60 40 " I-u, 1i;:- 20 0 « 0 --J 0 60 40 20 0

(Sheltered, Heated, I nsulatedl

FEBRUARY I 313 SNOWFALL (NOVEMBER - MARCH) NORMAL 1964-65 82·1" 82·7" 33 L_-"'L.._...

FIGURE 10 (b)

(Exposed, Heated, I nsulatedl 40A Barker Blvd. /2

-z-.-

I I} c::::=-- I «!!,

-r:==:==-r..

f - - - i

--c==J __

f

MARCH

.1-NOVEMBER DECEMBER JANUARY (f) lJJ I :r u ｾ

ｾＭＭ

. ₁₂₀ --J --J I Lt ｾ 0 I z I (f) ₈₀ _.

--I

0 lJJ I l-I « --J :::> ::< _{40 I} :::> u u « 0 ＭＭｾ 60 1 I 0 I z :r ₄₀ I ｾ a: ! >- _::l'i N --J

w+£

« o· 0 lJJ S X lJJn, ₂₀ « (f) ::< 0 50 >- 32 - -Ｍ Ｍ ｾ Ｍ ｾ - - - - ---J u.. «

.

0 z "-::< 0 « lJJ lJJ I-::< ·40

SNOW LOAD OBSERVATIONS ON ROOFS

Year:

Location:

1964-65

/ I)J

t

Poultry Bldg. (West Wing)

(Exposed, Insulated, Venti lated, Heatedl

ｾ

Poultry Bldg. (East Wing) . .

-I I

ｾ

__

Ｎ｟ｾ

...

ｾＧ［ｍＬｾｾＺＺＷＢｾＬＬＬ

"_ '3 "{' :'5 n-

Ib''':

20: i ,4 . • : '9 ,13 Il'\...J lA"'£52,' ( I A.-J / ; . . I'ZL' ! ro---';-- ...ＭＭＭＭＭｾ｟｟｟｟｟｟｟｟［ I I ! j I

ｾ

--l .

+ - - ,- - + - - - l I I

rh,

j

J ...ｾＭＭ <, i _ - -/ ａｖ＾ｾＭＭＭＭＢＬ '<, ｾ

o

o

11-20

---J_I

-1---1

! I

-l---.-/--

ＭＭｔＭＭＭＭＭＭｩＭＭｾ 20 '----

ｾＭ ｾＭＭＭ｟ｴＭＭＭＭ

-

I

II i i _ ＺＮ［［［［［［［ｾｾｾｾｾＺＺＺＺＺＺＺＺＺＺＺＺＺＬＺ＾Ｎｯ｣ＺＺＺ］ｾｾｾｾ 40

---POULTRY 8LDG (WEST WING)

MAXIMA AT #8 40 80 Cl <[ o -'

...

_....

u; ｾ

60'f---POULTRY BLDG. (EAST WING)

MAXIMA AT #5

NOVEMBER DECEMBER JANUARY FEBRUARY MARCH

U"> w :I: U Z Exposed, Insulated Attic Ventilated Attic not Heated Bldg. Heated

40ｲＭＭＭＭＭＭＭＭＫＭｾＭ

80

ｾＭｾＭＭＫＭＭＭＭＭＧＭＭＭＭＭｾ

-WIND DATA FOR, MONTREAL. QUE.

I

- -1

ｾＭＭＭＭｾＭＭＫＭＭＭＭｔＭ

i

.

-' 120 -' ｾ ｾ o z U"> Cl W .... <[ -' ::::> :::E ::::> u u <[ o 60 >--' u.. <[ • o a. Z :::E <[ w ｾ .... -40 SNOWFALL (DECEMBER - MARCH) NORMAL 1964-65 76·7" 50'6"

FIGURE II

SNOW LOAD OBSERVATIONS ON ROOFS

Year:

Location:

1964-65

STE. ANNE DE

BELLEVUE

I

QUE.

, __ｾ｟｟｟｟｟ＭｬＭＭＭＭＭＭ _ , - 25' :':. h - 25'ｾ ,,1 2' Parapet Exposed 41 Heated Insulated 8439 Berri 51. f IL."----"-_..L---'-"_L

All Roof Parts 11771 O'Brien Blvd. .L::JI 2

r

l 4" Parapet

L

3 0 '. " '" •

',-,'"'---'--=-.-1

ＭｴＮｾ L Iｾ _ ----ＭｾＭＭＭＭ

ｾｾＭＭＫＭＭｾＭＭＫ

I 1 ! ＭＭＭＭＭｾ｟｟｟ｲ｟ＭＭＭＭＭｾＭＭ 8 _ _ _ _ _ _ _ _ _ _- - - - 1 - __ "

,

\

,

\ \,....-'"', \ 12 \ 8439 8ERRI ST 11771 0'8RIEN BLVD 60 40 20 0 80 N I-u, ｾ 60 Cl <{ 0 -.J 40 20 0

(Exposed, Heated, Not In sulatedi

SNOWFALL (NOVEMBER -MARCH) NORMAL 1964·65 95· 0" 69'9"

FIGURE 12

Year:

Location:

1964-65

MONTREAL, QUE.

Pavilion Vachon

ＺｉＮｾ

.

ｾ Gymnasi um

Exposed, I nsulated, Heated, Non Ventilated

_L,,,-I.'_' '---- --'---'J ;.. / ' \ 1/ i ' ｉＭＭＭＭＭＭＭＭｲｾＭＭＭ｟｟｟ｬ 7 GYMNASIUM PAVILLON VACHON MAXIMA AT #2 60 40 20 0 80 ｾ I-u, jj;- ₆₀ Cl <[ 0 ...J 40 20 0

NOVEMBER DECEMBER JANUARY FEBRUARY MARCH

80 ---<f) UJ :I: u Z ...J 120 ...J ;;: ｾ o z (J) Cl UJ I-<[ ...J ::::> ｾ 40 u u <[ 0 60 Cl z _or ｾ a: 40 >- :::E ...J <[ 6 Cl UJ X UJ0- ₂₀ <[ (J) ::::; 0 50 >- 32 ...J u, <[ 0 Cl 0-Z ::::; 0 <[ _UJ UJ I-::::; -40

Exposed, I nsulater, Heated, Non Ventilated

SNOWFALL (DECEMBER - MARCH) NORMAL 1964-65 101'3" 113· 9"

FIGURE

13

SNOW LOAD OBSERVATIONS ON ROOFS

Year:

Location:

1964-65

80

60

40

..

t- ALCAN BUILDING NO. 60

U. #;- ₂₀ 0

-r

<t 0 -' 0

---

----7 l..--..--- ---- ...." Bldg. No. 60 Bldg. 62 1,'70 • 7 •'11 r 03 • & • /0 ｾＷ I}O A .2 100 ·5 • 9 .1 .+ , 120' f--- --- Z5}' (/)

....

:I: U ｾ

.:

120 -' <t U. ｾ 0 z (/) 80 0

....

t-<t -' :::> :::E ₄₀ :::> u u <t o 60 o Z :I: ｾ a.: 40 ｾ :::E ;;{ D-0 .... .... ｾ

e,

20 :::E -40

NOVEMBER DECEMBER JANUARY FEBRUARY MARCH

37:-

l

_L - L_ _

Section A-A

Exposed, Heated, Insulated

SNOWFALL (NOVEMBER -MARCH) NORMAL 1964-65 104'3" 72'1"

FIGURE

14

SNOW LOAD OBSERVATIONS ON ROOFS

Year:

Location:

1964-65

N G

Dalvay: Central Stores

(Sheltered from the North, Insulated, Unheated!

. 7 8 9 ｾ + 5 ｾ I 2 3

.

.

L ,,"-I

1-;3

I/':._L

I

,/4 I

'T-'

I 1 i ＮＭＭｾ r i . -I

DALAY: CENTRAL STORES

MAXIMA AT #6 40 60 - - , 20 0 80 N I-u, ｾ 60 0 <[ DALAY: RESIDENCE 0 ... 40 20 0 Dalvay: Residence 80 -en w :I: '-' Z ...- 120 ... <[ ｾ ｾ o z en o w I-<[ ... :::> ｾ 40 '-' u <[

o

60

NOVEMBER DECEMBER JANUARY FEBRUARY MARCH

.,. 1-I I I, 4 . I'". '. ｉＧｾ i«. 8.

l..l.

(Exposed, Heated, Insulatedl

o ｾ ｾ 40 ｾ ｾ <[ 0 o w w ｾ B; 20 ｾ o 50 >- 32 ... ｾ <[ 0 o CL z ｾ 0 <[ w W I-ｾ SNOWFALL (DECEMBER - MARCH) NORMAL 1964-65 89,5" 940"

METEOROLOGICAL DATA FOR:CHAR LOTTE TOWN, P EJ

FIGURE 15(a)

-40

SNOW LOAD OBSERVATIONS ON ROOFS

Year:

Location:

1964-65

P.E.I. NATIONAL PARK

I 140 ----_. ---I

L---120 I I

I Stanhope: Registration Office

I I I II I!

-2:--<$----I

+

L -100 -- - -

---1--

₃₉ I

--- -N 1 i

{I

... I u, , .1 _{4' 7·} ｾ i 80 .2 _5· g. 0 I eX . j ,;,. ｾＮ 0 _STANHOPE: -J REGISTRATION OFFICE 60 _... -I 73 I", " - - - -

---

ＭＭＭ｟Ｎ｟Ｍ｟Ｎ｟ＭｾＭＭ I ,'I

'L

I

T

40_1--- - - -

'

\

.

-I

l'

,

\ I ｾｊ \

,

I \ I I \\

,

ｾＭ

,

I I

,

\ I I

"

I (Sheltered from the East andｗ･ｳｾ Insulated,

20 --- ---I-- .-I I , I -! "J not Heated) ,,/"'" I I / i I

"-

i 0 ! I I , f - - - -

---t

I I I I i i

NOVEMBER

DECEMBER

JANUARY

FEBRUARY

MARCH

(J) w ::I: U ｾ ---i 120 ---J eX ｾ ｾ

-0 Z

ｾｲＫ

(J) 80 ｾＭＭ 0 w ... eX -J ::> :::E ₄₀ ::>. u u

Ｍｾ

eX 0 _{1--- - -} - -60 0 j.r ｾ :i 40 I ｾ a: ｾＭ j -" " II: WINO DIRECTION

,

ｾ

ｾＧ｜

ｾ

ｾｾ N _{: ｾ} <Xc W+E I

ｾ ｾｾ

Ａｾ ﾷＱＱｾ ｾＩ

IA

At,

ｾ

A

ＬＬｾ［ｉ｜

Oww 5 SNOWFALL ｾ fl; 20 1---:::E

I

VW'

VV

｜ｉｾ

ｾ ｾ

ｶｹｾ

VV

\ (DECEMBER-MARCH)NORMAL 1964-65 0 - - 89-5" 94-0" 50

Ｍｾ

_{ｐＱｲａｾ}

METEOROLOGICAL DATA FOR CHARLOTTETOWN, P. E.!.

ｾ 32ｾＭＭＭ

ｾ

- ｾ eX 0 0 Q. Z:::E ₀

FIGURE

15(b)

<[ w r ｾ ... -40

SNOW LOAD OBSERVATIONS ON ROOFS

Year:

Loco

tion.

1964-65

P.E.I. NATIONAL PARK

NS Tech College 20

ｉＭＭＭＭＭＭＭＭＬＭＭＭＭＭｾＭＭＫ｟｟｟

8/\ '

Ｍｾｾｾ

! o 60 N.R.C. LAB. _.', 14' Above Main Roof N.R. C. Lab. I 4 7_, , 24 ｾ h • 29.5'

(Exposed, Heated, I nsulated No Parapetl , 6/3 2 ! .L _" ,"\ I 7 ,..--'""'" I , ! r ',- j \i ---'A.

--i)l

ｾＭＭＭＭＭ 12

ｾＧＲ

12

?'h'

2 12 12 5 ｾＮｌｾＧ｜ｾ A ' ",'J \"". ｾ .. " - ｾＭＮＮＮｊｾ - - - - -I 8

.Je4.. _"....:::.:::- ...

I ENGINEERING BLDG. 10 201---o 60

L.

T

---+---+:"--:;t--''<--f---I

J.

I 12 __ Ｍｾｾ｟ 12

C::

40 -Cl « o -'

..

I-u,

ｾ｟｟ａ｟ｴ｟ＭＭＭＭＭＧｾｾｾｾＴｾｾｾｾｾｾｾｾｕ

NOVEMBER DECEMBER

JANUARY

FEBRUARY

MARCH

(J) LU ox: U Z o ! I I I ../ I 1 I i ! I I I I -Engineering Bldg.

e·'

12" -r,:' • ,/4 J__ I

,

N

/f-I! 'J-H . . . T r - ,ＴｾＧ ＭＵＧＢＢＧﾷＭＯ］ｾｾＮＧＭＱ ｾ I ,i I } . /

H..--4°' 2' <9', _ L ' I b

7.f--/50 - - - - v

(Sheltered, Not I nsulated, Heated)

FIGURE

16

SNOWFALL (NOVEMBER - MARCH) NORMAL 1964·65 56·4" 84""

J

-,

1 I 60 -40

ｩＨＬｦｲｾｾｾｾｦｻ

_ｾ

_e;

ａｩＡｨｾｾｨｲ

ｾｴｾｾ

20

\fJ'

ｾｾ

VI

'VW'

V

un

1

V VW

i

V

ｾｹ

ｾ

o

I I

ｉＭｾＭｾＭＭＭＭｃｾ｣ＧＺＺＭｴＭｾＭＭＭＧ｟Ｍｉ

_ _

ｾｾ

ｾ ｾ

!I ｾ I

SNOW LOAD OBSERVATIONS ON RO OFS

Year:

Location:

1964-65

8UILDING 64

ｍ･｣ｾ Equip.Room Bldg.64

I Exposed, Heated. Insulated)

ｨＧｾ /2

"

"

_\

Ｎ｟ｾＬＭＭＭＭＭＭＭＭＱ

!

MECH. EQUIP ROOM

, '-60 40 20 0 80 >-u, ₆₀ 1i: 0 <[ :3 40 20 0 NOVEMBER DECEMBER ｾ 200 ｾ :I: u Z -" 160 -" <[ ｾ 0 ｾ 120 0 ｾ >-<[ -" ::>

'"

80 ::> u u <[ 40 0 -60

"

0 "" :i 40 3' C>. ｾ

_'"

ｾ ci ｾ x ｾ <[ e;20

'"

0 50 ｾ 32 ;:; ;c z C>. ₀

'"

<[ ｾ ｾ >-'" _-40

JANUARY MARCH APRIL

{Nnt Sheltered Except from East,not Heated, l nsulatedi

SNOWFALL (NOVEMBER- APRIL) NORMAL 1964-65 118'0" 238'8"

FIGURE 17

SNOW LOAD OBSERVATIONS ON ROOFS Year:

Location:

1964-65

40 ＭＭＭＭｾＭＭＭＭＧＭＭＭＭＭＭＮＭ 20ｉＭＭＭＭＭＭｾＭＮＢ " ｾＭＭＭＭＭＭＭＭＫＭＭＭＭＭｴ )0 1(,0

ｾ

Ｇ

';

----.---/0 /1 /2 ,'3

Ｏｾｴﾷ

"i/o

--i'i

I ' __J , ｾＧＡ｟Ｚ｟＿ＵＺＵ

ｾ

C::::,.r--I :' ; 4 c' (, 7 13 ? Arch Hanger 4'2'1 j - - .ＭＭｾＭＭＭｩｵ

ｾ

ＢＧ • 10 • Ie, .2/

-I

7 ;'B i . } .11 .17. 27 ｾ 29 I

__ fJ·4

3

0_• U 303 ... -Z- • , •I:' • /8 • 2; . } ! I ...,.(;; • 5'2 • 714•rJ .19 •74 • 33 1 .

［ｾＵｾＧＷ

ｾ

Ｍ Ｇｾ ｟ｾ 53 .1 V].51f FrontView -- • Canti leverHangar -\I T.I ＮＴＷＮｾＯＮ［ ..J. I ｾ

>---'-

;1

i" /I"2«/ ＱＳｾＯ .7 .5 10. I 11=705

0'

I I} 1j i i • ｉｉＮｾ .1 ." •G 12. , 1..--/3 7ｾＭ -1--60 '.-i ME Garage -ＭＭＭＭｾＭＭ

MARCH

r:

---

---JANUARY

FEBRUARY

)

CANTILEVER HANGARA

ＭＭＭ［［ｾ［ｻｾ

｜ＬｾＭ

3 4

ＲＰｾ

\ M.E. GARAGE

NOVEMBER

DECEMBER

80 o 60 40

--' 120---'

""

lL ｾ o z (/) (/) w :r u z Cl

""

o -'

o

-60 " ,---- -

-L

'

I i oI - - - ' - ' f - - - _ _+ _ _ - - - + - - - 1 60 D W

I-""

-' :::> ｾ 40 -u u

""

Cl ｾ ｾ 40ｉＭＭＭＭＭＭＭＭＫｾＭＭＭＭＭＫＭ｟ＺＺ］ＺＺ｟］］ｾＭＭＭＭＫ｟｟ＭｾＭＭＭＭ ｾ ｾ ""0 Cl W W X D..

""

(/) ｾ -40 _. _. _. -SNOWFALL (NOVEMBER-FEBRUARY) NORMAL 1964·65 36-4" 102-3"

FIGURE

18

SNOW LOAD OBSERVATIONS ON ROOFS

Year:

Location:

1964-65

R.C.A.F. COMOX,

B.C.