Roof Snow Load by Canadian City

Canada

Look up the ground snow load for your city and get the roof and deck design loads for a house, straight from the National Building Code of Canada 2020.

Your city

1. Location

Values are for the location named in NBC 2020 Table C-2. Do not interpolate for other places; ask your building department.

Result

0

From NBC 2020

Roof load uses NBC 2020 Part 9, 9.4.2.2: S = Cb × Ss + Sr, never less than 1 kPa. Decks use the greater of that and 1.9 kPa (9.4.2.3).

Where these numbers come from

Every Ss and Sr value is copied from the National Building Code of Canada 2020 (second printing, with the March 2025 errata), Division B, Appendix C, Table C-2. Ss is the 1-in-50-year ground snow load and Sr the associated 1-in-50-year rain load, both in kPa. Nothing here is estimated or interpolated.

  • Roof load (Part 9) = 0.55 × Ss + Sr, minimum 1 kPa (NBC 2020, 9.4.2.2)
  • Deck load = the greater of the roof load and 1.9 kPa (NBC 2020, 9.4.2.3)
  • psf = kPa × 20.885

NBC 2020 itself warns that Ss values carry an uncertainty of about 20% and should not be interpolated for unlisted places. Your province's adopted code and your building department govern; NBC 2025 has updated climate data.

Snow loads by province and city

Ss and Sr from Table C-2. Roof load is the Part 9 value for a roof wider than 4.3 m.

British Columbia

City Ss kPa Sr kPa Roof kPa Roof psf
Vancouver 1.8 0.2 1.19 24.9
Burnaby 2.9 0.7 2.3 47.9
Surrey 2.4 0.3 1.62 33.8
Richmond 1.5 0.2 1.03 21.4
North Vancouver 3 0.3 1.95 40.7
Abbotsford 2 0.3 1.4 29.2
Chilliwack 2.2 0.3 1.51 31.5
Victoria 1.1 0.2 1 20.9
Nanaimo 2.1 0.4 1.56 32.5
Kelowna 1.7 0.1 1.04 21.6
Kamloops 1.8 0.2 1.19 24.9
Penticton 1.3 0.1 1 20.9
Prince George 3.4 0.2 2.07 43.2
Prince Rupert 1.9 0.4 1.44 30.2
Fort St. John 2.8 0.1 1.64 34.3
Dawson Creek 2.5 0.2 1.58 32.9
Cranbrook 3 0.2 1.85 38.6
Nelson 4.2 0.1 2.41 50.3

Alberta

City Ss kPa Sr kPa Roof kPa Roof psf
Calgary 1.1 0.1 1 20.9
Edmonton 1.7 0.1 1.04 21.6
Red Deer 1.8 0.1 1.09 22.8
Lethbridge 1.2 0.1 1 20.9
Medicine Hat 1.1 0.1 1 20.9
Fort McMurray 1.5 0.1 1 20.9
Grande Prairie 2.2 0.1 1.31 27.4
Banff 3.3 0.1 1.92 40

Saskatchewan

City Ss kPa Sr kPa Roof kPa Roof psf
Saskatoon 1.7 0.1 1.04 21.6
Regina 1.4 0.1 1 20.9
Prince Albert 1.9 0.1 1.15 23.9
Moose Jaw 1.4 0.1 1 20.9
Swift Current 1.4 0.1 1 20.9
Yorkton 1.9 0.1 1.15 23.9
North Battleford 1.7 0.1 1.04 21.6

Manitoba

City Ss kPa Sr kPa Roof kPa Roof psf
Winnipeg 1.9 0.2 1.24 26
Brandon 2.1 0.2 1.36 28.3
Steinbach 2 0.2 1.3 27.2
Portage la Prairie 2.1 0.2 1.36 28.3
Thompson 2.4 0.2 1.52 31.7

Ontario

City Ss kPa Sr kPa Roof kPa Roof psf
Toronto 0.9 0.4 1 20.9
Mississauga 1.1 0.4 1.01 21
Brampton 1.3 0.4 1.12 23.3
Oshawa 1.4 0.4 1.17 24.4
Hamilton 1.1 0.4 1.01 21
St. Catharines 1 0.4 1 20.9
Niagara Falls 1.8 0.4 1.39 29
Ottawa 2.4 0.4 1.72 35.9
Kitchener 2 0.4 1.5 31.3
Waterloo 2 0.4 1.5 31.3
Cambridge 1.6 0.4 1.28 26.7
Guelph 1.9 0.4 1.44 30.2
London 1.9 0.4 1.44 30.2
Woodstock 1.9 0.4 1.44 30.2
Windsor 0.8 0.4 1 20.9
Sarnia 1.1 0.4 1.01 21
Barrie 2.5 0.4 1.78 37.1
Orillia 2.4 0.4 1.72 35.9
Owen Sound 2.8 0.4 1.94 40.5
Peterborough 2 0.4 1.5 31.3
Kingston 2.1 0.4 1.56 32.5
Belleville 1.7 0.4 1.34 27.9
Cornwall 2.2 0.4 1.61 33.6
North Bay 2.2 0.4 1.61 33.6
Sudbury 2.5 0.4 1.78 37.1
Sault Ste. Marie 3.1 0.4 2.11 44
Timmins 3.1 0.3 2.01 41.9
Thunder Bay 2.9 0.4 2 41.7
Kenora 2.5 0.3 1.68 35

Quebec

City Ss kPa Sr kPa Roof kPa Roof psf
Montreal 2.6 0.4 1.83 38.2
Laval 2.6 0.4 1.83 38.2
Quebec City 3.6 0.6 2.58 53.9
Lévis 3.3 0.6 2.42 50.4
Gatineau 2.5 0.4 1.78 37.1
Sherbrooke 2.2 0.6 1.81 37.8
Saguenay 2.7 0.4 1.89 39.4
Trois-Rivières 2.8 0.4 1.94 40.5
Drummondville 2.5 0.4 1.78 37.1
Granby 2.3 0.4 1.67 34.8
Saint-Jérôme 2.7 0.4 1.89 39.4
Rimouski 3.8 0.4 2.49 52

New Brunswick

City Ss kPa Sr kPa Roof kPa Roof psf
Moncton 3 0.6 2.25 47
Fredericton 3.1 0.6 2.31 48.1
Saint John 2.3 0.6 1.86 39
Bathurst 4.1 0.6 2.86 59.6
Edmundston 3.4 0.6 2.47 51.6

Nova Scotia

City Ss kPa Sr kPa Roof kPa Roof psf
Halifax 1.9 0.6 1.65 34.4
Dartmouth 1.6 0.6 1.48 30.9
Sydney 2.3 0.6 1.86 39
Truro 2 0.6 1.7 35.5
Kentville 2.6 0.6 2.03 42.4
Yarmouth 1.8 0.6 1.59 33.2

Prince Edward Island

City Ss kPa Sr kPa Roof kPa Roof psf
Charlottetown 2.7 0.6 2.09 43.5
Summerside 3.1 0.6 2.31 48.1

Newfoundland and Labrador

City Ss kPa Sr kPa Roof kPa Roof psf
St. John's 2.9 0.7 2.3 47.9
Corner Brook 3.7 0.6 2.64 55
Gander 3.7 0.6 2.64 55
Stephenville 4.1 0.6 2.86 59.6
Happy Valley-Goose Bay 5.3 0.4 3.32 69.2
Labrador City 4.8 0.3 2.94 61.4

Yukon

City Ss kPa Sr kPa Roof kPa Roof psf
Whitehorse 2 0.1 1.2 25.1
Dawson 2.9 0.1 1.7 35.4

Northwest Territories

City Ss kPa Sr kPa Roof kPa Roof psf
Yellowknife 2.2 0.1 1.31 27.4
Hay River 2.4 0.1 1.42 29.7
Inuvik 3.1 0.1 1.81 37.7

Nunavut

City Ss kPa Sr kPa Roof kPa Roof psf
Iqaluit 2.9 0.2 1.8 37.5
Rankin Inlet 3 0.2 1.85 38.6

Ontario: SB-1 and Hamilton

Ontario designs use Supplementary Standard SB-1 of the 2024 Building Code rather than NBC Appendix C. Its values match the table above for every Ontario city listed, except Hamilton, which SB-1 splits into four zones:

Hamilton snow loads, OBC 2024 SB-1 Table 2
Zone Ss kPa Sr kPa
Above Escarpment - West of John C. Munro Int'l Airport 1.5 0.4
Above Escarpment - East of John C. Munro Int'l Airport 1.3 0.4
Below Escarpment - West of Highway 403 1.1 0.4
Below Escarpment - East of Highway 403 1.1 0.4

Common questions

What is the snow load in Toronto?
NBC 2020 Table C-2 gives Toronto (City Hall) a ground snow load Ss of 0.9 kPa and rain load Sr of 0.4 kPa. For a typical house roof under Part 9 that is 1 kPa (20.9 psf). North York and Scarborough are listed higher, at 1.2 kPa ground snow.
What is the snow load in Ottawa?
Ss 2.4 kPa, Sr 0.4 kPa (Ottawa City Hall), so a Part 9 house roof load of 1.72 kPa (35.9 psf).
What is the snow load in Calgary and Edmonton?
Calgary: Ss 1.1 kPa, Sr 0.1 kPa, roof 1 kPa. Edmonton: Ss 1.7 kPa, Sr 0.1 kPa, roof 1.04 kPa. Alberta uses the NBC 2023 Alberta Edition, which is based on NBC 2020.
What is the snow load in Montreal?
Ss 2.6 kPa, Sr 0.4 kPa (Montreal City Hall), so 1.83 kPa (38.2 psf) on a typical house roof. Quebec City is much higher: Ss 3.6 kPa, roof 2.58 kPa.
What is the snow load in Vancouver?
Vancouver City Hall: Ss 1.8 kPa, Sr 0.2 kPa, so a roof load of 1.19 kPa. It varies a lot across Metro Vancouver, from 1.5 kPa in Richmond to 3.0 kPa in North Vancouver.
How do you calculate roof snow load for a house in Canada?
For houses and small buildings, NBC 2020 Article 9.4.2.2 uses S = Cb × Ss + Sr, with Cb = 0.55 (0.45 where the entire roof width is 4.3 m or less), and never less than 1 kPa. Larger buildings use the full Part 4 formula, S = Is [Ss (Cb Cw Cs Ca) + Sr].
What snow load does a deck need to carry?
NBC 2020 Article 9.4.2.3 says a deck serving one dwelling must carry the specified roof snow load or 1.9 kPa, whichever is greater. In Winnipeg the roof load is 1.24 kPa, so 1.9 kPa governs; in Quebec City it is 2.58 kPa, so the deck must carry that.
How do I convert kPa to psf?
Multiply by about 20.89 (1 kPa = 20.885 psf). So 1.0 kPa is 20.9 psf and 2.0 kPa is 41.8 psf.