Flat roof repair in St. Catharines

Flat roof services in St. Catharines

Much of St. Catharines's housing is older, and older houses often have flat roofs over rear additions, porches and garages. Typical signs are a stain on the kitchen ceiling, water at a skylight or a roof with several worn layers. Its design snow load is among the lightest of the cities on this site, so freeze–thaw and summer storms do more damage than snow weight. We find where the water gets in, fix that spot and tell you how much life the rest of the roof has.

When a roof is past repair, we replace it with EPDM, TPO, PVC or modified bitumen, and fix the drainage so water does not sit on the new membrane. Owners and property managers also book inspections and maintenance visits.

Canal city: St. Catharines from Port Dalhousie to Western Hill

St. Catharines grew around the first Welland Canal, built from 1824 to 1833, which made it a commercial and industrial hub for the Niagara Peninsula. It became a city in 1876. Postwar growth was explosive: population rose from 37,984 in 1951 to 84,472 in 1961, and the city annexed Grantham Township, Merritton and Port Dalhousie. General Motors of Canada was long its largest employer. Census data show about 71% of homes were built before 1981 and 33% before 1961.

Downtown, Port Dalhousie, Merritton and the North End have older brick buildings and houses where flat roofs over rear additions and storefronts are common. The western neighbourhoods such as Western Hill and Glenridge, and annexed Grantham, reflect the postwar expansion, when schools, apartment blocks and plazas with low-slope roofs were built. The Pen Centre is a large regional shopping centre, and the city has about 140 industrial buildings, including the former GM plant lands. With so much older housing and so few homes built since 2001 (about 10%), roofs of an older vintage are a large part of the city.

St. Catharines weather and your flat roof

Ontario's Building Code sets the climate values used to design roofs in each municipality. They show what a flat roof in St. Catharines has to handle.

• 1 kPaGround snow load (about 21 lb per sq ft)
• 0.4 kPaRain load added to snow (Sr)
• 23 mmRain in a 15-minute storm (design value)
• 92 mmRain in one day, 1-in-50-year storm
• -16 °CJanuary design temperature
• 3,540Heating degree-days per year
• 0.46 kPaHourly wind pressure, 1-in-50-year

Snow loads are close to the Toronto figure. Freeze–thaw cycles through the winter are what open tired seams and flashings.

Short summer storms can still drop 23 mm of rain in 15 minutes, so drains and scuppers have to be clear and sealed.

Environment and Climate Change Canada climate normals (1991–2020) record about 137 cm of snowfall a year at the St. Catharines Airport station.

Source: Ontario Building Code, Supplementary Standard SB-1, Table 1.2

Homes and buildings in St. Catharines

The age and type of buildings shape the flat roofs we see. These are the 2021 Census figures for St. Catharines.

• 71%Homes built before 1981
• 10%Homes built since 2001
• 61%Detached and semi-detached houses
• 9%Row houses and townhouses
• 11%Apartments in buildings of 5+ storeys
• 36%Households that rent

About 71% of homes in St. Catharines were built before 1981, more than in 36 of the 40 Ontario cities on this site. Older houses often have flat roofs over rear additions, kitchens and porches, sometimes with two or three layers of old roofing on top of each other. Replacing one usually starts with a full tear-off and a look at the wood deck underneath.

36% of households in St. Catharines rent. Landlords and property managers can send photos and the tenant's description of the leak, and we reply with the scope and a quote by email. See apartment buildings.

Source: Statistics Canada, 2021 Census Profile

St. Catharines: facts for property owners

• Population of St. Catharines: 136,803 (2021 Census). Source
• St. Catharines is part of the Regional Municipality of Niagara.
• Flood Alleviation Program (FLAP): Rebate up to 90% of eligible costs, max $5,000, for single/semi-detached homes built before 2012 (backwater valves, weeping tile disconnection to sump pump). Source

Rules and programs change. Confirm current details with the municipality before you start work.

Starting prices in St. Catharines

Starting prices in CAD before 13% HST, based on typical Ontario contractor rates (mostly Toronto and the GTA). The final price depends on roof size, access, the layers to remove, the membrane, drains and flashings, and is confirmed in your written quote.

See all prices.