Flat roof repair in Windsor

Flat roof services in Windsor

Much of Windsor'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.

Walkerville, Ford City and the auto belt in Windsor

Windsor reached 104,415 people by 1941 as the auto industry grew, and it annexed Sandwich, Ford City and Walkerville in 1935, then Ojibway and Riverside in 1966. Its economy still rests on manufacturing, with a Stellantis assembly plant, Ford engine plants and many tool-and-die and parts makers. Census data shows about 68% of homes were built before 1981, and about 39% before 1961.

Much of Windsor is therefore mid-century housing, and older areas such as Ford City and Walkerville often have brick homes with flat roofs over additions and garages. Downtown, Ouellette Avenue and the old Sandwich district have commercial and institutional buildings, many with flat roofs behind parapets. The auto plants and parts suppliers occupy large low-slope buildings, and a plant that has been renovated over the decades often has roof sections of different ages.

Windsor 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 Windsor has to handle.

• 0.8 kPaGround snow load (about 17 lb per sq ft)
• 0.4 kPaRain load added to snow (Sr)
• 28 mmRain in a 15-minute storm (design value)
• 103 mmRain in one day, 1-in-50-year storm
• -16 °CJanuary design temperature
• 3,400Heating degree-days per year
• 0.47 kPaHourly wind pressure, 1-in-50-year

Snow loads here are a little lower than in Toronto, but freeze–thaw cycles still work water into open seams and cracked flashings through the winter.

A design storm can drop 28 mm of rain in 15 minutes. On a flat roof that water has to reach a drain or scupper quickly, so clear drains and sound drain flashings matter as much as the membrane.

Environment and Climate Change Canada climate normals (1991–2020) record about 140 cm of snowfall a year at the Windsor A station.

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

Homes and buildings in Windsor

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

• 68%Homes built before 1981
• 14%Homes built since 2001
• 65%Detached and semi-detached houses
• 7%Row houses and townhouses
• 13%Apartments in buildings of 5+ storeys
• 37%Households that rent

About 68% of homes in Windsor were built before 1981, more than in 33 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.

37% of households in Windsor 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

Storms that hit Windsor

• 24 August 2016: An F1 and an F2 tornado touched down in the evening, damaging parts of Windsor and LaSalle. Source
• August 2017: A late-August storm dropped 285 mm of rain in 32 hours on Windsor, a flash-flooding event listed among Environment Canada's top weather events of 2017. Source

Storms like these are when blocked drains, loose flashings and open seams show up. After a big storm, check the ceilings under the roof and send us photos of any new stain.

Windsor: facts for property owners

• Population of Windsor: 229,660 (2021 Census). Source
• City lists 'Asphalt roof shingling (non-structural)' as not needing a permit. Source
• Stormwater financing (since 2025): Stormwater fee based on each property's impervious area; incentives listed include free tree subsidy, rain barrel rebate, stormwater credit program and appeals. Source
• Mandatory downspout disconnection: After recent flooding the City is implementing a mandatory downspout disconnection policy, exemptions case by case; free disconnection service. Source

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

Starting prices in Windsor

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.