A lumbered slope framed over a flat roof deck to move water toward the drains, with a two-ply system installed over it.
Lumbered Slope Build and Two-Ply System, Toronto
Open Lumbered Slope Build and Two-Ply System, Toronto
Flat roofing in Ajax, Durham Region
Ajax Flat Roof Repair, Installation, and Replacement
We repair, replace and install flat roofs across Ajax in Durham Region. Free no-obligation quotes, warrantied workmanship and 24/7 emergency response.
What you get from Flat Roofs Toronto
24/7 Emergency Response
Leaks do not wait for business hours.
Free No-Obligation Quotes
Scope, system and number, in writing, first.
Manufacturer & Workmanship Warranties
The materials and the installation are both covered.
Flat Roofs Only
Low-slope work is the whole business, not a sideline.
Flat Roofs in Ajax, Up Close
Most of Ajax was built subdivision by subdivision, which shapes the residential side of our work. Houses are pitched, but there is nearly always a flat deck somewhere: over the garage, above a portico, or on a rear addition or sunroom. Those decks are small, tied into shingles or a brick wall on at least one side, and they leak at that junction long before the membrane itself gives out. Commercially, the business parks and retail centres run wide low slope fields with rooftop units, and properties toward the Lake Ontario shoreline take steady wind with nothing in front of them to slow it down.
What We Do on Ajax Roofs
In Ajax we handle leak tracing and repair on garage and addition decks, flashing and transition rebuilds where flat meets shingle, tear off and replacement, drain and scupper work on commercial fields, skylight reflashing, and 24/7 emergency flat roof repair. Residential and commercial, with free no-obligation quotes.
Where Ajax Sits in Our Service Area
The plan opens on this part of the GTA. Every city we cover in the region is in the legend beside it.
Select a region on the plan
Systems That Suit Ajax
For the small decks that dominate Ajax housing, self adhered two ply modified bitumen or EPDM gives a clean wall termination and handles the shingle transition well. Business park and retail fields are better suited to mechanically fastened TPO, with tightened perimeter fastening for shoreline wind. Compare every flat roofing system.
Two Ply
Modified Bitumen
Torch-applied or self-adhered SBS in two plies, with a granule-surfaced cap. The default on Toronto houses because it handles tight perimeters, curbs and wall terminations without a wide sheet.
- 15 to 20 year service life
- Redundant second ply
- Repairs patch cleanly
Torch Free
Cold-Ply
The same two-ply build assembled in cold adhesive rather than with an open flame. It is what we specify over occupied buildings, beside vinyl siding and anywhere a torch is not welcome.
- No open flame on the roof
- Low odour on occupied buildings
- Granule-surfaced cap
Single Ply
TPO and PVC
Hot-air welded thermoplastic sheet, laid in wide rolls with far fewer seams. It suits large commercial fields, and the reflective white surface keeps a warehouse roof cooler through a Toronto summer.
- Welded rather than glued seams
- Reflective white surface
- Fast over large areas
Rubber
EPDM
A synthetic rubber membrane that stays flexible through freeze thaw movement and takes ponding better than most. Common on garages, additions and small commercial decks.
- Flexible in cold weather
- Tolerates standing water
- Simple to detail and repair
Local Considerations in Ajax
The conditions that decide how long a roof here lasts, and what we detail differently because of them.
- Snow slides off the main pitched roof onto the lower garage or addition deck, piles up, melts unevenly and dams right at the transition, which is where most residential leaks begin.
- Sites closer to the lake get sustained wind with little shelter, so perimeter fastening and edge metal on commercial fields deserve a look every spring.
- Freeze thaw cycling opens laps and stresses sealant at penetrations, and damage done during a February thaw usually surfaces as an April ceiling stain.
Recent Flat Roofing Projects
Real jobs photographed on site by the crews who did them.
Flat Roof Application Detail, Toronto
A detail from a flat roof membrane application, showing the finished surface of the system.
Attic Inspection and Blown-In Insulation, Toronto
Inspection of a flat roof attic space followed by blown-in insulation. The cavity is checked before any insulation is added.
Flat Roofing Advice
What we have written about keeping a low-slope roof watertight in this climate.
Flat Roofing in Ajax: Systems and Costs
Flat roofing in Ajax: compare membrane systems, 2026 costs per square foot, code and drainage rules, and how to judge a low-slope roofing quote.
Flat Roof Repair in Ajax: Costs and Common Problems
Flat roof repair in Ajax: 2026 cost ranges, the most common low-slope roof failures, permit rules, and how to decide between repairing and replacing it.
Flat Roofing in Durham Region: Ajax, Pickering, Whitby and Oshawa Guide
A practical 2026 guide to flat roofing in Durham Region: membrane options, installed costs, permits, common failures and how to choose a contractor.
Ajax Flat Roofing Questions
Straight answers to what people ask us about a roof on this street.
Why does my Ajax garage roof leak only after a snowmelt?
Because the water is not coming through the field, it is getting in at the transition. Snow sliding off the pitched roof loads the lower deck, ice forms at the wall or the shingle junction, and meltwater backs up above the flashing. In Ajax that detail is the first thing we check. Rebuilding the flashing with a proper upturn and counterflashing usually ends it.
How long does a flat roof replacement take on an Ajax home?
A garage or addition deck is typically a one day job: tear off, deck inspection, insulation where the assembly calls for it, membrane, edge metal and flashings, all closed in before we leave. Larger Ajax residential sections, or anything needing deck repair, can run two days. We never open more roof than we can make watertight the same day.
Do you work on Ajax business park and plaza roofs?
Yes. Commercial flat roofing in Ajax is a large part of what we do: leak investigation across a big field, seam and flashing repair, drain and sump rebuilds, curb flashings around rooftop units, walkway pads along service routes, and full tear off and replacement. Work can be phased and scheduled off hours so tenants stay open throughout.
Is a flat roof repair in Ajax worth it, or should I replace?
If the leak is local, the membrane elsewhere is still flexible and the insulation is dry, repair is the sensible call and buys real time. Replacement makes sense once we find wet insulation over a wide area, several failed seams, or a second aged layer. On an Ajax roof we cut a small test opening to check the assembly before recommending either.
Nearby Areas We Also Cover
Flat roofing in the streets either side of Ajax:
Pickering • Whitby • Oshawa • All of Durham Region
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Reviews From Across the GTA
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Get a Free Flat Roof Quote in Ajax
Free, no-obligation quotes across Ajax and the rest of Durham Region, and a 24/7 emergency line on (647) 333-3528.