Hamilton Flat Roof Repair finds and fixes flat roof leaks for homeowners, landlords and property managers across Hamilton. We repair EPDM, TPO, SBS torch-on and tar and gravel membranes, replace wet insulation, and rebuild drains, scuppers and parapet flashings. We are one of the few flat roofing companies in Hamilton that publishes what the work actually costs.
Serving Hamilton and surrounding areas
Hamilton has an unusual concentration of flat roofs for a city this size, and most of them are older than the people living under them. The brick commercial blocks along Barton, King and James, the north end industrial stock, and the flat-roofed rear additions on half the century houses below the escarpment were all built with parapets and internal drains rather than eaves and gutters. That detail matters, because a flat roof with a parapet has nowhere to shed water except through a drain. When the drain blocks, the roof becomes a shallow pond with a wall around it.
Three things account for most of what we are called to. Ponding. A flat roof is not actually flat. It is built with roughly 2 percent fall toward its drains or scuppers, and decks that settled, or that were framed level in the first place, hold water instead of shedding it. Water still standing 48 hours after rain counts as ponding, and it is not harmless weight: ponded water adds about 5.2 pounds per square foot for every inch of depth. Two inches across a small roof is several tonnes the deck was never designed to carry, and it sits exactly where the membrane is weakest. Freeze-thaw at the seam. Hamilton's winters cross the freezing point constantly rather than staying cold, so ponded water freezes and thaws repeatedly in the same spot. Every cycle works at the seam and the flashing. Movement at the edges. Parapets, curbs and drains are where two materials meet and move against each other. Almost no leak we find starts in the open field of the membrane. It starts at an edge.
The membrane is the cheap part. The insulation underneath it is what decides the bill. Once water gets through the membrane it does not stay put. It travels sideways between the membrane and the insulation, so the wet area is almost always far larger than the hole and rarely directly above the stain on the ceiling. Wet insulation does not dry out in place under a sealed membrane, it loses most of its R-value, and it stays a permanent water reservoir feeding the deck below. This is why we cut a test core before quoting anything. It is the only way to know whether you are buying a patch or a section, and any quote issued without one is a guess. It also tells us how many roofs are already up there. Older Hamilton buildings frequently carry two or three layers, and once a deck is loaded with that much accumulated roofing, another overlay is usually the wrong answer structurally as well as financially.
EPDM is the black rubber membrane on most residential flat roofs here. It fails at the seams and at the flashings rather than in the field, and it is repaired with cleaned, primed seam tape rather than with caulk. Caulk on an EPDM seam is a two-month repair.
TPO is the white or light grey membrane common on newer builds and additions. Its seams are hot-air welded, not taped, so a proper TPO repair needs a welder and a technician who can set the temperature and speed to the sheet. A welded seam is tested with a probe afterwards.
SBS modified bitumen is the two-ply torch-applied system found on a great many Hamilton flat roofs. Repairs rebuild both plies, base and cap, staggered so the laps do not stack. Torch work carries a fire watch, and it is not appropriate over every deck or near every wall assembly.
Built-up roofing is the oldest system still in service here, layers of felt and bitumen under gravel ballast. Repairs mean sweeping back the gravel, cutting out the failed area and rebuilding to the same ply count. It is unglamorous and it works.
The repair is the easy half. Finding the entry point is the job, and it is what separates a repair that holds from one that moves the stain to a different part of the ceiling.
Drains, scuppers and parapet flashings are where most Hamilton flat roofs actually fail. A drain that has lost its clamping ring, or a parapet cap that has opened at a joint, will leak regardless of how sound the membrane is.
We take emergency calls for active leaks, storm damage and blocked drains during heavy rain. We will stop the water first and quote the permanent repair afterwards.
We repair and maintain flat roofs on commercial, industrial and multi-residential buildings across Hamilton. Commercial roofs fail differently from residential ones, because there is equipment on them and people walking around it.
Every rooftop unit sits on a curb, and every curb is a penetration through the membrane. Units that have been serviced repeatedly are usually surrounded by damaged membrane, because technicians work where they can stand.
Twice-yearly inspection in spring and autumn, with drains cleared, seams probed and a written condition report with photographs. On a portfolio of buildings this converts unpredictable emergency spend into a planned line item.
Call us if you recognise any of the following.
Every job follows the same five steps.
Our rule is about wet area, not about age. We repair when the wet insulation is confined to roughly a quarter of the roof or less and the deck is sound. We replace when it is more than that, when there are already two or more layers up there, or when the deck itself has been compromised. A roof with three isolated leaks and dry insulation is a repair, even at twenty years old. A ten-year-old roof with half its insulation saturated is a replacement, because you would be paying to rebuild most of it anyway and tying new work into failing material. We tell you which side of that line you are on, in writing, with the core samples to show why.
No competitor on page one of this search publishes a number. These are typical Hamilton ranges, not quotes.
| Job | Typical range |
|---|---|
| Leak investigation with core cut | $350 to $700 |
| Seam or flashing repair | $500 to $1,500 |
| Sectional repair including wet insulation replacement | $1,800 to $4,500 |
| Roof drain rebuilt or replaced | $700 to $2,000 |
| Scupper or parapet flashing rebuilt | $900 to $3,000 |
| Emergency call-out and temporary dry-in | $450 to $1,200 |
| Full replacement, per square foot | $10 to $20 |
| Twice-yearly inspection contract | Priced per building |
Four things move these numbers: how much insulation is wet, how many layers are already on the deck, access for material and equipment, and whether the work is scheduled or an emergency.
We work across Hamilton and the surrounding communities.
Flat roof leaking? We find the entry point, show you the core, and quote a fixed price. Serving Hamilton, Stoney Creek, Dundas, Ancaster and Waterdown.
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