Torch-On Roofing in Abbotsford, BC
Torch-on belongs to the modified-bitumen family, and what sets it apart is not the material so much as how it gets onto the roof. The membrane arrives in rolls, but it does not stay a set of separate rolls. Heat is used to bond the membrane to the prepared surface and to form the laps between adjoining sheets, and much of what matters about a torch-on roof — how it performs, what can be repaired, what it costs to put right — follows from that.
What it is
Torch-on is a flat-roof system made from modified bitumen. It uses membrane sheets that are heat-applied to a prepared roof surface: a propane torch heats the underside of the sheet so that it bonds directly to what is beneath it.
That heat-applied bond is the defining characteristic. Other low-slope systems attach differently, and the difference shows up later in how the roof behaves and how it is worked on. If you are weighing torch-on against the alternatives rather than dealing with one you already have, low-slope roof systems covers the wider comparison.
How separate sheets become one roof
The bond is only as good as what it bonds to, which is why preparation carries weight on this system. GoodVans Roofing cleans and primes the surface before the membrane goes down, and priming exists precisely to give the heated bitumen something to grip.
The laps are where adjoining sheets meet, and forming them correctly is an important part of the installation. GoodVans Roofing heats and bonds each section in turn, then checks every seam and tests the roof for leaks before the job closes out.
That is the awkward thing about assessing a torch-on roof after the fact. Once the roof is complete, appearance alone does not tell you how well every lap or detail was formed during installation.
Where the membrane stops being the whole question
A torch-on roof is not only its field area. Every drain, vent, curb and piece of rooftop equipment interrupts the membrane, and each of those interruptions has to be terminated and integrated into the same continuous surface.
Those points behave differently from the open field. Their condition can differ from it because they involve additional transitions and detailing, and a membrane in reasonable order across the field can sit alongside terminations that are not.
Drainage matters here too, though for reasons that belong to the roof rather than to the system: persistent ponding can place additional demand on the membrane, laps and details.
Looking at an existing torch-on roof
When something is going wrong, a few questions shape what follows.
Whether the problem is confined to one area, or showing up in places with no obvious relationship to each other. Whether the laps and details are involved, or the field membrane itself. Whether the surrounding membrane is still serviceable. Whether drainage is contributing. What existing roofing and underlying conditions are present, since those change what any new work involves — and some of them may only become apparent once an affected area is opened.
Every one of those is answered by looking at the roof rather than at its paperwork, and together they separate a contained repair from a wider conversation.
- Confined to one area, or scattered
- Laps and details, or the field membrane
- Surrounding membrane still serviceable
- Drainage contributing
Repairing an area, or replacing more
GoodVans Roofing installs, repairs and maintains torch-on roofing, so all three are genuinely on the table rather than one being the default.
Where a defect is bounded, its cause identifiable, and the membrane and details around it performing, work confined to that area may be appropriate. A lap that has opened in one location is a different proposition from similar conditions appearing in several.
Where conditions appear across unrelated areas, where drainage cannot be corrected without reworking the assembly, or where what sits under the membrane raises its own questions, a wider scope may need to be considered. There is no percentage or age at which that switches over. It follows from what the roof is actually doing.
When another route may suit better
Replacement is not the only alternative to repair. GoodVans Roofing applies roof coatings over existing commercial and industrial roofing systems, and where a coating is being considered, roof coatings and waterproofing explains that separate route.
And where what a building needs is tracking how a roof changes rather than responding to a single finding, roof asset management plans cover that ground.
What the work involves
GoodVans Roofing works to a set sequence on torch-on projects: the existing roof is inspected to assess whether torch-on is suitable for it, the surface is cleaned and primed, the membrane is heated and bonded section by section, every seam is checked and the roof tested for leaks, and the site is cleaned up and walked through with the client at the end, along with maintenance advice.
The inspection at the front matters more than it sounds. It is where the question of whether this system fits the building gets answered, rather than assumed from the fact that it is what is already up there.
Common questions
Is torch-on the same as modified bitumen?
Torch-on is one heat-applied form within the modified-bitumen family, so not all modified bitumen is torch-on. What distinguishes it is that the membrane is bonded to the surface beneath using a propane torch.
What does heat-applied actually mean for the finished roof?
That the membrane is bonded to the prepared surface by heat, and that adjoining sheets are lapped and bonded to each other in the same way. It also means the result depends on how the surface was prepared and how each lap was formed, neither of which can be judged by looking at the finished roof.
Can an existing torch-on roof be coated instead of replaced?
It may be possible, depending on the condition of the existing membrane and whether a coating system is compatible with it. That is a question to establish by assessment rather than assume, and the coatings page covers what it involves.
What gets checked when deciding whether torch-on suits a building?
The state of the existing roof is what GoodVans Roofing checks at the start of the process. Beyond that, the usual project factors apply as general context: how the roof drains, what penetrates it, what is already installed, and how it will be accessed afterwards.
Where to start
If you have a torch-on roof that is causing trouble and you are unsure whether it is the field membrane, the laps, the details or the drainage behind it, that is worth pinning down before choosing between a repair and something larger. Get in touch to have it assessed, or read more about GoodVans Roofing's torch-on roofing service.
