Chemical and grease resistance
Handles the fats, oils and many chemicals that soften EPDM and asphalt.
Flat roof system
PVC Roofing in Edmonton
A heat-welded single-ply membrane that stands up to grease, oil and chemicals. It costs more, and on the right roof it is worth it.
Overview
PVC roofing is the membrane of choice when something on your roof would attack other materials. PVC (polyvinyl chloride) is a thermoplastic sheet with hot-air welded seams, like TPO, but it resists animal fats, oils and many industrial chemicals far better. For Edmonton food plants, restaurants, and process buildings with chemical exhaust, that resistance decides the roof.
It is not the default for a plain warehouse. PVC costs more than TPO or EPDM, it needs separation from asphalt and polystyrene, and it slowly loses flexibility as it ages. Where grease or chemicals are present, those trade-offs are worth it. Rain Roofing installs Sika Sarnafil PVC systems.
Welded seams
Hot-air welds fuse overlaps into one sheet, with no tape or adhesive at the laps.
Long warranties
System warranties up to 30 years are available on qualifying assemblies.
How a PVC roof works
PVC membranes contain plasticizers that keep the sheet flexible, and a polyester or glass reinforcement that holds it dimensionally stable. Most commercial sheets are 50 to 80 mil. Because the seams are welded, a good PVC roof behaves like one continuous sheet.
Compatibility shapes the whole assembly. Asphalt and polystyrene both draw plasticizer out of PVC, so the membrane can never sit directly on an old bitumen roof or on EPS or XPS insulation. A separator sheet or the right cover board solves it, and getting that layer right is one of the details we check first on any PVC recover.
- Deck and vapour retarder.
- Insulation, typically polyiso.
- Cover board, plus a separator sheet over asphalt or polystyrene.
- Reinforced PVC membrane, fastened or adhered.
- Welded seams and PVC-coated metal flashings.
PVC roofing in Edmonton's climate
Welding helps here, as it does with TPO: seams can be made in cool spring and fall weather that would stall adhesive-based systems. New PVC handles cold and hail reasonably well, especially over a cover board.
The long-term concern is plasticizer loss. Over many years, PVC slowly gives up the additives that keep it flexible, and an old PVC roof can become brittle enough to crack under hail or a dropped tool in deep cold. Good membranes, proper thickness and regular inspections manage that risk.
Where PVC is the right choice
Choose PVC when grease, oil or chemicals reach the roof: restaurants and food courts in retail plazas, meat and food processing plants, labs, and process buildings in the Industrial Heartland and Nisku. It is also a good fit where fire performance is a priority.
On a plain warehouse with clean exhaust, the extra cost does not buy much. TPO or SBS will serve as well for less. PVC also cannot touch asphalt directly, so recovering an old tar and gravel or SBS roof with PVC always needs a separator layer.
Maintaining a PVC roof
Grease is the main maintenance item on restaurant and food plant roofs. Even PVC lasts longer when grease traps around exhaust fans are cleaned and replaced on schedule. Spring and fall inspections should also check seams, flashings and the membrane around rooftop units, and note any stiffening or surface cracking on older sheets.
Warranty options for PVC roofs
Sika Sarnafil offers PVC system warranties up to 30 years on qualifying assemblies, with terms tied to membrane thickness and attachment. Some PVC warranties exclude damage from unmaintained grease build-up, so we explain those terms before you sign. Rain Roofing adds a 10-year workmanship warranty on every PVC install.
Repair or replace: signs to watch
PVC welds well for most of its life, so repairs are clean and permanent. Replacement comes into view when the membrane itself has aged.
- Shattering or cracking at punctures, a sign of plasticizer loss.
- Shrinkage pulling at flashings and corners.
- Surface crazing over large areas.
- Wet insulation found by a moisture survey.
Inside the assembly
What goes under the PVC surface
Every layer has a job. Skip one, or install it carelessly, and the roof fails early. This is the assembly we build and warranty.
- 07Cap sheet or membraneThe weathering surface: granulated SBS cap sheet, or a heat-welded TPO, PVC or EPDM membrane.
- 06Base sheetThe first waterproofing ply, fully bonded and lapped at every seam.
- 05Cover boardA hard, flat surface that protects the insulation from foot traffic and hail.
- 04Tapered insulationBuilt-in slope that moves water to the drains so it never sits and ponds.
- 03InsulationPolyiso boards, staggered so no joint lines up and heat cannot short-circuit.
- 02Vapour barrierStops warm, moist indoor air from condensing inside the insulation in January.
- 01Steel deckThe structure. We check fastening, rust and deflection before anything goes on top.
Process
How we install it
Exposure survey
We identify every exhaust fan and process vent, what it discharges, and where it lands, so the membrane and flashings match the exposure.
Insulation and separation
Insulation and a cover board go down. Where the old roof is asphalt or the insulation is polystyrene, a separator sheet keeps them away from the PVC.
Membrane attachment
PVC sheets are mechanically fastened, adhered or attached with induction-welded plates to meet the wind and warranty spec.
Hot-air welding
Seams are fused by robotic and hand welders, with settings adjusted to the day's temperature and checked with test welds.
Flashings and grease protection
PVC-coated metal and membrane flashings finish curbs and edges; grease containment goes in around kitchen exhaust fans.
Seam probe and inspection
Every seam is probed and the roof is inspected for the manufacturer warranty before handover.
Warranty
Three layers of cover on every roof
Our workmanship, an independent ARCA certificate, and the manufacturer's system warranty, each backed by a different party.
Spring and fall inspections every year keep all three warranties valid. Included in every Rain maintenance program.
Questions
What facility managers ask us
Is PVC worth the extra cost?
Where grease, oil or chemicals reach the roof, yes. Other membranes can fail early under that exposure. On a roof with clean exhaust, TPO or SBS usually gives better value.
What is the difference between PVC and TPO?
Both are white, heat-welded single-ply sheets. PVC resists grease and chemicals better and has a longer history; TPO costs less and does not rely on plasticizers. The exposure on your roof usually decides it.
Can PVC go over our existing tar and gravel roof?
Yes, with a separator sheet or cover board between them, because asphalt and PVC are not compatible. The gravel and loose material come off first, and the insulation has to be dry.
Does PVC get brittle in the cold?
New PVC handles Edmonton winters well. Over many years it slowly loses plasticizer and becomes less flexible, which is why older PVC roofs need careful inspection after hail.
Our restaurant tenant's exhaust is damaging the roof. What should we do?
Start with grease containment at the fan and a repair of the damaged area. If the existing membrane is EPDM or asphalt, replacing that section with PVC stops the problem from returning.
How long does a PVC roof last in Edmonton?
Typically 25 to 30 years or more. Membrane thickness, grease control at exhaust fans and regular inspections make the biggest difference. Thicker sheets hold their plasticizer longer and stay flexible into later years.
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Talk to the crew that stands behind the roof
Send us drawings, a spec or just an address. You get a clear scope, a written warranty and a roofer who answers the phone in a storm.