Warehouses and industrial bays
Large, open TPO or SBS roofs in Foothills, Great Plains, Eastlake and Highfield, usually with rooftop units, gas lines and skylights to detail around. Phasing by bay keeps tenants operating.
Commercial Roofing
Two-ply SBS, TPO, EPDM and standing-seam metal for warehouses, strip malls, condo boards and industrial bays across Calgary and southern Alberta.
What we do
A commercial roof in Calgary has to absorb 5 cm hail in August, then flex through thirty-degree chinook swings in January. Most premature failures we open up are not material failures. They are detail failures at curbs, drains and parapets.
We work on low-slope and steep-slope commercial buildings between roughly 2,000 and 60,000 square feet: light industrial bays in Foothills and Great Plains, strip retail along Macleod Trail and 16 Avenue NE, multi-family and condo blocks in the inner city, and shops and shops-with-suites in Rocky View County. On every one of them the owner of Mountain Standard walks the roof himself before a number is written down, because a commercial quote built from a satellite image is a guess and a guess is what gets change-ordered later.
A written assessment with photos, core samples where needed, remaining service life, and a repair-versus-replace recommendation you can hand to a board or a lender.
We photograph and mark every hail hit, split and puncture, then package it so your adjuster can scope the loss properly. We handle the claim paperwork and document the damage for your adjuster.
On large buildings we can section the roof and do it over two seasons, worst area first, so cash flow and tenant operations both survive.
Your written quote sets out the materials, installation scope and applicable warranty. Real numbers, same system, same warranty.
How it runs
Commercial work fails on logistics more often than on shingles. Tenant access, crane and hoist placement, gas line shutdowns, garbage bin location, roof traffic during business hours — we plan all of it before day one and put it in writing so a property manager is not fielding surprise calls from tenants.
The owner measures, probes soft spots, checks drains, curbs, parapets and the deck, and pulls a core if the assembly history is unknown.
You get a line-item scope: tear-off or overlay, insulation value, membrane system, flashing details, warranty terms and cost for each option.
Access, hoisting, noise windows and safety plan confirmed with the property manager.
Daily site photos, a final walkthrough with you on the roof, warranty paperwork, and clear guidance on annual maintenance.
Nine out of ten commercial leaks we chase in Calgary start at a penetration, not in the field of the membrane. Rooftop units installed by a mechanical trade with no roofer on site are the single biggest offender: the curb flashing gets cut, folded back and re-sealed with caulking instead of being properly stripped in. Caulking has a two-to-four-year life in a climate with 30-degree chinook swings. Membrane flashing has twenty.
The second offender is drainage. Calgary's snow does not melt evenly — a chinook melts the sunny half of a roof while the shaded half stays frozen, so meltwater runs to a drain that is still plugged with ice and then finds a lap seam instead. On flat roofs we check that every drain has a working strainer, that scuppers are clear, and that there is a secondary overflow path. On parapet-heavy buildings we look hard at the wall-to-roof transition, because that is where ponded meltwater ends up.
The third is wind. Calgary sits in a high-wind corridor and gusts regularly strip poorly fastened edge metal, which then peels membrane behind it. Correct fastener pattern, proper edge-metal gauge and a compliant perimeter attachment zone cost a few hundred dollars more and prevent a five-figure repair. We spec them by the book on every low-slope job.
There is no single best commercial roof for Calgary. There is a best roof for a given building, budget and rooftop. Two-ply SBS modified bitumen is what we install most; TPO is the right call on large, open roofs; EPDM suits small decks; metal suits sloped bays and ag buildings. The table below is how we explain the trade-offs to owners and boards, with the climate factors that actually matter here: freeze-thaw, high-altitude UV, hail, Chinook wind uplift and snow load.
| System | Best for | Typical service life | Calgary pros and cons | Maintenance |
|---|---|---|---|---|
| Two-ply SBS modified bitumen (torch-on base and cap sheet) | Roofs with lots of curbs, parapets and foot traffic; strip retail, multifamily, schools | Manufacturers such as Siplast cite 20 to 30 years or more with proper installation and maintenance | Two layers of reinforced, rubber-modified asphalt handle freeze-thaw and hail better than any single-ply, and details at parapets are easier to do well. Granulated cap sheet resists UV. Heavier than single-ply, so we confirm deck capacity where snow load is already high. Open flame means a fire watch and no torching directly on combustible details. | Twice-yearly walk, clear drains, re-seal exposed flashing terminations, patch cap-sheet blisters early. Easiest system to repair cleanly after hail. |
| TPO (heat-welded single-ply, usually white) | Large, open warehouse and industrial roofs; buildings where summer cooling load matters | Industry consultants put TPO at roughly 20 to 30 years (Terrapin Consulting Group), and thickness matters | Reflective surface lowers rooftop temperature and cooling load. Welded seams are strong when done right, but every seam and detail is a single layer, and Calgary hail bruises thin TPO. Cold-weather installation is limited: Carlisle rates even its self-adhering TPO to about -4 °C, so shoulder-season scheduling is real. Light weight helps on older decks. Mechanically fastened perimeters need a wind-rated assembly for Chinook gusts. | Twice-yearly walk, seam probe, check for membrane scuffing under mechanical units, keep the surface clean so it stays reflective. |
| EPDM (black rubber single-ply, adhered or ballasted) | Small low-slope decks, additions, some apartment blocks | Manufacturer Holcim Elevate states service life can exceed 50 years; we plan on far less where hail and traffic are heavy | Stays flexible in cold and rides out freeze-thaw well. Black surface absorbs heat, which helps melt in winter but adds summer load. Seams are taped, not welded, and seam tape is the usual failure point. Field research shows single-ply membranes are hail resistant when new but lose strength and grow brittle as they age (Haag / IIBEC). | Twice-yearly walk, seam and flashing checks, remove debris, re-adhere lifted edges. |
| Metal (standing-seam or screw-down steel) | Sloped commercial bays, shops, agricultural and equestrian buildings | The Metal Construction Association field study projects 60 years or more for coated-steel standing seam with maintenance | Sheds snow and does not pond. Panels take large hail as cosmetic dents rather than leaks, but insurers may treat dents differently, so read the policy. Exposed fasteners back out with thermal cycling and are the main leak source on screw-down roofs. Standing seam handles Chinook uplift well when clips and edge details are done to spec. | Annual walk, fastener and sealant check, clear valleys and snow guards, touch up scratched coating. |
Whichever membrane you pick, we detail it to the Alberta Roofing Contractors Association Roofing Application Standards Manual, and we spec perimeter attachment from wind-tested assemblies rather than guessing, because Calgary edge metal that lifts once takes the membrane with it. On drainage we use the NRCA rule: no ponding water 48 hours after rain in drying conditions. If your existing roof fails that test, tapered insulation is part of the scope, not an upsell.
Who we work for
Most of the commercial roofers in Calgary specialise in one kind of building. We size the system, the crew and the schedule to the building in front of us.
Large, open TPO or SBS roofs in Foothills, Great Plains, Eastlake and Highfield, usually with rooftop units, gas lines and skylights to detail around. Phasing by bay keeps tenants operating.
Parapet-heavy roofs with a dozen tenants, a dozen HVAC curbs and one property manager. We schedule around opening hours and put access, noise and bin locations in writing first.
Low-rise walk-ups and townhouse complexes from the Beltline to Panorama Hills. You get a written condition assessment your board can attach to a reserve fund study, plus a repair-versus-replace recommendation.
Mixed steep and low-slope sections, older decks and tight budgets. We often phase the worst section first and document the rest for future planning.
Work is scheduled for summer or breaks, with a safety plan and fenced staging. Two-ply SBS is the usual answer because of foot traffic and the number of penetrations.
Metal and screw-down steel on barns, arenas and shops across Rocky View, Foothills County and out to Strathmore and High River. Fastener replacement and hail assessments are the common call.
A full commercial roofing replacement is the right answer when core samples show wet insulation across a meaningful share of the roof, when the membrane has widespread splits or hail fractures, when the deck is deteriorated, or when the roof already carries two layers. Tearing off also lets you fix slope, upgrade insulation and get a clean manufacturer warranty. We break down real Calgary numbers in our guide to commercial roof replacement cost in Calgary.
Restoration is the right answer when the membrane is sound but tired: chalking, minor surface crazing, a handful of isolated leaks at details, dry insulation on every core. In that case a targeted repair program plus a protective coating buys years for a fraction of the cost. For sloped asphalt roofs on commercial and multifamily buildings, our is the restoration option we are certified to apply. On low-slope membranes we talk through coating options honestly, including when a coating is a waste of money.
Ponding. Decks settle, drains sit high, and water that stays more than 48 hours accelerates membrane ageing and voids most warranties. In winter that pond freezes, expands and works every seam it touches.
Seam failure. Taped EPDM seams and cold-welded TPO seams open up under freeze-thaw. Two-ply SBS laps are the most forgiving, but a lap torched in a cold wind without proper bleed-out will fail too.
Flashing at parapets. Base flashing that is too short, unsupported at the cant, or terminated with caulking instead of a metal counterflashing is the single most common leak we find on Calgary strip retail.
Hail-fractured membranes. The August 5, 2024 storm produced nearly $2.8 billion in insured losses and more than 130,000 claims according to the Insurance Bureau of Canada. On flat roofs the damage is often invisible from the ground: fractured cap-sheet granules, bruised TPO over insulation joints, and cracks that only open the following winter. We photograph and mark every hit and we handle the claim paperwork.
Drain and scupper icing. A Chinook melts the south half of a roof while the drains on the shaded side stay frozen. Meltwater backs up over flashing heights and finds the first lap. Heat-traced drains, working overflow scuppers and clear strainers prevent most of it. See our flat roofing page for the residential version of the same problem.
Get a real number, not a guess
Free inspection, written scope with photos, and a repair-versus-replace recommendation you can take to your board or your insurer. The owner does the assessment personally.
Request Your Free AssessmentQuestions homeowners actually ask
Sometimes. If the existing assembly is dry, well adhered and within the allowed number of layers, an overlay saves real money. If we find wet insulation on a core sample, an overlay just buries the problem and voids most manufacturer warranties, so we will tell you no and show you why.
Yes. We inspect, photograph and mark the hail damage, put the scope in writing, and we handle the claim paperwork so your adjuster is working from real measurements. Coverage decisions belong to your insurer, but the documentation they need is what we provide.
We phase the roof in sections so the building is never left open, stage material and the bin away from customer entrances, work around tenant hours where noise or odour matters, and give you a written stage-by-stage schedule before we start. If rain is going to push a stage, you hear it from us the same day.
On paper, standing-seam metal, then EPDM, then two-ply SBS and TPO. In practice the assembly under the membrane, drainage and detailing decide it. A two-ply SBS roof with real slope, clean drains and properly stripped-in curbs will outlast a premium single-ply that ponds and was detailed with caulking. Hail and rooftop traffic shorten every system, and SBS is the easiest to repair after both.
Twice a year, spring and fall, plus after any major hail or wind event. That matches the industry guidance published by the Single Ply Roofing Industry association, and it is what most manufacturer warranties expect. In Calgary the fall visit matters most: clear drains and scuppers before freeze-up and you avoid most Chinook leaks.
Both. We do full tear-off and commercial roofing replacement in two-ply SBS, TPO, EPDM and metal, as well as repairs, restoration coatings and hail documentation. Every job starts with the same owner-led assessment, and you get replacement and repair pricing side by side when both are real options.
Most commercial buildings need more than one of these. We do them all in house.
Owner-led, no subcontractors
Tell us the building, the square footage and what is going wrong. The owner reviews every request and follows up within one business day with next steps and a time to walk the roof.
Contact us to arrange an inspection
Pick a slot and we come to your property for a free on-site inspection. This is an in-person visit — not a phone or video call.
Book On-Site Inspection★★★★★ 5.0 out of 5 — 10 Google reviews
Every review below is a verified Google review of Mountain Standard Roofing Ltd. Every job comes with a lifetime workmanship warranty and a clear written scope.
★★★★★
“Mountain Standard Roofing handled my storm damage roof replacement perfectly. They worked directly with my insurance company, handled all the paperwork, and made the entire process stress-free. The crew was professional, efficient, and left my yard clean.”
Nikki Rick — Google review
★★★★★
“John and his team were awesome to deal with. He did my roof and siding and they finished a day ahead of schedule. Not only was the service awesome but the price was much better than competitors.”
Kristoffer — Google review
★★★★★
“The owner John is very communicative and always took time to answer our questions. Our roof was re-done in the agreed timeline and for the agreed upon price. Would highly recommend doing business with Mountain Standard Roofing.”
Ryan Van Boven — Google review