Commercial roofing for Calgary buildings
Commercial roofing covers the repair, restoration and replacement of roofs on buildings where people work, shop, worship or live together, and every decision has to account for the occupants below. A leak over a retail floor or condo hallway affects tenants, inventory and trust.
We work with property managers, building owners, condo boards and small business owners on:
- Low-rise retail and strip plazas, where long flat roofs and many tenants make phasing important.
- Office buildings, where noise, access and occupant communication matter.
- Light industrial buildings and warehouses, with large roof areas, skylights and exhaust fans.
- Multi-family and condo buildings, often combining membrane sections with sloped shingle roofs.
- Churches and community buildings, which frequently mix roof types and run board-approved budgets.
Commercial roof systems
Most commercial buildings in Calgary sit under a low-slope membrane system, though many multi-family buildings add sloped roof sections. Knowing what is on your roof is the first step to maintaining it properly.
TPO
A single-ply thermoplastic membrane, usually white, with hot-air welded seams. Common on newer retail and industrial roofs.
EPDM
A synthetic rubber membrane that stays flexible in deep cold. Seams use tapes or adhesives, so seam condition is the thing to watch.
Modified bitumen
Asphalt-based sheets reinforced with polyester or fibreglass, installed in layers. It is tough, tolerates foot traffic well and is a frequent choice around busy rooftop equipment.
Built-up roofs
The traditional multi-ply roof of felts and asphalt, often finished with gravel. Many older Calgary commercial buildings still have one, sometimes with later layers on top.
Metal roofing on commercial buildings
Standing seam and exposed-fastener panels suit sloped commercial roofs. Metal sheds snow and lasts, but fasteners and panel laps need periodic attention.
Sloped shingle roofs on multi-family
Townhouse complexes and low-rise condos often have pitched shingle roofs over units with flat sections over corridors or entries. Both need to drain and flash together cleanly.
Common commercial roof problems in Calgary
The most common commercial roof problems in Calgary come from water that cannot drain, details that move and weather that swings hard between seasons.
- Ponding and poor drainage. Standing water speeds membrane wear and adds weight, often from deck deflection or blocked roof drains.
- Seam and flashing failures at parapets. Parapet walls, edge metal and wall flashings move with temperature swings, and open laps there are a leading leak source.
- Rooftop units and penetrations. Curbs, pipe boots, conduit and exhaust fans all cut through the membrane. Each one is a detail that has to stay sealed.
- Blistering. Trapped moisture or air between layers expands in summer heat, lifting the membrane and eventually cracking it.
- Hail punctures. Calgary sits in Canada’s most active hail belt. Hail can fracture aged membranes, crack gravel-surfaced roofs and dent metal.
- Snow loads and drifting. Wind piles snow against parapets, higher walls and rooftop units, concentrating weight in specific spots.
- Ice at drains. Meltwater refreezes around drains and scuppers, blocking the only way water can leave the roof.
- Rooftop foot traffic from trades. Mechanical, electrical and telecom contractors walk, kneel and drop tools on the membrane. Without walkway pads, damage builds quietly.
Repair, restore, recover or replace?
The right option depends on how much of the roof is failing and whether the insulation underneath is still dry. Here is how the choice usually breaks down:
| Situation | Repair | Restore | Recover | Replace |
|---|---|---|---|---|
| Damage extent | A few seams, flashings or punctures | Surface wear across the roof | Membrane at end of life | Widespread failure |
| Insulation | Dry | Dry | Mostly dry and sound | Wet in large areas |
| Existing layers | Any | One sound system | Room for one more layer | Multiple layers already |
| Disruption | Minimal | Low | Moderate | Highest |
| Planning horizon | Next season | Several more years | Long term | Long term |
Restoration means cleaning, repairing and coating a worn but watertight membrane. A recover adds a new membrane over the old roof where the structure allows. Replacement strips to the deck, the only fix for saturated insulation. Our roof replacement page explains the tear-off side in more depth.
Planning roof work around tenants and operations
Planning roof work around tenants means deciding, before anyone climbs a ladder, when each section will be open, where materials go and who needs to know.
- Scheduling. Split larger roofs into phases so only one section is exposed at a time, and schedule tear-off around business hours or quiet periods where possible.
- Noise and odours. Tear-off and fastening are loud, and some adhesives have odours. Air intakes on rooftop units may need to be closed or filtered during certain steps.
- Access and staging. Agree where bins, lifts and any crane will sit, and how deliveries and fire lanes stay clear.
- Protecting entrances and parking. Cordon off drop zones and keep safe routes into the building.
- Communication with occupants. Tenants and residents get notice before each phase, with dates, affected areas and a contact person.
- Rooftop units and trades. Units may need disconnecting, lifting or new curbs, so mechanical contractors are coordinated in advance.
Calgary conditions for commercial roofs
Calgary’s climate shapes when and how commercial roofs should be worked on, and it rewards owners who plan ahead.
Budgeting and capital planning
The best way to budget for a commercial roof is to know its condition years before it fails, so spending can be spread out instead of arriving as an emergency.
A condition assessment documents each roof section, its system, visible defects, drainage issues and likely remaining life. With that picture, owners can plan targeted repairs this year, restoration or recover in a few years, and replacement further out. For condo corporations, that timeline feeds straight into reserve fund planning.
Documentation matters too. Boards and owners approve work more readily with photos, a clear written scope and an explanation of options, and the same scope makes proposals easier to compare.
Our commercial roofing process
Our commercial roofing process keeps each stage visible to the property manager or board:
- Site visit and roof walk. We review access, roof sections, drainage, rooftop units, parapets and any areas with a leak history.
- Moisture investigation where needed. The industry uses core cuts and moisture detection methods to find wet insulation, which helps decide between recover and replacement.
- Written scope. The recommended work, roof system, phasing and exclusions are set out in writing.
- Scheduling and safety planning. We plan phases, staging, fall protection, drop zones and tenant notices around your building’s operations.
- Execution in phases. Work is phased section by section and planned around the forecast so the building stays protected.
- Daily cleanup. Debris, fasteners and packaging are cleared from the roof and grounds each day.
- Closeout documentation and photos. You receive photos and a summary of the completed work for your building records.
Maintaining a commercial roof
Maintaining a commercial roof mostly means keeping water moving and catching small problems early. A simple seasonal checklist for property managers:
- Spring: clear roof drains and scuppers, remove debris and look for ponding and open seams at parapets.
- Summer: check rooftop unit areas after service visits and add walkway pads where trades walk.
- After hail: check membranes, metal and skylights, and take dated photos.
- Fall: clear drains before snow and confirm edge metal and flashings are secure.
- Winter: manage snow with care. Shovels puncture membranes, so leave a protective layer.
Insurance and commercial roofs
Storm damage to a commercial roof may be covered by the building’s insurance, but policies vary widely and coverage decisions belong to the insurer. After a hailstorm or windstorm, record the date, photograph damage on the roof and inside, and report the claim promptly. We can document what we find on the roof, but we make no promises about what any policy will pay.
What affects commercial roofing cost
Commercial roofing cost depends on the roof’s size, system and how the work fits around the building’s operations. The main factors are:
- Roof area, measured in squares, one square being 100 sq ft.
- Roof system, such as TPO, EPDM, modified bitumen or metal.
- Insulation and cover board needed to meet current requirements or replace wet material.
- Tear-off and disposal, especially with multiple existing layers.
- Drainage corrections, such as tapered insulation or added drains.
- Rooftop units and penetrations needing curbs, flashings or temporary disconnection.
- Access, crane and staging requirements.
- Phasing around tenants, which adds mobilizations.
- Season, since cold can limit certain steps.
For more on how roof size, layers and materials shape pricing, see our roof replacement cost guide for Calgary.
Related services
Commercial roofing sits within our replacement work. If the roof has reached the end of its life, start with roof replacement. Adding a roof to a building or section that never had one is covered on roof installation, and new construction projects are explained on new roof.
To get started, request a free roof inspection or contact us.