Inside a Commercial Roof Project on Bowes Road in Concord

We published a project film titled 261 Bowes Road, Concord on our YouTube channel, and the footage is linked from our gallery. Concord is part of the City of Vaughan, and the roofs there are low-slope industrial. This piece walks through how a project on that kind of building is sequenced and what constrains the work.

Where is Concord, and what does the roof stock look like there?

Concord is a community within the City of Vaughan, north of Toronto, and it is one of the denser industrial and commercial areas in York Region. Bowes Road runs through that industrial fabric. The buildings are the type that fill the corridor: single-storey and low-rise units, long clear-span bays, steel deck, and roofs that are flat or close to it, carrying rooftop mechanical units, exhaust fans, curbs and roof drains rather than any pitched surface.

Almost all of that stock is multi-tenant or owner-occupied industrial, which means somebody is working underneath the roof every day the crew is on it. Shipping doors are in use, forklifts are moving, and in many units product is racked to the underside of the structure. That single fact shapes every decision on the job before a roll of membrane leaves the truck.

For our full coverage of the municipality, including Concord and Woodbridge, see commercial roofing in Vaughan.

What happens before anything is priced?

The roof gets walked, and the assembly gets opened. On an industrial unit in this corridor the walk covers a predictable list:

• The system on the surface. SBS modified bitumen, a single ply such as TPO or EPDM, or an older built-up roof with aggregate. On many buildings of this age there is more than one roof present.
• Test cuts. A cut through membrane, cover board and insulation to the deck tells us how many layers exist, whether the insulation is dry, what the vapour barrier is doing, and what condition the steel deck is in. Nothing meaningful can be quoted without it.
• Drainage. Where the drains, scuppers and overflows sit, whether the roof actually falls toward them, and where the low spots are. Ponding is the standard finding on long-span industrial roofs.
• The perimeter. Parapets, cap flashing, gravel stop and edge metal. On a wide, exposed industrial roof the edge and corner zones take the highest wind uplift, and they are usually where the first failures show.
• Rooftop equipment. Curbs, exhaust fans, gas lines, conduit and pitch pockets, plus what the units below actually vent onto the roof.

All of that goes into a written scope with photographs so the owner or property manager can hand it to whoever approves the spend. The process is the same one described on our flat roof inspection page.

How is the work staged over an occupied industrial unit?

The controlling rule is simple: nothing is opened that cannot be closed watertight the same day. Everything else follows from it.

1. Sections. The roof is divided into areas that a crew can tear off, dry in and complete within a working day, with the tie-in landing at a defensible stopping point rather than mid-field.
2. Access and staging. Crane or hoist placement is agreed against the yard, the shipping doors and the truck traffic, because in this corridor a blocked dock is a bigger problem for the tenant than the roof was.
3. Interior protection. Where the deck is being exposed above racked product or production equipment, the area below is protected or cleared and coordinated with the tenant in advance.
4. Hot work control. Where torch-applied membrane is used, a hot work procedure applies, with a combustible-free zone and a fire watch maintained after the torches are shut down.
5. Daily close-out. Water cut-offs at every stop point, drains kept clear through the work, debris contained, and the roof left able to take rain overnight.

The full sequence for occupied buildings is set out on our commercial roof installation and replacement page.

What is different about working in this part of Vaughan?

Three things come up repeatedly on Concord industrial roofs.

Wind exposure. These are wide, low buildings with long uninterrupted roof fields and few surrounding obstructions. Uplift demand is highest at the perimeter and corners, which is why fastener density is increased in those zones and why edge metal detailing is not a place to economise.

Drifting snow. Where a lower roof meets a higher wall, or where mechanical screens and parapets interrupt the field, snow drifts and concentrates load well above the field value. The Ontario Building Code sets the design snow and rain loads through Supplementary Standard SB-1, and any question about whether a structure can carry what has accumulated is an engineer's call, not a roofer's.

Process exhaust. Industrial tenants change, and so does what they put through the roof. A unit that was a warehouse when the roof went on may now run a process that discharges grease, solvent vapour or heat onto the membrane. Membrane selection has to match what is actually landing on the roof today, which is one of the topics on our industrial roofing page.

What gets documented on a project like this?

An industrial roof is buried the moment the new membrane goes down, so the record made during the work is the only evidence anyone will ever have of what is underneath.

• Test cut photographs showing every layer of the original assembly.
• Deck condition once the tear-off exposes it, including any areas of corrosion, and what was done about them.
• Drain and scupper conditions before and after, and any tapered insulation or crickets added to correct a ponding area.
• Every flashing detail photographed as it was built, at parapets, curbs, penetrations and the roof edge.
• The completed assembly by layer, so the next contractor on the roof knows what they are cutting into.

On some projects we also film the work. The project film titled 261 Bowes Road, Concord is on our YouTube channel and is linked from the project gallery, which is the best place to see what a low-slope industrial roof looks like at each stage rather than reading about it.

Specifics of any individual building, including the assembly installed, the areas covered and the schedule, stay with the project record for that client rather than being published here.

What should a Concord building owner ask for before signing?

Whatever the building, the same short list separates a scope you can rely on from one you cannot.

• Has anyone opened the roof? A quote written from the surface is a guess about the insulation and the deck.
• Does the scope state the assembly layer by layer, including the vapour barrier, insulation type and thickness, cover board and attachment method?
• How is wind uplift addressed at the perimeter and corner zones, and what happens if the existing deck will not hold new fasteners?
• What is the drainage plan? If the roof ponds today, replacing the membrane without tapered insulation or additional drainage reproduces the same problem on a new roof.
• How is the building kept operating, and who talks to the tenant each day?
• What safety documentation is provided before mobilisation? WSIB coverage and certificates of insurance are provided on request.

To arrange a walk on a building in Concord, Woodbridge or anywhere else in Vaughan, call 416-456-0777 or use the free estimate form.