OYH Roofing

At a glance

In this Welland commercial roofing project, OYH Roofing installed an IKO 2-ply modified bitumen roofing system across 52,300 square feet at 777 Niagara St in Welland, Ontario. It was a full-system installation on a large low-slope commercial roof, and the finished roof carries a 20-year system warranty.

Project details

This Welland commercial roofing project covered a 52,300 square foot low-slope roof in the Niagara Region. Here is the job in one table.

Source: OYH Roofing project record for 777 Niagara St. As of October 2026.
ItemDetail
Location777 Niagara St, Welland, Ontario (Niagara Region)
Building typeCommercial
Roof area52,300 sq ft
ServiceModified bitumen roofing installation
SystemIKO 2-ply modified bitumen (base sheet and cap sheet)
Warranty20-year system warranty
Welland commercial roofing project at 777 Niagara St, aerial view of the 52,300 sq ft modified bitumen roof
The finished roof at 777 Niagara St, Welland.

Why modified bitumen for Welland commercial roofing?

Modified bitumen suits Welland commercial roofing on large buildings because its two layers give a second line of defence against leaks, it stands up to foot traffic from service crews, and it stays flexible through Niagara freeze-thaw cycles.

It is an asphalt-based membrane reinforced with polyester or fiberglass and modified with polymers. On a roof this size, the second ply matters: if the cap sheet is ever damaged, the base sheet is still there. That redundancy is the main reason building owners with big, busy roofs choose it. It is not the right answer for every building, so here is how it compares with the other systems we install.

General comparison of flat roofing systems OYH Roofing installs, for owners weighing Welland commercial roofing options. The right system depends on the building. As of October 2026.
SystemLayersWhere it winsWhere another system wins
2-ply modified bitumenBase sheet plus cap sheetToughest underfoot, two layers of protectionHeavier; a white TPO roof reflects more summer heat
TPOSingle ply, hot-air welded seamsReflective white surface, welded seamsOne layer; thicker 60 mil sheets are needed for busy roofs
EPDMSingle ply rubberVery flexible in cold weather, long track recordSeams are taped or adhered, not welded

Our modified bitumen vs TPO guide also covers whether an old modified bitumen roof can be switched to TPO.

How is a 2-ply modified bitumen roof installed?

A 2-ply modified bitumen roof goes down in two layers: a base sheet bonded to the prepared roof, then a granulated cap sheet on top that protects the membrane from sun and weather.

On a Welland commercial roofing job of 52,300 square feet, the membrane itself is the easy part. The work that decides how long the roof lasts is at the details: seam overlaps, flashings at curbs, parapets and rooftop units, and the connections at every drain. Industry guidance from the National Roofing Contractors Association says the same thing about low-slope roofs. Using one manufacturer's matched system, here from IKO, rather than mixing products, is also what makes a system warranty possible.

Close aerial view of the modified bitumen cap sheet on the Welland commercial roof
Detail of the finished cap sheet surface.

What does the 20-year system warranty cover?

This Welland commercial roofing project carries a 20-year system warranty, which is backed by the manufacturer on the roofing system as installed rather than on a single roll of membrane.

What a system warranty covers, and what the owner has to do to keep it valid, is set by the manufacturer's written terms. That usually includes regular inspections and keeping records of any work done on the roof, as on any Welland commercial roofing project. If you own a building with an OYH roof, ask us for the warranty document for your project.

How do you maintain a modified bitumen roof?

A modified bitumen roof needs an inspection at least twice a year, in spring and fall, plus a check after major storms.

Typical maintenance plan for a low-slope modified bitumen roof, based on the NRCA recommendation of at least two inspections a year. As of October 2026.
WhenWhat to check
Spring, after the snow meltsSeams, flashings, drains, any damage from ice or ponding
Fall, before winterClear drains and debris, check flashings at curbs and parapets
After major stormsWind or debris damage, blocked drains
Every rooftop service visitCrews stay on walkways; log who was on the roof and why

Building owners should not walk the roof themselves, especially in winter or wet weather. Book the inspection and let a roofing crew do it with proper fall protection. We offer inspections to every Welland commercial roofing client.

Photos of the finished roof

Drone photos of this Welland commercial roofing project, taken after the work was finished.

Welland commercial roofing and the Niagara Region

OYH Roofing handles Welland commercial roofing from its Oakville base and installs industrial, commercial and institutional flat roofs across Ontario, including the rest of the Niagara Region.

Our commercial roofing services cover modified bitumen, TPO, PVC, EPDM and built-up roofing, plus inspections and commercial roof leak repair. The same IKO 2-ply system went on the City of Mississauga building at 3185 Mavis Rd, and you can see the rest of our work on the completed projects page.

Planning Welland commercial roofing work?

For Welland commercial roofing work, tell us about the building and we will set up a free roof assessment and a written quote.

Call 1-833-775-7663Request an assessment

Frequently asked questions

How long does a modified bitumen commercial roof last?

A modified bitumen commercial roof commonly lasts 20 years or more when it is installed as a full system and inspected twice a year. The Welland roof at 777 Niagara St carries a 20-year system warranty, which reflects that expected service life. Blocked drains, foot traffic damage and skipped inspections are what usually shorten it.

Is modified bitumen a good choice for flat roofs in Welland?

Modified bitumen is a good choice for large flat roofs in Welland because its two layers resist leaks and ponding water and the polymer-modified asphalt stays flexible through Niagara freeze-thaw cycles. A white TPO roof reflects more summer heat, so the best system depends on the building and how the roof is used.

What is a 2-ply modified bitumen roof?

A 2-ply modified bitumen roof is a flat roofing system made of two layers of polymer-modified asphalt membrane: a base sheet bonded to the roof and a granulated cap sheet on top. The second layer gives a backup against leaks, which is why it is common on large commercial and industrial roofs.

What does a 20-year system warranty mean?

A 20-year system warranty means the manufacturer backs the roofing system as installed for 20 years, subject to its written terms. Those terms usually require regular inspections and records of any rooftop work. Ask your roofer for the actual warranty document, because coverage differs between manufacturers and warranty levels.

Does OYH Roofing work in the Niagara Region?

OYH Roofing works in the Niagara Region, and the 52,300 square foot roof at 777 Niagara St in Welland is one example. The company is based at 2120 Speers Rd in Oakville and installs, repairs and inspects industrial, commercial and institutional flat roofs across Ontario. Call 1-833-775-7663 to book an assessment.

Karol Rajkowski, Vice President of OYH Roofing

Karol Rajkowski

Vice President · OYH Roofing

Karol Rajkowski is Vice President of OYH Roofing, an Oakville-based ICI flat-roofing contractor whose projects include the City of Mississauga building at 3185 Mavis Rd and the Marriott Hotel in Vaughan. Learn more about the OYH team.

Sources

OYH Roofing, 2120 Speers Rd, Oakville, ON L6L 2X8 · 1-833-775-7663 · info@oyhroofing.ca