Commercial Roofing FAQ - Ajax, ON

How often should commercial roofs be inspected in Ontario?

We recommend bi-annual inspections for most commercial roofing systems—once in spring after the freeze-thaw cycle concludes, and again in fall before winter arrives. Ontario's harsh winters and temperature fluctuations create unique stresses on commercial roofing membranes, flashings, and drainage systems.

Buildings with HVAC units, heavy foot traffic, or older roofing systems may benefit from quarterly inspections to catch minor issues before they escalate into costly repairs.

What commercial roofing systems work best for Ajax weather conditions?

Several systems perform well in our climate:

• TPO and PVC membranes: Excellent heat-welded seams, UV resistance, and flexibility during temperature changes
• EPDM rubber roofing: Proven durability in freeze-thaw conditions with proper installation
• Modified bitumen: Strong performance in cold climates with multiple layers of protection
• Built-up roofing (BUR): Time-tested redundancy ideal for low-slope applications

The right choice depends on your building's structural capacity, slope, usage patterns, and budget.

Do I need permits for commercial roof replacement in Ajax?

Most commercial roofing projects require building permits from the Town of Ajax. Permit requirements typically apply to:

• Complete roof replacements and re-roofing projects
• Structural modifications or additions
• Changes to drainage systems
• Installation of rooftop equipment requiring penetrations

Professional commercial roofers handle permit applications and ensure work meets Ontario Building Code requirements. This protects your investment and ensures compliance during future property transactions or insurance claims.

What causes ponding water on flat commercial roofs?

Ponding water—defined as water remaining on a roof surface 48 hours after precipitation—can result from:

• Inadequate roof slope or drainage design
• Deflection in roof decking or structural members
• Blocked or undersized drains and scuppers
• Settling of the building over time

Ponding accelerates membrane degradation and increases weight load on your structure, especially during winter when water freezes. Professional assessment can identify the root cause and recommend solutions ranging from tapered insulation systems to drain modifications.

How long do commercial roofs typically last?

Service life varies by system type and maintenance quality:

• TPO/PVC single-ply membranes: 20-30 years
• EPDM rubber roofing: 20-25 years
• Modified bitumen: 15-20 years
• Built-up roofing: 15-30 years depending on layers
• Metal roofing systems: 30-50+ years

Regular maintenance, prompt repairs, and proper installation significantly extend these estimates. Neglected roofs often fail prematurely, while well-maintained systems can exceed their rated lifespan.