Buyer’s Roof Inspection Checklist (Before Purchasing a Home) — ROOFNOW™

Before buying a home in Ontario, the roof is one of the most important systems to evaluate. Most roofing issues are invisible to the untrained eye — and repairs can cost anywhere from $5,000 to $35,000+. This engineering-based checklist helps Ontario homebuyers identify hidden roof problems, structural risks, attic moisture issues, and long-term durability concerns.

1. Determine the Roof Age & Replacement History

• Ask the seller for the exact roof age (year installed)
• Request all roofing invoices and warranty documents
• Confirm if it was a full replacement or just patch repairs
• Check if previous leaks were professionally resolved
• Determine if materials match the claimed age

2. Identify the Roofing Material

• Asphalt shingles (most common, 10–15 year lifespan in Ontario)
• Exposed-fastener metal (watch for screw back-out)
• Steel interlock shingles
• Concrete tiles
• Cedar shake (rare, expensive to maintain)

If asphalt is older than 10–12 years, replacement is usually approaching.

3. Exterior Roof Evaluation (Ground Level)

• Look for missing, loose, or lifted shingles
• Check for uneven or wavy roof lines (decking problems)
• Scan for dark patches or bald asphalt areas
• Look for granule piles at bottom of downspouts
• Check metal roofs for rust or exposed fasteners
• Examine ridge caps for cracks or separation

4. Roof Edge & Eave Condition

• Lifted shingles along edges (wind damage indicator)
• Ice dam staining or history of winter leaks
• Soffits sagging, loose, or blocked
• Eavestroughs pulling away or overflowing
• Water stains under roof edges

5. Valley & Transition Inspection

• Valley metal exposed or cracking
• Shingles slipping inside valleys
• Leaf or debris buildup (causes overflow during storms)
• Interior staining under valleys (big red flag)

6. Flashing & Penetrations (Most Common Leak Source)

Flashings cause over 60% of all roof leaks in Ontario homes.

• Chimney flashing separation or rust
• Skylight flashing loose or unsealed
• Plumbing vent flashing cracked or brittle
• Bathroom & kitchen exhaust vents improperly sealed
• Wall step-flashing exposed or displaced
• Sealant dried, cracked, or missing entirely

7. Gutters, Downspouts & Water Drainage

• Check for granule buildup in gutters
• Ensure downspouts direct water away from foundation
• Gutters not sagging or leaking
• No signs of overflow staining on siding

8. Attic Inspection (Where 90% of Roof Problems Start)

• Look for mold on underside of roof deck
• Check for frost on nails (winter moisture issue)
• Dark stains on plywood/OSB
• Wet or compressed insulation
• Visible air leakage from bathrooms or kitchen fans
• Soffits blocked by insulation (very common)
• Check if baffles are installed

9. Ventilation & Heat Imbalance Test

• Check if attic is excessively hot in summer
• Look for ridge vent, roof vents, or turbine vents
• Verify soffit vents are open and continuous
• Condensation evidence = inadequate ventilation

Poor ventilation drastically reduces roof lifespan.

10. Winter Performance Evaluation (Ontario-Specific)

• History of ice dams on the home
• Large icicles forming every winter
• Water stains near eaves (ice dam backflow)
• Snow sits unevenly on roof (indicates heat loss)
• Attic frost melt causing dripping in late winter

11. Structural Warning Signs

• Sagging roof deck visible from outside
• Uneven ridgeline when viewed from street
• Soft spots found inside attic
• Cracks in drywall corners below roof sections
• Sticking doors or shifting frames (possible structural movement)

12. Leak & Repair History Checklist

• Ask seller to disclose all previous leaks
• Request photos or invoices of repairs
• Check ceilings for past patch jobs
• Search for hidden water stains behind blinds/curtains

13. Negotiation Leverage Checklist

• Roof age older than 10–12 years (asphalt)
• Visible granule loss or bald patches
• Active or recent leaks
• Improper ventilation system
• Attic mold or moisture
• Structural sagging or soft spots

If any of these appear, you can negotiate:

• Price reduction
• Roof repair credit
• Full roof replacement credit