Building Defect Severity Guide
Understand minor, major and structural defects — and what they cost to fix
Interactive Defect Reference For Buyers
Know What You Are Dealing With
Filter by severity to understand which defects are cosmetic maintenance items, which require professional rectification, and which demand urgent structural attention.
Surface Paint Cracking & Crazing
Hairline shrinkage cracking in paint or render, usually cosmetic and a normal result of thermal expansion.
Common Examples:
- •Paint checking on eaves
- •Hairline render cracks under 1mm
- •Efflorescence (white salt deposits on brickwork)
Typical Rectification Cost: $200 – $800
Minor Door & Window Adjustments
Doors or windows that stick slightly or require adjustment due to seasonal timber movement or minor settling.
Common Examples:
- •Door requiring a plane to close
- •Window latches misaligned
- •Sliding door off track
Typical Rectification Cost: $150 – $400
Gutter & Downpipe Maintenance
Gutters blocked with leaf litter, minor rust spots, or downpipes with small holes that have not yet caused water damage.
Common Examples:
- •Leaf-filled gutters
- •Pin-hole rust in downpipe
- •Missing gutter guard
Typical Rectification Cost: $200 – $600
Failed Shower Waterproofing
Shower membrane failure allowing water to saturate the wall framing and subfloor below, often concealed until significant rot is present.
Common Examples:
- •Drummy (hollow) shower tiles
- •Swollen skirting boards behind shower
- •Staining on ceiling below bathroom
Typical Rectification Cost: $3,500 – $9,000
Roof Tile / Sheet Failure
Cracked, slipped, or missing roof cladding allowing water ingress to roof space and ceiling linings, with potential mould growth.
Common Examples:
- •Broken terracotta tiles
- •Ridge capping loose or missing
- •Corroded metal roof sheets
Typical Rectification Cost: $2,500 – $12,000
Subfloor Stump Deterioration
Timber stumps supporting the floor frame have rotted due to moisture, insect attack or age, causing uneven and springy floors.
Common Examples:
- •Bouncy timber floors
- •Floors sloping more than 10mm over 3m
- •Visible stump rot in subfloor
Typical Rectification Cost: $4,000 – $20,000+
Significant Rising Damp
Moisture wicking upward through masonry walls due to a failed or absent damp-proof course, causing plaster damage, mould and salt.
Common Examples:
- •Peeling paint from skirting boards up
- •White salt deposits (efflorescence) inside
- •Mould along base of walls
Typical Rectification Cost: $5,000 – $18,000
Foundation Movement & Settlement
Structural movement of footings due to reactive clay soils, tree root activity, or inadequate design, causing significant cracking and distortion.
Common Examples:
- •Diagonal stepped cracks > 5mm
- •Doors and windows jammed shut
- •Visible gap between wall and ceiling
Typical Rectification Cost: $15,000 – $80,000+
Active Termite Infestation
Subterranean termites found actively damaging structural timber members in the subfloor, wall framing or roof space.
Common Examples:
- •Live termites in subfloor
- •Mud leads on stumps or external walls
- •Hollow-sounding skirting boards
Typical Rectification Cost: $8,000 – $50,000+ (treatment + repairs)
Roof Frame Structural Failure
Significant deterioration, overloading or removal of roof framing members, causing sagging, spreading or collapse risk.
Common Examples:
- •Visible sag in roof line
- •Fractured or missing rafters/purlins
- •Roof space supports removed for storage
Typical Rectification Cost: $12,000 – $45,000+
Found defects during your inspection? PrimeCheck provides clear severity-rated reports.
Frequently Asked Questions
What is the difference between a minor and major defect in a building report?
In Australian building inspection reports (aligned to AS 4349.1), a minor defect is cosmetic or maintenance-related and does not compromise structural integrity or safety. A major defect is significant enough to affect the structural performance, habitability, or safety of the building and typically requires professional rectification.
Do I have to fix all defects before I can buy a property?
No. As a buyer, identified defects give you negotiating power. You can request the vendor reduce the price by the estimated rectification cost, request the vendor repair defects before settlement, or walk away (if your contract contains a building inspection condition).
How does PrimeCheck classify defects in their reports?
PrimeCheck inspection reports categorise findings into Safety Hazards (urgent — requires immediate action), Major Defects (significant — professional rectification required), Minor Defects (maintenance — monitor or schedule repair), and Observations (informational — no immediate action required).