What to check before repairing a roof

A roof leak is a symptom, not a complete diagnosis. Water can enter at one point, travel along timber, steel or underlay, and become visible somewhere else. Effective repair begins by checking the complete roof system and the conditions around it.

Record when and where the leak appears

Note whether water enters during wind-driven rain, long steady rain or immediately after a storm. Photograph ceiling stains and external roof areas safely from ground level. Do not climb a wet roof or improvise access.

Inspect the roof covering and junctions

Loose fasteners, punctured sheets, failed laps, cracked tiles and deteriorated sealants are common entry points. Flashings around walls, valleys, vents and parapets deserve particular attention because these junctions manage concentrated water flow.

Check drainage and roof geometry

Blocked gutters, undersized outlets and poorly directed downpipes can force water back into the building. Ponding may indicate inadequate falls or deformation. Repairing a visible hole will not solve a drainage problem that continues to overload the same area.

Assess the supporting structure

Look for corrosion, decayed timber, loose connections, sagging members and evidence of repeated wetting. Structural damage requires a properly defined repair rather than another surface patch. Ceiling boards and insulation may also retain moisture after the external leak is stopped.

Agree a repair scope

The scope should identify removal, replacement, fastening, flashing, waterproofing, gutter work and internal reinstatement. It should also explain what cannot be confirmed until damaged materials are opened. Request photographs of concealed conditions discovered during the work.

Prevent repeat failures

• Keep gutters and outlets clear
• Inspect penetrations and junctions periodically
• Replace incompatible or badly corroded fasteners
• Correct drainage defects instead of sealing around them
• Address wet ceilings only after the roof source is resolved