Planning a roof replacement: seven checkpoints from survey to handover

Inspect timber, connections and substrate, not only visible sheets. Mark previous leaks and inaccessible areas. Base the repair allowance on survey findings and components that remain concealed.

Distinguish replacing a covering from changing roof geometry or converting an attic. Confirm requirements for this building with the designer and relevant authority. A neighbour’s project does not establish the position for a protected or differently constructed property.

Match structural requirements to interior use. Trapezoidal sheeting may suit a simple building, steel roof tiles a house, and roof sandwich panels a heated workshop. Check supports, pitch and joints for each option.

Select thermal and moisture-control layers with the covering. Include planned roof equipment before ordering: it needs load transfer and sealed penetrations. Unplanned openings through the completed roof create additional rework.

Order from measured slopes and a cutting schedule that includes laps and waste. Add flashings, ventilation, drainage and fixings. The building footprint gives neither the actual roof area nor a complete delivery list.

Agree package lengths, unloading equipment and suitable dry storage. Time delivery to the team’s readiness. Inspect packaging and edges on arrival, recording transport damage before installation begins.

Plan safe access, a waste area and emergency weather protection. Limit the area opened at once to what conditions and the team can protect. Do not rely solely on an optimistic forecast.

Do not damage or remove suspected asbestos roofing yourself. Arrange assessment and specialist handling with appropriate waste disposal. Retain records and reinspect the exposed structure before continuing.

Inspect timber repairs, substrate alignment and batten spacing. Photograph eaves, chimney and roof-window details before covering them. Check that water reaching the underlay has a designed drainage route.

When insulating, trace continuity of insulation and the internal airtight layer around services. Keep required ventilation paths open. Missing tape or junctions are easier to correct now than after lining the attic.

Follow the specific model’s instructions for laps and edge zones. Wind exposure may require different fixing patterns near edges. Handling and cutting must avoid bending sheets or damaging their coating.

Check flashing drainage before final fixing. Sealant cannot correct poor geometry. Remove swarf as work progresses and peel protective film within the period specified for the material.

Include gutters, roof-access equipment and penetrations in the final inspection. Record defects and agreed corrections. Collect product documents and photographs of areas that will be difficult to inspect later.

Keep instructions, warranties and purchase records with the maintenance plan. Check future installations against the existing assembly. The renovation’s durability also depends on later contractors preserving its protective layers.