Gutters every six months, the roof once a year, and after every big storm, as recommended practice; the roof anchors every twelve months as a requirement. No Australian standard fixes an inspection interval for a roof; AS/NZS 3500.3 governs how roof drainage is designed and installed and the owner's duty is to keep the building weatherproof and safe. The interval the industry and insurers work to is a six-monthly clean of all gutters, box gutters, parapet scuppers and downpipe inlets with the downpipes flushed through to the stormwater drain, quarterly under heavy trees or in the tropics and before and after the wet season in Queensland; an annual inspection of the cladding, flashings, penetrations, ridge caps and any membrane by a roofer; and an inspection immediately after a significant storm for displaced cladding, blocked drains and ponding. The roof anchor points and static lines the work is done from are inspected at intervals not exceeding twelve months under AS/NZS 1891.4.
The intervals
| Interval | What happens | Who |
|---|---|---|
| Six-monthly (quarterly under trees or in the tropics) | All gutters, box gutters, parapet scuppers and downpipe inlets cleared of leaf litter, sediment and debris; downpipes flushed and clear flow confirmed through to the stormwater drain; overflow scuppers confirmed unobstructed. In Queensland, before and after the wet season. | Competent person with working at heights training, or a roofing contractor |
| Annual | Roof cladding, flashings, penetrations (pipes, air conditioning units, skylights), ridge caps and gutters inspected for corrosion, displacement, cracking, lifting fixings or open joints; any membrane inspected for punctures, bubbling or lap joint failure. | Licensed roofer or competent person |
| After any significant storm | Immediate inspection for displaced cladding, blocked drains, water ponding and structural damage; photographs for the insurer. | Licensed roofer |
| Every twelve months (requirement) | Roof anchor points, static lines and other height safety anchorages inspected and tagged by a competent person under AS/NZS 1891.4; the anchors are not used if the tag is out of date. | Height safety inspector |
Who does it and what to keep
A roofing contractor for the annual and post-storm inspections and for repairs; a trained person with the right harness and a current anchor inspection for the gutter clean, or the roofer where access is difficult. Nobody goes on the roof without checking the anchor tags first. The record is the inspection report with photographs, the gutter clean dates, the anchor inspection certificate and tag date, and the repairs made, kept with the building's insurance file because a roof claim is paid or refused on the maintenance history.
The rule behind the interval
AS/NZS 3500.3 Plumbing and drainage, Part 3: Stormwater drainage, governs the design and installation of roof drainage, box gutters and overflow provisions; AS 1562.1 the installation of metal roof cladding. Neither sets an inspection interval; the six-monthly and annual routines are recommended practice under the owner's duty to maintain the building and the conditions of most property insurance policies. AS/NZS 1891.4 Industrial fall-arrest systems and devices, Part 4: Selection, use and maintenance, requires anchorages to be inspected at intervals not exceeding twelve months, and the work health and safety regulations require safe access for the work itself.
Common questions
Why are box gutters singled out?
A box gutter sits inside the roof line on a flat or low-pitched commercial roof. When it blocks, the water has nowhere to go but onto the roof, and ponded water is a live load the structure may not have been designed for. Roofs have collapsed for that reason, which is why the overflow scuppers must never be blocked and the box gutters are cleaned first.
Can our own staff clean the gutters?
Only with working at heights training, a harness on an anchor that carries a current inspection tag, and a second person present. On most commercial roofs that means a contractor. The anchor inspection is the twelve-monthly requirement that makes the rest possible.
Put it in the register
An interval only holds when the asset is listed with its tasks, its contractor and where the record lives. Standara's library carries this asset with the tasks above attached, so adding it to a site's register produces the year's schedule, the monthly to-do list and the completion record the auditor or insurer asks for. The fuller picture, with the neighbouring assets and the rule behind each interval, is in the facilities asset register guide.
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- A worked example: one club's register, planner and records for a year
- All guides and answers