Built-Up Tar & Gravel Roofing SWMS

Built-up tar and gravel (BUR) roofing involves the hot application of bitumen at 200–260°C, alternating layers of reinforcing ply felts, and finishing with a mineral aggregate wear surface. The work combines molten hot works, LPG-fired kettles or tankers, heavy manual handling of felt rolls and gravel, and prolonged exposure at height on low-slope commercial roofs. Workers face catastrophic burn injuries from bitumen splash and kettle boil-overs, fatal falls from unprotected edges and skylights, respiratory exposure to bitumen fume containing polycyclic aromatic hydrocarbons, fire in the presence of insulation and combustible substrates, and heat stress from radiant loads on dark surfaces during summer.

Under the Work Health and Safety Regulation 2025 (NSW), this task is high risk construction work under section 291 — falls exceeding two metres, work in a contaminated or flammable atmosphere, and work in artificial extremes of temperature. Section 299 requires a Safe Work Method Statement be prepared before work commences, applied throughout, and kept accessible on site. Controls follow the hierarchy: eliminate exposure through pre-fabrication where feasible, engineer edge protection and fume-controlled kettles, and support with strict administrative burn-response and hot-works procedures.

Hazards identified

12 hazards covered, sorted by priority.

Control measures

Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.

1. 1Eliminate site hot works where possible by specifying torch-free self-adhered or cold-applied modified bitumen alternatives; retain BUR only where design or heritage requires it.
2. 2Substitute low-fuming Type III/IV bitumens with lower application temperatures and confirm operating range on the SDS; never exceed the flash point minus 25°C.
3. 3Install compliant perimeter guardrails, mid-rails and toeboards to AS/NZS 4994.1 before any material is landed on the roof; cover or rail all skylights and penetrations to withstand 1.1 kN.
4. 4Where guardrails are not reasonably practicable, deploy a fall-arrest system with anchorages certified to AS/NZS 5532 and full-body harness/lanyard to AS/NZS 1891.1; document a rescue plan with retrieval within 15 minutes.
5. 5Position LPG kettles at ground level with a 6 m exclusion zone from combustibles, on a level non-combustible base, fitted with a working thermostat, lid, and pressure/temperature gauges; hot bitumen is pumped or hoisted to the roof — never carried up ladders.
6. 6Implement a Hot Works Permit with a trained fire watch during and for 60 minutes after work; provide 9 kg dry-chemical and CO₂ extinguishers within 3 m of the kettle and mop cart, in accordance with AS 2444.
7. 7Engineer respiratory protection to AS/NZS 1715/1716 — minimum P2 with organic vapour cartridge for mop operators; position workers upwind and rotate to limit fume exposure.
8. 8Heat management plan aligned to the SafeWork NSW Managing the risks of working in heat guidance: reschedule to cooler hours where forecast exceeds 35°C, mandated hydration (250 mL every 20 min), shaded rest, and a documented buddy check for early heat illness signs.
9. 9PPE ensemble specific to BUR: heat-resistant leather gauntlets to elbow, bitumen-resistant boots laced tight with trousers outside boots (never tucked in), long cotton overalls, face shield with hard hat, and safety glasses to AS/NZS 1337.1 — no synthetic clothing which melts to skin.
10. 10Silica and asbestos controls: confirm substrate composition via a hazardous materials survey before removal of any pre-2004 roof; wet-sweep gravel and use an H-class vacuum to AS/NZS 60335.2.69 for cleanup; treat any suspect ACM under the Asbestos Code of Practice.
11. 11Burn first-aid station on site: minimum 20 L clean cool water for 20-minute irrigation, cling film dressings, and pre-arranged emergency route — nearest burns unit identified in the SWMS with GPS coordinates.
12. 12All workers hold CPCCWHS1001 (White Card) plus RIIWHS204E (work safely at heights); the SWMS is developed in consultation with workers under section 47 of the WHS Act, signed before work, and reviewed under section 302 on any incident, control failure or scope change.

Applicable Codes of Practice

High-Risk Construction Work triggered

Worked example

A commercial re-roofing contractor is engaged to strip and reinstate 2,400 m² of built-up tar and gravel roofing on a 1970s warehouse in Silverwater. The roof is 8.5 m above the loading yard and contains 14 fixed skylights and two mechanical plant penetrations. Before mobilisation, the contractor commissions a hazardous materials survey which identifies bitumen-bonded ACM flashings around the parapet — these are removed by a Class B licensed asbestos removalist under a separate SWMS. Perimeter guardrails to AS/NZS 4994.1 are erected and all skylights covered with load-rated mesh. A twin-burner LPG kettle is positioned in the yard within a bunded, non-combustible enclosure with a 6 m exclusion zone; bitumen is pumped through insulated hose to a roof-level dispensing cart. Mop operators wear P2 organic vapour respirators, full leather gauntlets and face shields. A Hot Works Permit is issued each morning with a dedicated fire watch retained for 60 minutes after final mop-off. During a January shift the forecast reaches 38°C — the heat plan triggers a 10:30 stand-down, work resuming at 15:00. The SWMS is signed by all seven workers, reviewed under section 302 after a minor bitumen splash to a worker's boot which was contained by correct PPE layering.

Related legislation

• Work Health and Safety Act 2011 (NSW) — sections 19, 31, 32, 47
• Work Health and Safety Regulation 2025 (NSW) — sections 291, 299, 302
• Work Health and Safety Regulation 2025 (NSW) — Part 4.4 Falls
• Work Health and Safety Regulation 2025 (NSW) — Part 4.1 Hazardous chemicals (bitumen, LPG, solvent primers)
• Work Health and Safety Regulation 2025 (NSW) — Chapter 8 Asbestos (where legacy ACM present)
• Environmental Planning and Assessment Act 1979 (NSW) — for demolition of ACM-containing roof elements

Frequently asked questions