Deck & Pergola (Landscape) Install SWMS

Installing a timber or composite landscape deck and pergola structure is a multi-stage construction activity that combines ground excavation, structural carpentry, and elevated work. The scope typically covers footing pad or stump installation, bearer and joist framing, decking board fix-off, balustrade construction where the finished surface exceeds one metre above natural ground, and step or stair tread installation. Under WHS Regulation 2025, this work meets the definition of construction work and triggers multiple High Risk Construction Work categories listed in section 291, including work at heights where a person could fall more than two metres, structural work, and use of powered plant. A documented Safe Work Method Statement is mandatory under Regulation 309 before any work commences, must be prepared in consultation with affected workers under section 47 of the WHS Act, and must be readily accessible at the workplace. The SWMS controls manual handling injuries from heavy bearers, fall risk from elevated joist platforms, power tool lacerations, and silica exposure from concrete footing drilling.

Hazards identified

7 hazards covered, sorted by priority.

Control measures

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

1. 1Elimination — Specify pre-cut decking board lengths and pre-assembled balustrade panels from supplier to remove the majority of on-site power tool cutting and dust generation.
2. 2Elimination — Schedule footing excavation by licensed mini-excavator operator rather than hand auger to remove repetitive manual handling and silica drilling exposure entirely.
3. 3Substitution — Substitute hardwood bearers with lighter LVL engineered timber or aluminium subframe systems reducing per-piece weight below 20kg manual handling threshold.
4. 4Substitution — Replace petrol-driven concrete drills with low-vibration cordless rotary hammers fitted with M-class on-tool dust extraction for footing fixings.
5. 5Engineering — Install temporary edge protection guardrails compliant with AS/NZS 4994.1 along all exposed joist platform edges before any decking board fix-off commences above one metre.
6. 6Engineering — Use mechanical board-lifting jaws, bearer trolleys, and two-person carry straps for all subframe components exceeding 20kg single-person lift limit.
7. 7Administrative — Conduct Dial Before You Dig search and on-site cable locator scan before any footing excavation, with permit signed off by site supervisor and retained in project file.
8. 8Administrative — Implement daily pre-start toolbox talk referencing this SWMS, rotate cutting and fastening tasks every two hours, and enforce hydration breaks during BoM forecast above 32°C.
9. 9PPE — Mandatory P2 respirators during all concrete drilling and composite cutting, cut-resistant gloves rated EN388 Level 5 for board handling, and AS/NZS 1337 safety glasses.
10. 10PPE — Steel-capped boots to AS/NZS 2210.3, long-sleeve UPF50+ workwear, broad-brim hard hat, and hearing protection SLC80 Class 4 when operating circular saws and nail guns.

Applicable Codes of Practice

High-Risk Construction Work triggered

Worked example

A two-person landscaping crew arrives at a suburban residential site to install a 24-square-metre spotted gum deck with attached pergola, 1.4 metres above the sloping rear lawn. At the pre-start brief on the tailgate of the ute, the leading hand opens this SWMS on a tablet and walks the apprentice through each hazard line by line. They identify that footing depth has already been drilled by the excavator subcontractor, eliminating silica exposure for the day, and tick that control as not applicable. They confirm balustrade height triggers a high risk construction work category and erect temporary guardrail brackets onto the outermost joists before any board fix-off begins. The leading hand demonstrates the two-person carry strap for the 4.8-metre merbau bearers, referencing the manual handling control. Both workers sign the SWMS sign-on sheet and record their construction induction card numbers. Mid-morning, an unforecast 36°C heat spike arrives; the apprentice flags the administrative heat control clause, and they rotate to shaded pergola rafter assembly and extend smoko breaks. When a buried Telstra conduit is exposed near footing six, the leading hand stops work, photographs the strike, annotates the SWMS as a field amendment, and contacts the principal contractor before re-planning the final two footings by hand.

Related legislation

• WHS Act 2011 (model)
• WHS Regulation 2025
• Managing the Risk of Falls at Workplaces CoP

Frequently asked questions