Below-Ground Tanking & Basement Waterproofing SWMS
Below-ground tanking and basement waterproofing — excavated basement walls, raft slabs, and lift pits. Cementitious slurry, positive-side sheet membrane, drainage cell, and protection board.
SWMS variants reference your state’s WHS legislation. Instant download after payment.
Below-ground tanking and basement waterproofing is a high-risk construction activity involving the application of cementitious slurries, positive-side sheet membranes, drainage cell, and protection board to excavated basement walls, raft slabs, and lift pits. The work occurs in partially enclosed or fully confined spaces adjacent to unsupported or shored excavations, often in the presence of groundwater ingress, solvent-based primers, and gas-fired torches or hot-air welders. Under WHS Regulation 2025 Part 6.3, this activity is classified High Risk Construction Work because it is performed in or near a confined space, adjacent to excavation deeper than 1.5 m, and frequently involves the use of flammable substances in enclosed atmospheres. A documented Safe Work Method Statement is mandatory before work commences, must be developed in consultation with workers, kept accessible at the workplace, and reviewed if controls are revised or an incident occurs. Failure to prepare and implement a compliant SWMS exposes the PCBU, principal contractor, and supervising officers to enforceable WHS duties and category 1–3 offences.
Hazards identified
7 hazards covered, sorted by priority.
Loss of consciousness, asphyxiation, chemical pneumonitis, and delayed central nervous system depression requiring hospitalisation
Crush asphyxia, multi-system trauma, fatality, and prosecution under WHS Reg 2025 Part 6.3 excavation duties
Flash fire, deflagration in confined basement, severe partial-thickness burns, and structural fire spread
Acute lumbar disc herniation, crush injuries to lower limbs, falls from ladder, and chronic musculoskeletal disorder claims
Falls greater than 2 m causing fractures, head injury, spinal cord damage, and notifiable incident reporting
Allergic contact dermatitis, chrome ulceration, occupational asthma, and long-term sensitisation requiring medical removal
Fractures, lacerations, secondary fall into pit penetrations, and lost-time injury exceeding statutory thresholds
Control measures
Hierarchy-of-controls order: elimination → substitution → isolation → engineering → administrative → PPE.
- 1Elimination — Specify pre-applied bonded membrane systems installed on blinding before reinforcement and pour, eliminating downstream confined-space and excavation-edge application entirely where design permits.
- 2Elimination — Sequence works so basement tanking is completed before lift-pit shaft formwork and surrounding services restrict access, removing the confined-space entry requirement for follow-on coats.
- 3Substitution — Substitute solvent-based bituminous primers with water-based or low-VOC acrylic primers compliant with AS/NZS 4858 to remove flammable-vapour and narcotic-vapour exposure inside the basement envelope.
- 4Substitution — Replace cementitious slurries containing hexavalent chromium with reduced-chromate cements complying with EN 196-10 limits to eliminate Cr(VI) dermal sensitisation risk.
- 5Engineering — Install forced mechanical ventilation delivering minimum 20 air changes per hour into lift pits and tanked rooms, with continuous LEL, O2 and VOC monitoring per Confined Space CoP 2021.
- 6Engineering — Install temporary edge protection to raft slab perimeter and pit penetrations, certified shoring or battered excavation faces to AS 5047, and powered conveyor or hoist for membrane roll handling.
- 7Administrative — Issue confined-space entry permit, stand-by attendant with two-way comms, atmospheric test log, and SWMS sign-on at every shift pre-start brief; suspend works if LEL exceeds 5%.
- 8Administrative — Implement hot-work exclusion zone of 6 m from any solvent application, lock out torches and welders during priming, and rotate manual-handling teams every 30 minutes.
- 9PPE — Supplied-air respirators or full-face A2P2 cartridge respirators for primer application, nitrile chemical gauntlets, Type 5/6 coveralls, chemical-splash goggles, and AS/NZS 2210 safety boots with puncture-resistant midsoles.
- 10PPE — AS/NZS 1891 compliant full-body harness with dual lanyard and rescue retrieval system anchored above any confined-space entry, plus FR coveralls during any residual hot-work activity.
Applicable Codes of Practice
Mandates entry permit, atmospheric testing, stand-by attendant, and rescue plan whenever lift pits or tanked rooms meet the confined-space definition.
Requires shoring, benching or battering and a competent-person inspection where membrane crews work adjacent to excavations deeper than 1.5 m.
Defines product compliance, primer compatibility, and substrate preparation referenced by the SWMS when selecting membrane and solvent systems.
Governs subsoil drainage cell discharge, agricultural drain connection, and overflow paths integrated with positive-side tanking systems.
High-Risk Construction Work triggered
Membrane application inside lift pits and sealed basement rooms with restricted egress and accumulating solvent vapours meets the confined-space definition under WHS Reg 2025.
Positive-side tanking is applied against retaining walls of basement excavations and lift-pit shafts that routinely exceed 1.5 m depth before backfill.
Solvent-based primers and adhesives generate flammable VOC atmospheres inside the enclosed basement envelope during application and cure-off periods.
PCBU must prepare the SWMS in consultation with workers, keep it accessible on site, review after any incident or control change, and retain it for at least two years; penalties for non-compliance are substantial and indexed annually under the prevailing WHS schedule.
Who this is for
- →Specialist waterproofing subcontractors on basement projects
- →Principal contractors on multi-level residential basements
- →Civil contractors installing tanking to lift pits
- →Remedial waterproofers retrofitting below-ground structures
What you receive
- ✓Editable DOCX template — Microsoft Word compatible
- ✓State-specific WHS legislation schedule (NSW/VIC/QLD/SA/WA/TAS/NT/ACT)
- ✓Hazard register with risk ratings + hierarchy-of-control mapping
- ✓Worker sign-on register, pre-start checklist, and incident escalation flow
Worked example
On a four-level residential basement project, the waterproofing leading hand arrives at 6:30 am to apply solvent-primed sheet membrane to the lift-pit shaft and southern retaining wall. At the pre-start brief held at the site shed, the crew of three opens this SWMS on a tablet and walks the controls register line by line against today's conditions. The leading hand confirms the lift pit is 2.4 m deep with a single 600 mm access opening, triggering the confined-space entry permit (control 7) and forced ventilation set-up (control 5). The atmospheric monitor is calibrated and lowered; baseline O2 reads 20.9% and LEL 0%. Because the original specification called for solvent primer, the team substitutes the water-based primer already approved in control 3, eliminating the hot-work exclusion zone conflict with grinders running on level above. Each worker signs on against the SWMS, acknowledging the rescue retrieval anchor point and stand-by attendant rotation. Two hours in, the monitor alarms at 6% LEL from a neighbouring trade's adhesive — work is immediately suspended per control 7, the pit is purged, and the SWMS is annotated with the deviation and corrective action before re-entry. The signed document and atmospheric log are filed with the principal contractor at shift end.
Related legislation
- WHS Act 2011 (model)
- WHS Regulation 2025
- AS 2865 — Confined spaces