Fatigue Management on Residential Construction Sites

What it is

Fatigue is a state of physical or mental tiredness that reduces a worker's ability to perform tasks safely and effectively. Under section 19 of the model Work Health and Safety Act, the primary duty of care obliges a PCBU to eliminate or minimise risks to health and safety so far as is reasonably practicable. That duty includes the psychosocial and physical risks created by fatigue.

In September 2025 Safe Work Australia released a model Code of Practice on Managing the risk of fatigue at work. The code sets out how PCBUs are expected to manage fatigue under the model WHS Regulations, and it has been or is being adopted by every harmonised state and territory regulator.

Why fatigue matters on a residential build

Residential construction is a fatigue prone industry. Long shifts, early starts on summer trades, weather pressure, peak season scheduling, second jobs and commuting time stack on top of the physical load of trade work. The result is the same kind of impairment as alcohol intoxication.

Safe Work Australia reports that being awake for 17 hours produces a level of impairment broadly equivalent to a blood alcohol concentration of 0.05 per cent. A worker who started at 5 am and is still on site at 10 pm is, by that measure, intoxicated by tiredness alone.

What the model Code of Practice requires

The model Code is not law on its own. It becomes enforceable when a harmonised state or territory adopts it under its WHS Regulations. Once adopted, a court can use the Code as evidence of what a PCBU should reasonably have done. A failure to follow the Code is not an offence, but it makes the PCBU's position harder to defend.

The Code requires PCBUs to:

Identify fatigue risks

The PCBU must look at hours of work, shift design, mental and physical workload, the work environment, individual factors and travel to and from work. The risk identification is not done in a single fatigue policy. It is done at the level of each task and each roster.

Assess the risks

Assessment looks at the likelihood and consequence of fatigue impairing safety. A 12 hour day mixing concrete in 35 degree heat carries a different risk profile to a 12 hour day on internal painting in winter.

Implement controls

Controls are applied in the order of the hierarchy. Eliminate where possible, then substitute, then engineer, then administer, then PPE. For fatigue the early levels do the heavy lifting.

Review

The PCBU reviews controls after an incident, after a change in work and at planned intervals. Documented review evidence is what regulators look for.

Controls that work on a residential site

The model Code lists controls grouped by hours of work, shift design, workload, environment and individual factors. A subset of these apply directly to residential builders.

Hours of work

• Cap shifts at a defined length. Set a written rule that no worker exceeds 12 hours on site in a single day without an exception sign off.
• Define a minimum break between shifts. 10 hours between shifts is a common rule of thumb on civil and resource projects and is a reasonable starting point for residential.
• Restrict consecutive day rosters. Six on, one off is heavier than five on, two off across a quarter.

Shift design

• Avoid starting before sunrise where the task does not require it. Early starts shift workers' commute into low light, raising road risk.
• Schedule physically demanding tasks early in the day in summer and avoid them across the post-lunch low.

Workload and environment

• Plan adequate crew sizes. Solo trades doing two person tasks is a fatigue and an injury driver.
• Build realistic programmes. A weather pinched programme that forces double shifts is a fatigue programme.
• Provide shade, drinking water and rest areas on every site as a baseline.

Individual factors

• Talk to workers about second jobs, sleep and travel time. The conversation is the control.
• Provide a confidential route for a worker to report they are too tired to work safely.

Documenting the duty

A regulator looking at a fatigue incident asks three questions. Did you identify the risk. Did you put controls in place. Did you check they were working. Answering yes to all three needs records.

A short fatigue policy, a hours-of-work register that captures actual rather than rostered hours, induction content covering fatigue and a documented review after any near miss are the minimum evidence trail. A builder running ten residential sites with no fatigue paperwork is not unusual but is a weak position if an incident lands at a regulator's desk.

The standard the Code sets is reasonable rather than perfect. The builder who has thought about fatigue, written something down and acted on it is in a different category to the one who has never raised it on site.