Research / Context statistics / Head office overhead as a share of the contract
Head office overhead as a share of the contract
1.98%of contract value
AustraliaLow confidenceContext
1.98% of contract value: Head office overhead as a share of the contract (O'Leary & Vaz-Serra, 2025; Australia; low confidence).
What it is. 1.98% of contract value, head office overhead.
Range 0.99% to 1.98% (scenario)
Sample. 30 senior Australian estimators, mostly building work.
What it is not. Our multiplication of two figures, one of them a UK 2002 number cited second-hand. Use your own rate if you have it.
Our arithmetic. Head office is 9.9% of preliminaries (table 4); preliminaries are 10% to 20% of the contract sum (introduction, citing Chan & Pasquire 2002). 9.9% x 10% = 0.99%; 9.9% x 20% = 1.98%.
Where it came from
- O'Leary & Vaz-Serra (2025), Challenges in pricing preliminaries costs for contractors: An Australian case studytable 4; introduction · source record