The cost of fitting out an office can be staggering. And what looks like a fixed price on paper can quickly become something else entirely.
Many tenants underestimate the risk of fit-out cost overruns. They accept the lowest quote, only to find that the final bill is tens or even hundreds of thousands more than expected.
In some cases, costs have blown out by over 30% – all due to what are known as contractor’s variations.
What are contractor’s variations?
Variations are changes to the scope of works that are added during the construction process. These can stem from design issues, engineering oversights, or unexpected site conditions.
But not all variations are justified. Some contractors underquote upfront to win the job, then inflate the final cost through a series of seemingly “necessary” variations. This is where tenants get stung – and why proper contract structuring and oversight is essential.
Choose the right fit-out contract
The best protection against cost blowouts is a guaranteed lump sum design and construct contract.
This contract structure places all responsibility – design, engineering, project management, construction – on a single party. It locks in a fixed price for the entire project and makes the contractor accountable for delivering the fit-out within that price.
If they underestimate the cost, they absorb the loss. You don’t.
The only variations permitted under this model are those initiated by you – such as material upgrades or scope changes during construction. You’re not liable for surprises stemming from poor planning or errors on the contractor’s side.
Open book pricing & independent verification
Before signing a contract, your contractor should provide a detailed bill of quantities (BOQ). This document breaks down the fit-out into specific costed components – partitioning, glazing, painting, electrical, HVAC and more.
This process is known as open book pricing.
An independent quantity surveyor (QS) should then review this BOQ to ensure each item is accurately priced against market rates. the QS will issue a cost verification letter, confirming whether the contractor’s pricing is fair and reasonable.
This step isn’t just about getting a good deal. It’s about avoiding disputes later and ensuring your budget has a solid foundation.
Lock it in
Once the BOQ is verified, it should become the final scope of works – and the foundation of your fixed-price contract.
This combination – detailed scope, independent verification and lump-sum contract – gives you maximum cost certainty and ensures that the contractor, not you, carries the risk of overruns.
The role of the quantity surveyor
A quantity surveyor isn’t just there at the start. They act as your “construction policeman” throughout the project. They:
- Review and verify the contractor’s invoices (progress claims) to ensure they match the actual work completed.
- Visit the site to inspect works before approving payments.
- Audit the completed project to confirm it matches the agreed scope and quality.
This independent oversight protects you from inflated progress claims and ensures the contractor is held to account – from the first invoice to final handover.
Important: Never let the contractor appoint the QS. Choose your own and ideally work with a large firm that carries strong professional liability insurance.
Minimise risk, maximise certainty
Fit-out costs can sink a lease deal if they’re not controlled. The key to protecting your budget lies in:
- contracting under a guaranteed lump sum design and construct contract
- using open book pricing with a detailed bill of quantities
- engaging an independent quantity surveyor to verify, monitor and audit the project.
These steps shift risk away from you and onto the contractor – where it belongs.
When it comes to your office fit-out, cost blowouts aren’t inevitable. They’re preventable. But only if you build the right protections into your process.
