Out-of-scope works: a UK subcontractor’s guide to pricing extras and getting paid

Every subcontractor knows the feeling. The general contractor (GC) pulls you aside at the end of the day and asks for one small extra. A duct rerouted. An extra fire-stop. A wall moved 300 mm. None of it was in the tender, and unless you price it and get it signed before the crew leaves, it quietly becomes a cost you absorb. With labour rates and material prices still climbing across the UK, those forgotten verbal extras routinely cost subcontractors £2,000 to £10,000 a job.

What counts as out-of-scope works

Out-of-scope works are any activities, materials or attendances the GC asks for that sit outside the contract documents, the priced bill of quantities or the agreed scope of works. Common examples on a UK site include:

• Structural or dimensional changes requested after the drawings are issued for construction
• Extra materials or finishes not in the specification or schedule of works
• Working outside the agreed programme, including overtime to suit the GC’s programme
• Making good or re-doing work caused by another trade, rather than your own defects
• Additional attendances, plant or access the GC assumes “comes free” with the package

A verbal instruction counts, if you can prove it

Under most UK subcontracts, a GC’s site instruction can trigger a variation even when it’s only given verbally. The Housing Grants, Construction and Regeneration Act 1996 and the Scheme for Construction Contracts back you up on that. But the law only helps if you can prove what was agreed. Do the work first and try to price it afterwards and you’ve already lost your best bargaining chip. The value has been delivered, the crew has gone home, and the GC’s commercial team has every incentive to argue the figure down.

“It’s not in the scope, so it’s not in the price. Get it signed before the truck leaves the gate.”

How to price extra work fairly (and quickly)

You do not need a full re-measurement to protect your margin. You need a defensible, transparent estimate the GC’s site manager can sign there and then. Base it on your real cost build-up:

1. 1Labour. The hours you actually expect, at your charge-out rate including overhead and burden.
2. 2Materials. What you’ll need, at cost, plus your usual margin.
3. 3Plant and access. Scaffold, hoist time or specialist kit the extra depends on.
4. 4Preliminaries. Supervision, small tools and the time your estimator spends pricing it.
5. 5Contingency. A small, stated allowance for what you can’t foresee.

Keep the estimate in hours and line items rather than a round number plucked from the air. A GC who can see your build-up will usually accept it. A mystery figure invites a fight, and a fight on site is the last thing you want mid-programme.

The paperwork that makes the price stick

A change order is only as strong as its evidence. When an extra is requested, capture four things in under two minutes:

• The job and location. Which project, which area, which drawing or level.
• The scope. A one-line note of what was asked for and why it sits outside the contract.
• Two photos. One wide shot for context, one close-up of the work.
• A signature. The GC’s site manager signs on screen to confirm the instruction and the agreed figure.

That signed record is your variation instruction. It goes straight to the office, becomes a formatted change order request and lands in the GC’s inbox and your billing team the same day. No more reconstructing “that job from March” from memory when the final account is negotiated.

What if the GC won’t sign on site?

If the site manager won’t sign there and then, you still have options. Confirm the instruction in writing the same day by email, mark it “to be priced at daywork rates” on your own record, and make sure your office knows before the work starts. An unsigned note on email is still worth far more than a pleasant memory of a conversation.

Why small extras become big losses

A single £400 extra is rarely the problem. On a busy site, extras get forgotten at a rate of one or two a week. Spread over a 40-week package that’s dozens of unbilled variations, and by the time the final account is settled you’re routinely looking at £2,000 to £10,000 in lost labour and materials on one job. The work itself wasn’t the cost. Forgetting to charge for it was.

Getting paid: the final-account mindset

When the final account is negotiated, the GC’s surveyor will only concede variations that are documented, priced and provable. A signed change order created on the day of the instruction is the strongest document you can put on the table. It beats an after-the-fact claim, and it beats having nothing at all. Build the habit on every site, not just the awkward ones, and your final accounts stop leaking.

Frequently asked questions

Out-of-scope work is part of the job. Unbilled out-of-scope work is a loss. Capture it, price it, get it signed, and the extras you already do start earning instead of leaking.