Preliminaries sense-check
Prelims (scaffolding, skips, welfare, supervision and site setup) are easy to under-price or hide. Enter what your quote shows and this tool will express them as a percentage of the job and compare them with commonly cited industry bands of about 8-14% for many domestic projects. Free, no sign-up, nothing leaves your device.
Last updated October 2026 · built by working UK builders
What should preliminaries cover?
Scaffolding, skips, welfare, protection, temporary services, permits, insurance, supervision and cleaning out. Full plain-English guide: what are preliminaries in a builder's quote?
About the 8-14% band
Quantity surveyors and published domestic cost guides often put prelims for many home projects somewhere around the high single digits to low teens as a percentage of the measured work, depending on duration and risk. It is a sense-check, not a rule. A short bathroom refit with no scaffold should sit lower; a tight urban site with road licences and a long programme can sit higher.
Got the full quote open? Run the quote checker or compare up to three quotes, then book a £59 review if prelims look odd.
Frequently asked questions
What are preliminaries in a builder's quote?
Prelims are the costs of setting up, running and clearing the site: scaffolding, skips, welfare, protection, temporary services, insurance, supervision and the final clean, rather than the building work itself.
What percentage should preliminaries be?
Published industry guidance for many domestic jobs often sits around 8-14% of the build cost, depending on programme, access and risk. Treat that as a sense-check only until firmed up against your quote.
What if preliminaries are missing from the quote?
They have not disappeared. Scaffold, skips and welfare still have to be paid for. Ask the builder to show them as lines or confirm they are inside other rates in writing.
Are low prelims a good sign?
Not always. Very low prelims can mean something is missing or the programme is unrealistic. Very high prelims need an explanation (difficult access, long programme, road licences).