Preliminaries: what to include in your prelims and how to stop giving them away
Ask ten builders what their prelims are and five will say "about ten percent". That is how prelims become the first thing to go when the price feels high, and why a job that looked profitable at the quote stage ends up break-even. Preliminaries are real costs with real invoices. Price them as a list and they stop being negotiable.
What preliminaries are
Everything it costs to run the site that is not a measured item of work: supervision, welfare, access, protection, plant, insurance and the paperwork. On a commercial tender they are a separate priced section. On a domestic quote they are usually hidden, which is the problem.
The checklist
Management and staff
- Site manager or working foreman time that is not productive labour
- Contracts manager and QS visits
- Health and safety: inductions, toolbox talks, the construction phase plan, RAMS
Site establishment
- Welfare: toilet hire, drying room, canteen, or an agreement to use the client's facilities
- Site office or container, storage container, secure compound
- Temporary fencing, hoarding, signage
- Temporary electrics and water, and the cost of the client's electricity and water
- Parking permits, pavement licences, road closures
Access and plant
- Scaffolding: erection, hire period, adaptations, inspections, dismantle
- Towers, ladders, MEWPs
- Telehandler or forklift, excavator hire, dumper, compactor, breakers
- Craneage for steels
- Small tools and consumables, usually a weekly allowance
Protection and cleaning
- Floor and stair protection, dust screens, polythene
- Protection of the client's belongings and the neighbour's property
- Daily clean, builder's clean at completion, sparkle clean
- Pest and weather protection to open structures
Waste
- Skips by size and number, or a grab lorry
- Hazardous waste: asbestos, plasterboard separation
- Waste transfer notes
Insurance and compliance
- Contract works insurance for the project value
- Any uplift to public liability for the job
- Building control fees where you are paying them
- Party wall costs where you have taken them on
- Testing and certification: electrical, gas, air tightness, sound tests
Time-related costs
- Everything above multiplied by the programme in weeks. A four-week overrun on a job with £900 a week of hire and supervision is £3,600 you did not price
How to price them
List each item with a quantity and a rate: scaffolding £2,400 fixed plus £180 per extra week, skips 6 at £320, welfare 12 weeks at £95, site manager 12 weeks at 1.5 days a week. Total it. On a domestic extension that comes to 8% to 15% of the works; on an occupied commercial refurbishment it can be 20% or more. When you see the list, you will not knock £4,000 off it to win the job, because you will see what the £4,000 is.
Show them or hide them?
On a domestic quote, show a line for "site set-up, welfare, scaffolding, skips and protection" with a sensible description. Clients understand that skips cost money. What they do not accept is a vague percentage. On commercial tenders, price the prelims section line by line as the bill asks, and make the time-related items explicit so an extension of time has a price attached.
Keep them honest on site
Prelims are the easiest costs to overrun because nobody measures them. Track scaffold weeks, skip counts and supervision time against what you priced. EstiMate's job costing puts the prelims allowance next to the actual spend as supplier invoices and hire come in, so a job that is drifting shows up in week three rather than at the final account. For the paperwork side, the construction phase plan and RAMS are produced from the job in minutes rather than priced as half a day of someone's time.
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