1. The headline figure is rarely the real number
UK homeowners usually budget for the builder's price and a vague idea of "finishes". The real cost of a renovation includes a long tail of smaller items that quietly add up to tens of thousands. Knowing what they are up front is the difference between a project that comes in on budget and one that doesn't.
2. Professional and statutory fees
- Architect or designer
- Structural engineer
- Planning application fees
- Building control fees
- Party wall surveyor
- Drainage surveys and CCTV
- Asbestos survey on older properties
3. Site logistics
- Skips and skip permits
- Grab lorries
- Scaffolding and licences
- Parking suspensions
- Site toilet for longer jobs
- Temporary power or water connections
4. Protection and making good
- Floor and stair protection
- Dust sheets and zip walls
- Making good driveways, lawns and fences
- Repainting rooms next to the works
5. Finishes that aren't in the builder's quote
- Kitchen units, worktops, appliances and installation
- Sanitaryware, taps, showers
- Tiles, grout, sealants
- Flooring and underlay
- Internal doors, handles, architrave
- Curtains, blinds, lighting
- Wardrobes and built-in storage
6. Services and IT
- Boiler upgrade or relocation
- Consumer unit upgrade
- Smoke and heat alarms to current regs
- Wi-Fi access points and data cabling
- EV charger
- External lighting and sockets
7. Living costs during the work
- Temporary kitchen setup
- Storage of furniture and belongings
- Possible short-term rental for major works
- Eating out and laundry
- Childcare logistics
8. Contingency, VAT and the things you can't see yet
Add VAT where applicable and a 10–15% contingency for variations, especially on older properties where you can't see what's behind the plaster. A contingency you don't use is a refund to yourself, not a waste.
Plan the real number, not just the builder's number
The Renovation Budget Planner includes a printable guide and editable spreadsheet covering every category above, with estimated vs actual tracking, payment schedule, variations and a cost-categories sheet. The free Builder Quote Checklist is a quick way to sanity check what's missing from a builder's headline figure.
Use this on your actual project
The free Builder Quote Checklist gives you a short printable pack to sanity-check any UK builder quote. The Renovation Budget Planner goes further with the exact ground covered in this article.
The Builder's Brief UK provides practical homeowner guidance based on real trade experience. It is not legal, financial, architectural, structural engineering, planning or building-control advice, and is not a replacement for project-specific guidance from suitably qualified professionals.