Estimate a UK renovation budget using project area, cost per square metre, fixed costs, professional fees, contingency and VAT.
This is a planning estimate, not a contractor quote. Scope, specification, access, structural work, location, permissions and discoveries during construction can materially change the final cost.
How to use the Home Renovation Cost Calculator UK
Enter the floor area being renovated and an estimated cost per square metre. Add fixed project items, professional fees, contingency and the VAT rate that applies to your quotes. Enter zero for any cost that does not apply.
How the renovation budget is calculated
| Budget item | Calculation |
|---|---|
| Area-based work | Renovation area × cost per m² |
| Base project cost | Area-based work + fixed project costs |
| Professional fees | Base project cost × fee percentage |
| Contingency | (Base cost + fees) × contingency percentage |
| VAT | (Base cost + fees + contingency) × VAT rate |
| Total budget | Base cost + fees + contingency + VAT |
Choose a realistic cost per square metre
The rate should reflect the planned specification and the work involved. Cosmetic updates usually cost less than projects involving structural alterations, plumbing, rewiring, bespoke joinery or major kitchen and bathroom work. Compare itemised local quotations rather than relying on one national average.
Allow for permissions and professional work
Some projects require planning permission, building regulations approval or both. GOV.UK states that major changes such as an extension may need planning permission. Check its planning permission guidance and the rules applying in your UK nation before work starts.
Related calculators
Estimate quantities with the Building Materials Calculator. Review future running costs with the Electricity Cost Calculator UK. Plan roof work using the Roofing Calculator. For qualifying non-domestic property, review the Business Rates Calculator UK. Browse more tools on the United Kingdom Calculator homepage.
Frequently asked questions
Does the estimate include VAT?
Yes, when you enter a VAT rate. Use the rate shown in your quotation or enter zero if VAT does not apply.
What should fixed project costs include?
They can include priced items not represented by the area rate, such as a kitchen package, bathroom suite, survey or specialist equipment.
Why add a contingency?
A contingency provides a budget allowance for unforeseen work, design changes and price movements. It is not a guarantee that overspending will be avoided.
Are professional fees always percentage-based?
No. Professionals may charge a percentage, fixed fee or hourly rate. Convert the expected amount into a percentage or include it in fixed costs.
Does every renovation need planning permission?
No. Requirements depend on the work, location and property. Planning permission and building regulations are separate checks.