Get a tailored estimate
Run the calculator with your postcode and project details for a regionally-adjusted indicative range in about a minute.
Open the calculatorMethodology
How Our Calculator Works
We use real-world data and regional price indices to build accurate home improvement estimates.
Already got a builder's quote?
Upload it and our AI Quote Checker flags overcharges, missing scope and the questions worth asking — line-by-line, in about thirty seconds.
Check my quoteCalculating the cost of a renovation is not an exact science—every home is unique, and unexpected issues can arise. However, by using a structured, data-driven approach, we provide you with a robust baseline estimate so you can budget efficiently. Here is a breakdown of our methodology.
1. Base Cost Algorithms
We maintain a proprietary database of base costs for different types of work (e.g., standard kitchen fitouts, new roof installations, wiring). These base costs are derived from analyzing industry quotes, material supplier lists, and recognized trade data in the UK.
2. Property Scope Adjustments
A 5-bedroom detached house costs considerably more to rewire than a 1-bedroom flat. Our calculator gathers basic configuration data from you upfront—property type, approximate size, and number of rooms—and dynamically scales the base quotes to fit your home's scope.
3. Regional Multipliers
Location dramatically affects labor costs and, to some extent, material delivery costs. We apply custom regional multipliers based on your postcode. For instance, jobs in Central London attract a premium compared to equivalent works in the North East or Wales.
4. Contingency Calculations
No project goes perfectly to plan. Our total estimates factor in a recommended contingency budget (usually 10-15%). This buffer protects you against hidden structural defects, minor specification upgrades, or delays that invariably crop up once you strip back the wallpaper.
The Importance of Formal Quotes
While we strive for high accuracy, it's vital to remember that our tool generates indicative estimates. It cannot see your existing pipework or assess whether your walls need re-plastering before the new kitchen goes in.
Always invite at least three reputable tradespeople to your property to provide formal, written quotations. Use our tool to sense-check those quotes and understand what is driving the price.
Get a tailored estimate
Run the calculator with your postcode and project details for a regionally-adjusted indicative range in about a minute.
Open the calculatorAlready got a builder's quote?
Upload it and our AI Quote Checker flags overcharges, missing scope and the questions worth asking — line-by-line, in about thirty seconds.
Check my quoteOr browse our renovation cost guides for project-by-project breakdowns.