What a Renovation Really Costs (And Where the Money Goes)

Every renovation budget has three parts: the work you planned, the work you discovered, and the work you upgraded to halfway through. Only the first is ever in the spreadsheet.

Where the money actually goes

• Labour, typically 40-55%. More in cities, more on anything structural.
• Structure and envelope, 15-25%. Steels, roofing, windows. Invisible spending that adds no glamour and is entirely non-negotiable.
• Services, 10-15%. Rewires and replumbs are expensive and almost never optional in an older house.
• Kitchen and bathrooms, highly variable. This is where the range between sensible and extravagant is widest.
• Finishes. The part everyone plans in detail, and often the smallest slice.

The five decisions that move the number most

1. Moving services. Relocating a soil stack, a kitchen or a bathroom multiplies cost. Keeping wet rooms where they are is the cheapest big decision available.

2. Structural openings. Every steel needs a calculation, a supplier, padstones and often temporary support. Two openings cost far more than twice one.

3. Roof line changes. Dormers and raised ridges move a project into a different cost bracket entirely.

4. Bespoke joinery versus modified stock. A stock carcass with a bespoke door front captures most of the look for a fraction of the money.

5. Programme length. Every extra week is labour, hire, and often rent on somewhere else to live.

Contingency

• Post-1990 house, cosmetic work: 10%.
• 1930s to 1980s, some structural: 15%.
• Pre-1930, or anything with damp, movement or unknown wiring: 20-25%. Not optional.

Getting a quote you can trust

Give every contractor the same written scope, in the same order, with the same fittings specified. A quote that arrives as a single number is not a quote. Ask for it broken down by stage, ask what is excluded, and ask specifically about making good, waste removal and welfare.

The cheapest thing you can buy

Time spent deciding before work starts. Every change made after the first fix costs many multiples of the same decision made on paper.