How much does it cost to renovate a house in London?

The reason the range is so wide is that 'renovation' covers two completely different jobs. One is cosmetic: decoration, flooring, a new kitchen and bathroom, keeping every wall and every pipe where it is. The other is a gut renovation: strip back to brick and joist, replace the wiring, plumbing and heating, move walls, and rebuild. The first is £300 to £700 per square metre. The second starts at £1,500 and goes past £3,500 for a high specification.

In Fulham specifically, most whole-house projects sit at the upper half of that range for two reasons. The stock is late Victorian, solid-walled and lath-and-plaster, so services cannot be run without chasing and making good — the plastering bill on a Victorian terrace is a genuine line item, not an afterthought. And the level of finish that suits a Fulham house, and that the resale market expects, is not builder-standard.

The figure that catches people out is the split between what you can see and what you cannot. Structural work, a full rewire, a new heating system and drainage typically account for 40 to 50 percent of a gut renovation budget, and every penny of it is invisible when the job is finished. Kitchens and bathrooms feel like the expensive part because you choose them from a showroom, but they are usually a smaller share than expected.

For budgeting, we would suggest working backwards from what you can spend rather than forwards from a wish list, and holding a 10 to 15 percent contingency that you genuinely expect to use. In a house built in the 1890s, something will be different from what the survey suggested — a failed lintel, an unexpected drain run, a chimney breast removed by a previous owner without support. A contingency is not pessimism, it is arithmetic.

More on this in costs & budgets, or see all 42 questions.