Planning a Sensible Budget for Home Renovation Work

Begin with the number you would rather not see

Every renovation starts with a lovely idea and a slightly optimistic figure scribbled in the back of a notebook. Before you commit to anything, build a realistic budget from the bottom up rather than from the top down. That means pricing the work you actually need, not the work you would like to photograph. In UK homes, labour is usually the largest line item — a good joiner, plasterer or electrician costs money, and a small alcove or a tight hallway takes just as long to work in as a large, empty room. Awkward access, narrow stairs and period detailing all slow a job down, and slow jobs cost more.

Write three lists: essential structural and safety work, essential cosmetic work, and the nice-to-haves. Fund the first, budget properly for the second, and treat the third as the first thing to cut when the numbers wobble.

Contingency is not optional

If you take one thing from this article, make it this: the contingency fund is a cost, not a leftover. For a straightforward modern property in reasonable order, allow 10 per cent of the build cost. For a period home — Victorian terrace, Georgian townhouse, anything with lath and plaster, old pipework or a chimney breast you plan to open up — allow 15 to 20 per cent.

Where does contingency go? Almost always somewhere invisible:

• Rotten joist ends discovered under floorboards, or timber that has been quietly damp for decades.
• Hidden damp behind plasterboard, failed damp-proof courses, or a chimney breast that needs ventilating rather than simply sealing.
• Outdated wiring that fails to meet current regulations once walls are opened.
• Asbestos in older floor tiles, artex or boiler flues, requiring licensed removal.
• Uneven walls and floors that mean extra plastering, packing or levelling before anything can be fitted.

Keep that money in a separate account and do not spend it on a new sofa in week two. If the contingency survives to the end of the project, you have earned a very pleasant surprise.

Professional fees and permissions

These are the costs that catch people out because they arrive before any dust does. Budget for them separately from the building work.

• Structural engineer: typically £500 to £1,200 for domestic work such as removing a wall or opening up a chimney breast, plus any follow-up site visits.
• Planning application: householder applications in England are charged per application, and fees rise periodically — check the current figure on your local authority's website. Scotland, Wales and Northern Ireland differ.
• Building regulations: separate from planning permission, and required for most structural, electrical and glazing work.
• Party wall agreements: if you share a wall with neighbours, expect several hundred pounds per surveyor, and you may need to appoint one for each side.
• Drawings and design: even a modest alcove joinery scheme benefits from measured drawings, which can save expensive on-site guesswork.

Add VAT at 20 per cent to anything from a VAT-registered trade, and remember that some domestic energy-saving work is charged at a reduced rate — worth asking about rather than assuming.

Materials, lead times and price movement

Building materials do not hold still. Timber, steel, sheet goods and imported tiles have all shown sharp movements in recent years, and quotes are often valid for only 30 days. If your project runs over several months, assume a rise rather than a fall.

Where you can, buy the fixed items early — tiles, sanitaryware, handles, paint — and store them safely. This locks in the price and, just as importantly, protects your schedule. A joiner cannot fit alcove shelving around a radiator that has not arrived. Ask suppliers about lead times in writing, and add a week of slack for anything made to order.

Budgeting for period homes and alcoves

Period properties are wonderful and unforgiving. Lath and plaster walls are rarely straight, and an alcove that looks square is almost never square. Fitted alcove cabinetry has to be scribed to the wall, which takes skill and time, and that is reflected in the price. Expect a realistic figure for decent bespoke alcove joinery, painted and installed, rather than the cheap online estimate you saw once.

Set aside money for the supporting trades too: making good plaster, repairing cornice or picture rail, and refurbishing sash windows, which often costs several hundred pounds per window when cords, putty and draught-proofing are done properly. In small flats and narrow terraces, also budget for protection — dust sheets, temporary kitchens, storage for furniture while rooms are out of action, and possibly a short stay elsewhere.

Track it weekly and phase it sensibly

Keep a simple spreadsheet with three columns: quoted, invoiced and paid. Compare it against your budget every week, not every month. Ask for staged payments tied to completed work rather than large sums upfront, and never pay in cash without a receipt.

If the money runs short, phase the work rather than compromising on the parts you cannot redo — structural work, electrics, plumbing and waterproofing. Alcove shelving, paint colours and styling can all wait. A well-planned budget is not about spending less; it is about knowing what you are spending, so the finished home feels like a pleasure rather than a debt.