Typical 2026 prices for every type of loft, the fees most quotes leave out, and what pushes the price up or down.
Most loft conversions outside London cost between £30,000 and £75,000 in 2026. Where yours lands depends on the type of conversion, the size, the shape of your roof and the finish you choose.
The figures below are typical ranges drawn from industry price guides for a standard sized loft on a semi or terrace outside London, before VAT. Birmingham and the West Midlands usually sit in the lower half of each range. Treat them as a planning guide, not a quote. For a figure built around your own house, try our cost calculator or book a free survey.
Rooflights fitted into the existing slopes with no change to the roof shape. Cheapest and quickest, but only works where there is enough head height already.
A box dormer across the back gives full headroom for a bedroom and shower room. The most common conversion in the UK.
For semis and detached houses with a sloping side roof. The hip is built up into a gable wall, usually with a rear dormer as well.
Two dormers joined over the main roof and the back addition of a Victorian terrace. Often fits two bedrooms.
The rear slope rebuilt almost vertical for the most space. Nearly always needs full planning permission.
Drawings and structural calculations. Plans for building control typically cost a few hundred to a couple of thousand pounds, and a structural engineer usually charges £600 to £1,800 for the beam and joist calculations.
Building regulations. Every loft needs approval. Expect roughly £850 to £1,350 for the application and inspections, depending on whether you use the council or a private approver.
Planning or a Lawful Development Certificate. Most lofts are permitted development, but a certificate confirming it costs half the householder planning fee. A full householder application currently costs a little over £500 in England; check the Planning Portal for the latest figure.
Party wall. If you share a wall, your neighbours must be served notice. If they appoint surveyors, budget £1,000 to £2,500 per neighbour.
VAT and contingency. Check whether a quote includes VAT at 20 percent, and keep 10 to 15 percent back for surprises found when the roof is opened up.
A rooflight conversion, because the roof shape does not change. It only works if your loft already has enough head height, usually around 2.2 metres or more at the ridge.
In most areas a well built loft bedroom with a shower room adds more to the value of a house than it costs, which is why it is one of the most popular home improvements in the UK. Ask a local estate agent for figures for your street.
Usually 6 to 10 weeks on site, plus a few weeks beforehand for drawings, building control and any party wall notices.
Quotes differ in what they include. Some leave out the staircase, the electrics, decorating, building control fees or VAT. Ask for an itemised quote and compare line by line.
No. Our survey and written quote are free, and we never take money up front.
Tell us what you have in mind and we will book a free visit. Your itemised quote comes back within 3 to 5 working days.