Physical feasibility
Head height, roof shape, roof structure and stair space are the biggest early signals of whether a habitable room is realistic.
Find out whether your loft is likely to convert, what type of conversion fits best, and the checks that matter before you speak to builders.
Best practice: ask only what changes the answer. The tool keeps technical questions simple and includes "not sure" options so people can still get a helpful result.
Head height, roof shape, roof structure and stair space are the biggest early signals of whether a habitable room is realistic.
The calculator flags flats, designated areas, front dormers and balconies because they are more likely to need planning permission or permitted development checks.
The result points users to the most relevant next action: cost estimate, planning check, or quote comparison with local specialists.
A loft usually becomes a realistic project when the space, structure, stairs and planning route all work together. The calculator weighs these signals, then points you to the checks that matter most.
A generous ridge height makes it easier to create a comfortable habitable room after the new floor, insulation and finishes are added.
Traditional cut roofs are often simpler. Trussed, low-pitch roofs or complex roofs can still work, but usually need more structural design.
A proper fixed staircase is one of the biggest feasibility checks, especially in smaller terraces where landing space is tight.
Conservation areas, flats and maisonettes, front dormers, balconies, chimneys and awkward services can all affect the best route forward.
The score is not a planning decision or a building-control sign-off. It is a quick way to understand whether your next step should be quotes, design advice, or a more cautious technical check.
Your loft has positive signals. The next useful step is usually a specialist survey to confirm measurements, stairs and structure before comparing quotes.
The project may still work, but at least one issue could affect the design, planning route or budget. Compare options in the loft conversion types guide before assuming a standard dormer will fit.
This does not mean impossible. It means you should validate head height, structure, ownership or planning risk before spending heavily on drawings or building regulations work.
These are the questions that stop a vague idea becoming an expensive surprise. They also make builder conversations sharper because you know what you need confirmed.
Sometimes, but low head height is one of the hardest feasibility issues. A specialist may look at dormers, lowering ceilings below, changing the roof structure, or deciding the project is better suited to storage rather than a habitable room.
No, but it usually makes the project more structural. Trussed roofs often need engineered support before the internal timbers can be altered, so costs and design complexity can be higher.
Yes. For a proper room, the loft needs safe fixed access. If there is no obvious place for stairs, the design may take space from a bedroom, landing or hallway below.
If your result flags planning risk, it is worth checking that early. Builders can still give guidance, but conservation areas, flats, front dormers and balconies can change the route significantly.