A loft conversion in Maidstone often succeeds or fails on the staircase. The stair needs headroom, a clear route and a safe landing. Costs for the whole project typically run from £25,000–£40,000 for a roof-light conversion to £45,000–£65,000 for a dormer, and South East work typically costs 15–25% more.
Loft conversions in Maidstone start with the stair
Plan the stair first, because it takes space from the floor below. Stairs have a maximum pitch of 42°, with 2.0 m headroom as standard. Where there is not enough space, a loft conversion may have 1.9 m of headroom at the centre of the stair, reducing to 1.8 m at the side. Therefore, a few centimetres can change the whole layout.
Our guide to loft conversion staircase ideas shows how owners fit stairs into tight hallways. For the engineering side, see our page on dormer loft conversions, where the stair and the structure are planned together.
Space-saver stairs and ladders
Building rules allow an alternating-tread stair only in a loft conversion. You can use one only where there is not enough space for a conventional stair. It may reach just one habitable room, plus a bathroom or WC if you want one. It cannot serve the only WC in the home.
A fixed ladder is even more limited. The rules permit one only for a loft with one habitable room and no space for a stair. As a result, most families need a conventional stair. It is safer, and it suits a bedroom.
Dormer or roof-light?
A dormer adds a box to the roof for more head height and floor area. It typically costs £45,000–£65,000 and typically takes 6–10 weeks on site. A rear dormer can fall within permitted development if it meets the limits. Front dormers need planning permission.
A roof-light conversion is simpler. The roof shape stays, and roof windows bring light in.
It typically costs £25,000–£40,000 and typically takes 6–8 weeks. However, it needs enough head height to begin with. Our page on roof-light loft conversions explains when it works.
Planning in Maidstone
Maidstone Borough Council is the local planning authority. England’s rules allow up to 40 cubic metres for a terraced house and 50 cubic metres for any other house. However, roof lights may not stand more than 15 cm proud of the original roof slope. Materials should look like the existing house.
The council lists 41 conservation areas. Permitted development does not apply in those areas. Similarly, a council can remove rights with an Article 4 direction. A Lawful Development Certificate costs £274 in England from 1 April 2026 and is decided within 8 weeks.
Kent costs and fees
The South East premium is typically 15–25% more than elsewhere in the UK. That is a guide, not a Maidstone price, so compare several quotes. For a quick check, roughly £1,250–£2,500 per m² is a common range across the UK.
Fees add to the total. Typically, drawings cost £1,500–£4,000. A structural engineer costs £750–£2,500, and Building Regulations cost £600–£1,500. Ask your adviser which of these are included in a quote.
Before you commit
Good preparation saves money. Our overview of loft conversions lists every stage. For example, measure head height, check the roof structure and think about the stair.
Talk to neighbours as well, particularly if you share a wall. A calm chat early avoids stress later, and it costs nothing. Our list of things to consider before a loft conversion covers each step.
Building Regulations approval is needed whether or not you need planning permission. Without approval you will lack the certificates you may need when you sell. Inspectors visit the site, and then they issue a completion certificate.
A realistic timeline
Design and approvals typically take 2–4 months before building starts. Then the dormer typically takes 6–10 weeks on site. Because of this, allow typically 4–9 months from first enquiry to a finished loft. Spring starts are popular, so book early.
Allow extra time if the council asks for changes to your drawings, since a revised plan restarts part of the review.
Nearby areas we cover
Owners across Kent and Sussex can also read about loft conversions in London, loft conversions in Brighton and Hove and loft conversions in Guildford. Each place has its own council, so check local rules.
Get started
Tell us about your house, your stair options and the room you want. We will help you pick a design that fits. Send your details through our contact form to begin.
