Bungalow Loft Conversion Cost 2026: Prices, Types + Is It Worth It?

Prices last checked: 31 August 2026 · Page updated: 6 September 2026 · Prices researched from Checkatrade, MyJobQuote, FMB and loft specialists' 2026 guides

A bungalow loft conversion costs £30,000–£100,000 in 2026: a Velux conversion £25,000–£40,000, a rear dormer £30,000–£65,000, a hip-to-gable plus rear dormer £45,000–£80,000, and the raise-the-roof route £75,000–£150,000+. A bungalow conversion is not like a house conversion: the loft is bigger than any semi's, there is no staircase to build over, and the project effectively adds a whole storey. The defining trade-off is downstairs — the new stair takes a bedroom or a slice of the hall.

Home Renovation Guides' master bands sit in the loft conversion cost guide; this page covers the bungalow-specific numbers, the stair problem and whether the spend pays back. London adds 15–20% to everything below.

Bungalow loft conversion cost by type

The route follows the roof. Most UK bungalows are 1960s–70s hipped designs, which points at hip-to-gable; steep-pitch interwar chalet bungalows convert with a dormer or even Velux alone. MyJobQuote's 2026 bungalow guide quotes £30,000–£100,000 across all types, matching the combined range below.

Conversion typeTypical cost (UK, 2026)When it fits a bungalow
Velux / rooflight£25,000 – £40,000Steep 35°+ roof with 2.3m+ at the ridge — interwar chalet bungalows mainly
Rear dormer£30,000 – £65,000Gable-ended bungalows; adds full-height depth across the rear
Hip-to-gable + rear dormer£45,000 – £80,000The standard 1960s–70s hipped bungalow build; two bedrooms plus bathroom
Raise the roof / full storey£75,000 – £150,000+Shallow or low roofs where no conversion works; turns the bungalow into a two-storey house (MyJobQuote/Rated People 2026)

Per m², bungalow conversions run £1,000–£2,500, with dormer work at £1,150–£1,700/m² (MyJobQuote 2026). The floor plates are the largest in UK housing — 40–60m² is normal — so the same per-m² rate produces a bigger total than a terrace loft.

What fees does a bungalow loft conversion add?

The build quotes above sit alongside a fixed stack of professional fees, and bungalow projects carry two extras most houses skip: the staircase has nowhere to go without design work, and detached bungalows are the most common candidates for the craned modular route.

FeeTypical cost (2026)Notes
Architect / designer drawings£1,000 – £2,500Higher end for raise-the-roof designs needing planning drawings
Structural engineer£400 – £1,200Floor steels sized for long bungalow spans
Stairs and flooring£1,000 – £3,000Plus the ground-floor partition and making-good where the stair lands
Building control£500 – £1,0004–5 inspections to the completion certificate
Lawful Development Certificate£129Proof of permitted development for the sale file
Party wall surveyor£0 – £1,500Zero on a detached bungalow; one neighbour on a semi-detached bungalow
Trussed-rafter restructuring+£5,000 – £10,000Most post-1965 bungalows have fink or trussed roofs

Bungalow Loft Conversion Cost Calculator

Roof type, conversion route, finish and region for a 2026 range.

Where does the staircase go in a bungalow loft conversion?

The staircase goes through the hall in most bungalow conversions, and it always costs ground-floor space because there is no existing flight to stack above — the single biggest difference from a semi loft conversion. The three standard positions: over the corridor, with the landing feeding the new rooms; through a rear bedroom, which the house loses as a bedroom and regains upstairs; or against a living-room wall behind a new stud partition. Part K caps the pitch at 42° and sets 2m of headroom, so the stair run is 3–4m long whatever the layout, and Part B requires a protected enclosure with fire doors. Resolve the stair position in the first design week, because it decides the room layout on both floors.

Which bungalow roofs convert well?

Steep interwar roofs convert best. A 35–45° cut-timber roof on a 1920s–30s chalet bungalow gives 2.2m+ at the ridge and opens up with standard steels. The 1960s–70s stock is harder: hips on both ends, 25–30° pitches and trussed rafters. Those roofs take a hip-to-gable on one or both ends plus a rear dormer, with £5,000–£10,000 of truss restructuring (FMB). The head-height gate is 2.2m from the top of the ceiling joists to the ridge for a dormer design and 2.3m+ for Velux-only; a bungalow under 2.2m has one route left, which is raising the roof.

Bungalow roofEraConversion routeCost impact (2026)
Steep cut roof, 35–45°1920s–30s chaletVelux or rear dormerBaseline; easiest structure to steel
Hipped cut roof, 30–35°1930s–50sHip-to-gable + rear dormerBaseline plus the gable wall
Shallow trussed roof, 25–30°1960s–70sHip-to-gable + dormer after restructure, or raise the roof+£5,000 – £10,000 for steel and new rafters
Low ridge, under 2.2mAnyRaise the roof / full storey£75,000 – £150,000+ and full planning permission

Do you need planning permission for a loft conversion in a bungalow?

No for most bungalow loft conversions: rear dormers and hip-to-gables are permitted development under Class B within 50m³ of added volume for a detached bungalow — 40m³ for the rare terraced one — rear-facing only, no higher than the ridge, with materials similar to the existing house (Planning Portal). Two bungalow realities sit on top. First, raising the ridge or building a full storey always needs planning permission, and some councils protect single-storey street scenes by refusing visible dormers. Second, bungalows in conservation areas, Article 4 areas and on estates with permitted development rights removed by condition need an application regardless of design. Order a Lawful Development Certificate (£129) for every permitted-development build.

Is it worth doing a loft conversion on a bungalow?

Yes where the street supports the price. Nationwide's research puts the uplift from a double bedroom plus bathroom at around 20% of property value: roughly £70,000 on a £350,000 bungalow against a £45,000–£80,000 build. The bungalow-specific premium is the chalet effect — estate agents price bungalows with proper first floors above single-storey stock, because the buyer pool widens from downsizers to families. The honest subtraction is the staircase: losing a third bedroom downstairs to gain two up is a net win on paper and in the market, losing a second bedroom is marginal, and Home Renovation Guides' advice is to have a designer test the stair position before any quote is taken seriously. Moduloft's craned modular route, built off-site and lifted on in days, suits detached bungalows and cuts the on-site phase to about three weeks.

The raise-the-roof route changes the comparison. At £75,000–£150,000+ it competes with moving house, and the maths only works where the plot and location carry a two-storey value the bungalow cannot reach on its own — typical on tight urban plots and in the South East, weak where similar two-storey houses sell for less than the bungalow plus the build. A conversion that keeps the existing roofline is the lower-risk project in every region.

Can you do a loft conversion for 20k?

No. The cheapest bungalow route, a Velux conversion, starts at £25,000 and needs 2.3m+ of ridge height that bungalow roofs rarely offer. A £20,000 bungalow quote excludes the staircase (£1,000–£3,000), the floor structure or building control — or prices a shell with no fit-out. The genuine budget bungalow project is a Velux on an interwar chalet roof outside London at £25,000–£32,000.

What is the 10 year rule for loft conversion?

The 10 year rule makes a planning breach immune from enforcement 10 years after substantial completion: a previous owner's unpermitted bungalow conversion cannot be ordered removed after a decade. The paperwork gap remains, so buyers' solicitors ask for a Lawful Development Certificate for existing use (£129) or indemnity insurance (£20–£100). Building regulations breaches never expire — an uncertified stair or floor from any era must be rectified — and the rule is no basis for planning new work around the council.

Related loft conversion guides

Frequently asked questions

How much does a bungalow loft conversion cost?

£30,000–£100,000 in 2026: Velux £25k–£40k, rear dormer £30k–£65k, hip-to-gable plus dormer £45k–£80k, raise the roof £75k–£150k+. London +15–20%; trussed roofs +£5k–£10k.

Is it worth doing a loft conversion on a bungalow?

Yes where the market pays for the storey: ~20% value uplift (Nationwide), plus the chalet-bungalow premium. Weigh the ground-floor space the staircase takes.

Do you need planning permission for a loft conversion in a bungalow?

No for dormers and hip-to-gables within the 50m³ cap (detached bungalow). Raising the ridge always needs permission. Conservation areas and Article 4 are excluded from PD. Get an LDC (£129).

Where does the staircase go in a bungalow loft conversion?

Over the hall in most layouts, through a rear bedroom, or against a living-room wall. It must meet Part K (42° pitch, 2m headroom) and sit in a protected Part B enclosure.

Can you do a loft conversion for 20k?

No. A Velux starts at £25,000 and bungalow roofs rarely have the 2.3m+ it needs. A £20k quote is missing the stair, the floor structure or building control.

Which bungalow lofts cannot be converted?

Those under 2.2m to the ridge (raise-the-roof territory), and those in conservation areas or with PD rights removed until permission is granted. Trussed roofs convert at +£5k–£10k.

What is the 10 year rule for loft conversion?

Planning breaches become immune from enforcement 10 years after completion. Fix paperwork with an LDC for existing use (£129) or indemnity cover; building regulations breaches never expire.

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