For detailed information on process, pricing tiers, technical specifications, and FAQs, see our comprehensive loft conversions guide.
View Full Loft Conversions Guide →Central London's stucco townhouses, listed terraces, mansion flats, lateral apartments and lower-ground residences often hide the easiest extra square metres in the house: the roof. A well-planned loft conversion can add a principal suite, a guest room, a studio, or a work-from-home floor without sacrificing precious garden space.
What changes from street to street is the planning envelope. Across Central London, listed building consent, leasehold approvals, conservation controls and premium neighbour sensitivities all shape whether a dormer, mansard or rooflight scheme is viable. We factor those constraints in before drawings are fixed.
Our architects, structural engineers and build teams work across Marylebone, Mayfair, Belgravia, and Knightsbridge and the wider Central London market, coordinating staircase design, steelwork, fire strategy, drainage and final finishes under one contract.
Each loft type suits different roof shapes, budgets and planning contexts. We design and build all four — and advise honestly on which is right for your property.
The most popular London loft conversion. A flat-roofed box dormer extends from the rear roof slope, creating a full-height room with vertical walls and maximum usable floor area.
A near-vertical rear wall (72°) with a shallow set-back top slope. Creates the maximum internal volume and feels like a full additional storey. Common in period London properties.
Roof windows installed within the existing roof slope — no structural alteration to the roof profile. The most cost-effective option where existing headroom is sufficient (2.2m+ at ridge).
The hipped (sloping) side of the roof is extended vertically to create a gable wall, then combined with a rear dormer. Dramatically increases usable floor area on semi-detached and end-terrace homes.
A loft conversion is one of the most disruptive home improvement projects — which is why process, programme and communication matter as much as design quality.
We visit your property, climb into the loft and take precise measurements: ridge height, rafter pitch, purlin and collar positions, chimney breast locations, existing services routes and party wall conditions. We check whether your property falls within a conservation area or Article 4 direction, review the permitted development allowance, and assess the structural condition of the existing roof. You receive a written feasibility report, a recommended loft type and an indicative cost range within 48 hours.
Our architects produce the loft layout — optimising bedroom dimensions, en-suite position, staircase location (critical to minimising disruption to the floor below), window placement and storage integration. Structural engineers calculate the steel beam sizes, new floor joists and any required wall strengthening. We submit planning applications where required, building regulations drawings to the local authority and party wall notices to adjoining owners. Everything runs in parallel to compress the pre-construction timeline.
Scaffolding goes up, the existing roof is opened from the inside and temporary weatherproofing installed — your home stays watertight throughout. Steel beams are craned in and bolted into position, new floor joists laid, and the dormer or mansard structure built from the outside. The new roof is tiled or clad, windows installed and the shell made fully weathertight. This is the most intensive phase — typically three weeks — after which the remaining work is internal.
Insulation (meeting or exceeding Part L requirements), plasterboarding, first fix electrical and plumbing, underfloor heating (where specified), staircase installation, bathroom tiling and sanitary ware, second fix carpentry — skirting, architraves, door linings, built-in wardrobes — and full decoration. The staircase is typically installed in week 5, reconnecting the new loft level to the rest of the house.
We conduct a comprehensive internal snag inspection before inviting you to do the same. Every item is documented and resolved. Building control conducts their final inspection and issues the completion certificate. Scaffolding comes down, the site is cleared and we hand over your new loft with all warranties, certificates and maintenance guidance. Our 12-month defects liability period starts from this date.
Guide prices for London loft conversions in 2024. All prices are fixed-price and include design, structural engineering, building regulations and full build.
Roof windows only, no structural roof alterations. Ideal for studies, playrooms or extra bedrooms where existing headroom is adequate.
Full-width flat-roof dormer to the rear. Creates maximum floor area with full-height walls. Often under permitted development.
Side gable extension plus rear dormer. Ideal for hipped-roof properties, dramatically increasing loft volume and usable space.
Near-vertical rear wall creates a full-height additional storey. Requires planning permission. The premium option for terraced homes.
What makes a Hampstead Renovations loft conversion different from a standard loft company.
Every loft is designed by a RIBA chartered architect — not a salesperson with a CAD template. Your layout is optimised for your specific roof geometry, light conditions and lifestyle requirements.
Steel beam calculations, floor joist sizing and wall strengthening are designed by our own engineers — not outsourced. This eliminates coordination delays and ensures the structure is designed hand-in-hand with the architecture.
Your quotation is the final price — no provisional sums, no contingency allowances, no "we'll price that when we see it" clauses. If we underestimate, that's our problem. You know the total cost before signing.
We've secured loft approvals in Camden, Islington, Haringey and Westminster conservation areas where mansard and dormer policies are most restrictive.
RICS surveyors handle all party wall notices, schedules of condition and agreements in-house — avoiding third-party delays and additional professional fees.
The staircase is the single most critical design element in a loft conversion. We optimise position and geometry to minimise impact on the floor below while meeting Building Regulations.
We ensure full compliance with Part B fire regulations — fire doors, protected escape routes, mains-wired smoke detectors and, where required, sprinkler systems for three-storey conversions.
Most loft conversions include an en-suite. We design compact, high-quality bathrooms that work within roof slope constraints — including walk-in showers, wall-hung vanities and concealed cisterns.
Where planning permits, we can incorporate a Juliet balcony, roof terrace or balcony dormer into the loft design — adding outdoor space at roof level.
The eaves space either side of a dormer is wasted in most loft conversions. We design bespoke fitted wardrobes, drawers and storage units that exploit every centimetre of dead space.
Most of our loft conversions are completed while families remain in the property. We manage dust containment, access routes and noise scheduling to minimise disruption to daily life.
Selected loft conversions completed by our team across North and Central London.
Master bedroom with walk-in wardrobe and luxury en-suite. Full-width flat-roof dormer under permitted development, completed in 10 weeks.
Two-bedroom mansard with family bathroom, negotiated through Camden's conservation area mansard policy. Planning approved with heritage-sensitive design.
Combined hip-to-gable and rear dormer creating a master suite with separate home office and luxury en-suite on an Edwardian semi-detached.
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Visit Hampstead On Demand →The staircase design was brilliant — they found a way to position it without losing any space from the second bedroom. We were convinced it couldn't be done without sacrificing a room, but the architect solved it by rotating the flight direction. The loft itself is now the best room in the house.
We needed a mansard in a conservation area — three other companies told us it wouldn't get planning approval. Hampstead Renovations prepared a thorough application with proper heritage justification and it was approved first time. The build quality was exceptional and they finished a week early.
Fixed price meant fixed price — not a penny more. We lived in the house throughout the build with two young children and they were incredibly considerate about noise, access and keeping the house clean. The hip-to-gable added so much more space than we expected. Absolutely worth every penny.
Everything London homeowners ask about loft conversions — answered by our architects and engineers.
Use the area pages below to jump straight to the streets, councils and property types most relevant to your project.
Dormer, mansard and rooflight schemes for mansion flats, Georgian townhouses and medical-quarter apartments.
Dormer, mansard and rooflight schemes for premium apartments, lateral reconfigurations and heritage-led interiors.
Dormer, mansard and rooflight schemes for grand stucco houses, mews properties and basement-heavy schemes.
Dormer, mansard and rooflight schemes for luxury apartments, townhouses and high-spec fit-outs.
Dormer, mansard and rooflight schemes for listed terraces, institutional-grade approvals and complex party-wall contexts.
Dormer, mansard and rooflight schemes for stucco terraces, lower-ground homes and compact townhouse footprints.
Book a free consultation to discuss your central london project. We will assess feasibility, planning context, likely budget and the most efficient route from design to construction.
We measure your roof, assess feasibility and provide a fixed-price quotation — all at no cost and no obligation.
Book Free Loft SurveyGuide prices including VAT. Final costs depend on specification and site conditions.