The Beams team removed all the stress and matched me with a wonderful contractor."
Teresa
Queen's Park
On time and on budget. A real pleasure."
Eleanor
Stoke Newington
Completed our renovation project within budget and on time."
Evelyn
Bow East
London's loft conversion experts
We match London homeowners with vetted builders who specialise in loft conversions — and stay in your corner throughout the project.
One team, one contract
Your builder runs the project day to day — structure, staircase, electrics, plumbing, insulation and finishing — all under one fixed-price contract.
Design support available
Our designers can help you visualise the space in 3D before work begins. Your first design call is free.
Proper protections
Fixed-price contracts. Milestone payments held securely until you approve each stage. 12-month workmanship warranty from your builder.
Loft conversion gallery
Explore our completed projects.
Which type of loft conversion is right for your home?
Most London homes suit one or two conversion types depending on their roof shape, size and location.
Velux / rooflight conversion
The simplest option — Velux windows installed into the existing roof slope without changing the structure. Works well where existing head height is already generous.
Dormer loft conversion
The most popular choice for London terraced houses. A box-shaped extension added to the rear roof slope, creating full-height usable space. Can typically accommodate a bedroom and en suite.
L-shaped dormer
A rear dormer combined with a second dormer over the back addition — common in Victorian terraces with outriggers. Can add two bedrooms and a bathroom.
Hip-to-gable conversion
Suited to semi-detached and end-of-terrace homes with hipped roofs. The sloping hip is replaced with a vertical gable end, usually combined with a rear dormer for maximum space.
Mansard conversion
Maximum space. Near-vertical walls and a flat roof, creating an almost full-storey addition. Common in conservation areas and period properties. Almost always requires planning permission.
Is your loft suitable for conversion?
Most London lofts can be converted — but a few quick checks help set expectations.
Head height — you'll typically need at least 2.2 metres from floor joist to ridge.
Roof structure — older cut roofs (common in Victorian and Edwardian properties) are generally straightforward. Modern trussed roofs require more work but are still convertible.
Water tank — if your cold water tank is in the loft, it will need to be moved. Your builder factors this into the quote.
Roof pitch — steeper pitch means more usable space. Shallow-pitched roofs may need a dormer or structural change.
Not sure if your loft is suitable? A free estimate conversation is the quickest way to find out.
How much does a loft conversion cost in London?
Loft conversion costs in London typically run higher than the national average due to labour rates, access and the complexity of working in densely built Victorian and Edwardian streets.
As a guide, Velux conversions start from around £25,000–£45,000, dormers from £45,000–£75,000, hip-to-gable from £55,000–£75,000, and mansard conversions from £70,000–£100,000+. All figures are indicative ranges excluding VAT and professional fees.
For a full cost breakdown by type, see our guide to how much a loft conversion costs in the UK.
Do you need planning permission for a loft conversion?
Most loft conversions in London fall under Permitted Development rights — no planning permission needed — provided they meet size, height and materials criteria.
Exceptions include flats, properties in conservation areas, listed buildings, and mansard conversions. Building Regulations approval is always required. A Lawful Development Certificate is recommended for future sale.
The Party Wall Act 1996 applies if structural work affects a shared wall. Written notice must be served on neighbours at least two months before work begins.
For a full guide to planning permission and the Party Wall Act, see our blog on how to plan a loft conversion in the UK.
How a Beams loft conversion works
A clear process from first conversation to finished space.
Step 1 — Get your free estimate
Tell us about your home and what you're hoping to create. Your planner gives you a free estimate range before any commitment.
Step 2 — Design and plan
Work with a Beams designer to visualise the space in 3D — or work directly with your builder. Your first design call is free.
Step 3 — Built by your vetted builder
Your matched builder runs the project day to day — structure, staircase, insulation, electrics, plumbing and finishing. Milestone payments held securely until you approve each stage. 12-month workmanship warranty included.
Why a loft conversion beats moving house
A well-executed loft conversion in London typically adds 15–25% to your property's value — often significantly more where an additional bedroom and en suite are created.
Compare that to moving: stamp duty alone on a £750,000 London property is £27,500, and total moving costs regularly exceed £40,000 — before you've found somewhere bigger to buy.
Loft conversions across London
We work with vetted builders across all London postcodes — North London, South London, East London and West London.
Whether you're in a Victorian terrace in Hackney, a semi-detached in Wimbledon or an Edwardian property in Islington, our builders know the properties, the planning rules and the borough-specific quirks that come with London loft conversions.
Ready to start your loft conversion?
Get a free estimate and find out what's possible in your home. No commitment, no sales pressure.