Having the Beams team on hand to manage the project and provide extra reassurance on build decisions was incredibly helpful and made the whole experience stress free.
Kerry
London
They have been extremely efficient and reassuring. It was a complex project but they took it all in their stride. They recommended very good contractors who were all punctual, polite and capable.
Andrew
London
All about trust. I felt comfortable with my money, my project, and my home knowing that the outcome would be to my satisfaction or would be made good.
Chris
London
Loft conversion experts in Westminster
Westminster's building stock ranges from grand Victorian and Edwardian mansion blocks in Marylebone and Maida Vale to the classic period terraces of Pimlico, each with different structural quirks that affect how a loft can be converted. Mansion block roofs are often shared with neighbouring flats and may involve leasehold and freeholder consents, while terraced houses typically have simpler party wall arrangements but narrower floor plates to work with.
Beams matches you with vetted loft conversion specialists who understand these differences and have worked on similar properties across the borough. That local knowledge means fewer surprises during survey and design, and a smoother path through planning and building control.
Types of loft conversion
There are several ways to convert a loft, and the right option depends on your roof type, the space available, and what you want to use the room for.
Velux or rooflight conversion: the simplest option, adding roof windows without changing the shape of the roof. Usually the most straightforward from a planning perspective.
Dormer conversion: extends the roof outwards to create a box-shaped structure, adding significant head height and floor space.
Hip-to-gable conversion: extends a sloping hip roof out to a vertical gable end wall, common on semi-detached and detached properties and increasing usable space substantially.
Mansard conversion: replaces one or both roof slopes with a near-vertical wall and flat roof, maximising space and often used on period properties with steep existing roofs.
Is your Westminster loft suitable?
Whether a loft can be converted depends on factors including the pitch and structure of the existing roof, the available head height, and the layout of the floor below. In Westminster's period terraces and mansion blocks, party wall matters are common considerations, since many properties share walls or roof structures with neighbours, and mansion block conversions may also need consent from a freeholder or management company. A qualified surveyor can assess your specific property and confirm whether conversion is feasible before design work begins.
What a loft conversion costs in Westminster
Costs for a loft conversion vary depending on the type of conversion, the size and structure of the roof, and the finish you choose. Westminster is one of London's premium property markets, so material and labour costs, along with the more complex party wall and planning requirements common in the borough, often push project costs toward the higher end of typical London ranges. The figures below are general estimates to help with budgeting, not fixed quotes; get a free estimate for pricing specific to your property.
Project scope | Estimated cost range |
|---|---|
Velux or rooflight conversion | £30,000 - £45,000 |
Dormer conversion | £45,000 - £65,000 |
Hip-to-gable conversion | £55,000 - £75,000 |
Mansard conversion | £65,000 - £90,000 |
Planning permission for loft conversions in Westminster
Westminster City Council has designated 56 conservation areas covering much of the borough, and some streets and areas within these carry an Article 4 Direction, which removes certain permitted development rights. As a result, loft conversions in Westminster more often require full planning permission than in many other London boroughs, particularly where the work would alter the roofline, add dormer windows, or be visible from the street. Even loft conversions that would normally fall under permitted development elsewhere may need an application here. It's worth checking the planning status of your specific property and its conservation area designation before finalising your design, as this affects both the design options available and the project timeline.
How a Beams loft conversion works
Getting started with Beams is straightforward, whatever type of loft conversion you're planning.
1. Free estimate and design call: tell us about your loft and get an initial estimate, along with a no-cost call to talk through your options.
2. Matched with vetted builders: we introduce you to up to three vetted loft conversion specialists, so you can compare like-for-like quotes.
3. Fixed price and protections: once you choose a builder, we put a fixed-price contract and milestone payments in place before work begins, with your workmanship covered for 12 months.
Why a loft conversion beats moving
Moving house comes with stamp duty, estate agent fees, and the disruption of finding a new home, on top of the emotional cost of leaving a neighbourhood you know. A loft conversion lets you add the space you need, whether that's a bedroom, home office, or bathroom, while staying in the area and the home you already have. For many Westminster homeowners, remaining close to local schools, transport links, and amenities is just as valuable as the extra square footage itself.
Converting a loft in Westminster
The average house price in Westminster stood at £877,000 as of July 2026 (ONS/HM Land Registry, provisional), reflecting the borough's position as one of London's most sought-after areas to live. With so much of the housing stock made up of period terraces and Victorian and Edwardian mansion blocks, many set within one of Westminster's 56 conservation areas, a loft conversion is often one of the few ways homeowners can add meaningful space without altering a building's protected character or moving away from the area altogether.
Other services in Westminster
We also help Westminster homeowners with:
If you need trusted trades for smaller jobs or ongoing work, our Builders in Westminster service matches you with vetted general contractors for repairs, refurbishments and more.
Looking to reimagine your interiors once the building work is done? Our Interior design in Westminster service pairs you with designers who can pull the whole scheme together.
If you need more space across the whole property rather than just the roof, our House extensions in Westminster service covers side return, rear and wrap-around extensions.
For homes where digging down makes more sense than building up, our Basement conversion in Westminster service covers full basement conversions and light-well additions.
Planning a wider refurbishment rather than a single room? Our Home renovation in Westminster service covers whole-house projects from planning through to completion.
If your bathroom needs updating alongside your loft project, our Bathroom renovation in Westminster service covers everything from a simple refit to a full redesign.
For a new kitchen to match the rest of your renovation, our Kitchen renovation in Westminster service matches you with vetted kitchen specialists.
Loft conversion in nearby areas
We also work on loft conversions in Loft conversion in Hammersmith and Loft conversion in Fulham.
Ready to start your Westminster loft conversion?
Get a free estimate and take the first step. No commitment, no sales pressure.