Loft Conversions · Sevenoaks
Loft conversions in Sevenoaks — designed, engineered and built by RCB.
Dormer, hip-to-gable, mansard and Velux loft conversions — full structural design, planning coordination and build. Trusted by homeowners across Sevenoaks and the wider Kent area.
Loft Conversions specialists serving Sevenoaks
RCB Design & Build is an FMB-accredited, TrustMark-endorsed principal contractor based at 347 Barking Road in East London. We deliver loft conversion projects across Sevenoaks and the surrounding Kent catchment — covering everything from initial feasibility through to final sign-off, under one contract, with one accountable team.
Sevenoaks is an affluent Kent market town set within the Greenbelt, with fast commuter services from Sevenoaks station reaching London Bridge in under 30 minutes. Large detached period homes, Arts and Crafts villas, and substantial Edwardian and Victorian properties — many on generous plots with mature gardens and outbuilding potential. That mix of housing styles is exactly the kind of stock our team has been working on for more than 20 years — we know what is structurally possible, what planning will actually approve, and where surprise costs typically appear.
Why Sevenoaks homeowners choose RCB for loft conversion projects
Most local builders we meet on rescue jobs share the same pattern: a low headline price, a partial scope, no proper structural engineering input, and stage payments that aren’t tied to defined deliverables. We do the opposite. Every project starts with a written scope, a fully costed schedule of works, a structural design from a qualified engineer, and a programme you can hold us to.
For loft conversion work in Sevenoaks specifically: Approx 50–60 minutes from our East London base via the A21 or M25 / A21. That short travel time means a senior member of our team is on site quickly when decisions need making, not booked in for the following week.
Indicative loft conversion costs in Sevenoaks
Pricing always depends on size, specification, structural complexity and condition of the existing property — but for genuine planning purposes, the ranges below are honest starting points.
From
£45,000
Typical range
£55,000–£85,000
Up to
£120,000
A simple rear-dormer loft conversion with a bedroom and en-suite typically sits in the £55,000–£85,000 range. Mansard conversions, full rear / L-shaped dormers and steel-heavy structural rebuilds run higher. Heritage and conservation work is priced individually.
Higher specification expectations and conservation-area requirements in the town centre push material costs above London average; we price heritage-sensitive work transparently. For a written, area-specific estimate based on your actual property and brief, the next step is a free project review.
What’s included in a loft conversion project with RCB
Working in Sevenoaks: what to expect from us
Our team operates across TN13, TN14 and the immediately surrounding postcodes including Otford, Dunton Green, Westerham, Riverhead. We handle parking permits, skip licences, party wall coordination and neighbour notification as part of the standard contract — those are project costs we own, not items you discover halfway through.
Where conservation-area, listed-building or Article 4 restrictions apply locally, we factor heritage compliance into the design from day one. Where the local council has known quirks — particular pre-app processes, validation requirements or favoured materials — we use them to your advantage rather than discover them after a refusal.
Frequently asked questions
How long does a loft conversion take from start to finish?
Most loft conversions complete on site in 8–12 weeks once design and approvals are in place. Pre-construction (design, planning, structural calcs) typically adds another 8–14 weeks depending on whether planning permission is required.
Do I need planning permission for a loft conversion?
Many loft conversions are possible under permitted development, but it depends on the property type, location, conservation status and proposed roof changes. We assess this at the survey stage and either submit a Lawful Development Certificate application or a full planning application.
Will my staircase need to move?
Not always. We assess existing staircase positions for headroom, escape compliance and how cleanly a new staircase can land in the loft. Where the existing layout works we keep it; where it does not, we re-plan.
Do I need to move out during the work?
In most cases no. Loft conversions are largely external until the very end, and we plan dust protection and staircase tie-in to minimise disruption.
Trusted. Accredited. Verified.
Independently vetted by the UK's leading construction accreditation bodies
FMB
Federation of Master Builders
TrustMark
Government Endorsed Quality
Checkatrade
Vetted & Reviewed
TrustATrader
Trusted Trader Listed
Planning a loft conversion in Sevenoaks?
Send us your address, your timeline and the basics of your idea. We will respond within one working day with an honest assessment, a sensible cost range and the next step that makes sense for your project.