We design, plan and build house extensions across Raynes Park and the wider Merton borough — one team, one fixed price, one project manager from sketch to handover.
Typical scope +18 to +60m²
Cost guide From £2,500 / m²
Build time 12–22 weeks
Consult Free 1–2 hour visit
BUILDING IN RAYNES PARK
Raynes Park's Victorian terraces and 1930s semis extend well — rear kitchens, hip-to-gable lofts, wraparounds. Our recent work nearby includes a completed loft conversion in Worcester Park; the same team designs, prices and builds every SW20 project end to end.
Side-return and rear kitchen extensions are very popular here, especially on narrow plots. Two-storey wrap-around projects add bedrooms and living space in one go.
Local advantage
Why homeowners in Raynes Park choose Dali Pro Services for house extensions
01 · PLANNING HANDLED
Permitted development or full planning — we tell you which on the first visit.
Many single-storey rear and side-return extensions in Raynes Park fall under permitted development; double-storey and wrap-around schemes usually need a full application to Merton Council. In streets of terraces and semis, party-wall notices to one or both neighbours are the norm — we serve and manage those ourselves. Our own team prepares the drawings and submits the application — one point of contact owns both the approvals and the build.
02 · ONE TEAM
Steels, thresholds and the kitchen — one team owns every junction.
An extension lives or dies where old meets new: the steel opening, the level threshold to the garden, the drainage runs, the kitchen that anchors the space. Our architects, structural engineers and site team sit in the same office, so nothing is lost between a designer’s drawing and a builder’s interpretation.
03 · TRANSPARENT PRICING
From £2,500 / m² — itemised and fixed.
Your quotation is broken down line by line — groundworks, shell, glazing, fit-out — and fixed against the agreed drawings. You pay in stages, only after each stage is signed off; variations only happen when scope genuinely changes, through written authorisation.
Recent local builds
House extensions we have completed near Raynes Park
House extensions in Raynes Park — frequent questions
Do you do house extensions in Raynes Park?
Yes — Raynes Park (SW20) is well within our Merton working area. We deliver several house extension projects across this borough each year.
How long does a house extension project take in Raynes Park?
On site, the build phase is typically 12–22 weeks. Add time up front for design, planning approval and structural sign-off — we give you a firm end-to-end programme with the fixed quote after the free site visit.
What does a house extension cost in Raynes Park?
Typical range: From £2,500 / m². Our online calculator gives you a tighter figure based on your house type and ambitions; the fixed quote follows a free site visit.
Will I need planning permission in Raynes Park?
It depends on the property. Many house extensions fall under permitted development; where a full application to Merton Council is needed (conservation areas, listed properties, larger schemes), we prepare and submit it end-to-end.
How long does a typical extension take?
A single-storey extension takes 12–16 weeks from breaking ground to completion. Double-storey runs 16–22 weeks.
Can we live in the house during the build?
For most rear extensions, yes. We dust-seal the working area and maintain access to your kitchen and bathroom.
How much does an extension cost?
In London, expect £2,500–£4,000 per square metre for a finished extension including kitchen and finishes. Use our calculator for a free estimate.
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