House Extension
in Barnet
Compare quotes from vetted Barnet extension builders for single-storey, double-storey and rear extensions. Transparent pricing from £21,500. Free, no-obligation quotes — results in 24 hours.
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How Much Do House Extension Cost in Barnet?
Real prices from completed projects in Barnet and the surrounding area. Costs vary by size, specification and access — use these as a starting guide, then get 3 free quotes for your specific project.
The most popular choice for UK terraces and semis. Adds a kitchen-diner or extra living space at ground level. Typically 3–5m deep, completed in 10–14 weeks.
Get quotes for this →Maximum space gain in a single build — adds a ground-floor room and a bedroom above. Strong ROI in most UK property markets. Requires full planning permission.
Get quotes for this →Ideal for terraced homes with a narrow side alley. Transforms a cramped kitchen into a full-width open-plan space. Often combined with a rear extension.
Get quotes for this →Costs depend on size, spec and access. The best way to know your exact price is to compare 3 quotes from vetted local specialists.
Get free quotes →Barnet pricing note: Building costs in London are typically 30–40% above the national average, driven by higher labour rates, congestion charges, stricter planning requirements and premium material delivery costs. Inner London boroughs (Zones 1–2) command the highest rates. Prices shown are indicative ranges for Barnet and London. Always get at least 3 written quotes before committing to any builder.
House Extension Specialists Who Know Barnet
Home renovation activity in Barnet continues to grow year on year. The area's varied housing stock, from older stone-built properties to new-build estates, means there is always strong demand for skilled, experienced local builders.
Before any builder appears on our Barnet platform, we carry out a full vetting check covering public liability insurance, trade qualifications, company registration and verified customer feedback. Only builders who pass every stage are listed.
Our Barnet builder network covers extensions, loft conversions, kitchens, bathrooms, roofing, driveways and more. Get up to 3 free, no-obligation quotes within 24 hours and choose the builder that best fits your project and budget.
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What Barnet Homeowners Say About Our House Extension Specialists
Found an excellent builder through BestBuilders for our extension project. The quote process was straightforward, the builder was professional throughout and the finished result exceeded our expectations.
We used BestBuilders to find a loft conversion specialist. Received 3 competitive quotes within 48 hours and the builder we chose delivered on time and on budget. Highly recommended.
Good experience overall. The kitchen renovation was completed to a high standard. Minor delays on materials but the builder kept us informed. Would use BestBuilders again.