Extension Builder in London

Finding a reliable extension builder in London means working with someone who understands the capital's diverse property stock—from Victorian terraces in Clapham and Islington to post-war semis in the outer boroughs and converted warehouse lofts in Shoreditch. London's housing shortage has made extensions essential, whether you're adding a kitchen-diner in Wimbledon, a rear extension in Bromley, or a loft conversion across one of the city's countless converted properties. A skilled extension builder in London must navigate strict building regulations, Conservation Area restrictions in areas like Chiswick and Hampstead, and the logistical complexity of working in densely built neighbourhoods. You need a builder who knows your specific London postcode's planning quirks, can manage neighbours in close proximity, and delivers results that add genuine value to your property.

Extension Builder Services in London — What BizHub365 Helps You Manage

Single and double-storey rear extensions

Running a Extension Builder Business in London

London's extension market is booming. From Victorian terraces in Clapham and Wandsworth needing rear extensions, to semi-detached homes in suburban zones like Croydon and Barnet seeking loft conversions, demand is relentless. Conservation area restrictions in neighbourhoods like Dulwich and Hackney drive premium costs and require specialist knowledge. Builders serving London often travel 20+ miles across multiple boroughs, making scheduling and job costing critical.

Frequently Asked Questions

What should I expect to pay for a single-storey extension in London?

A single-storey rear extension typically costs £2,000–£6,000 per square metre in Greater London. Victorian terraces in central areas (Islington, Southwark) attract premium costs; outer zones (Croydon, Barnet) may be 15–20% lower. Building regulation, structural surveys, and party wall agreements add £3,000–£8,000.

How long does planning permission take in London?

Most London boroughs target 8 weeks for determination. Extensions under permitted development rights (single-storey, under 4m height, no more than 50% extension of original footprint) need no permission. Conservation areas and listed buildings always require formal application.

Do I need Building Regulations approval for an extension in London?

Yes. All extensions in London must comply with Building Regulations Part L (energy), Part M (access), and structural standards. You'll need a Control Certificate or Regularisation Certificate from your local authority or an approved inspector like LABC or NHBC.

Are extension builders in London VAT registered?

Most London extension builders operating above the VAT threshold (£85,000 turnover) are registered. Many use CIS (Construction Industry Scheme) for labour-only subs. Check your builder's VAT number on the HMRC register before commissioning.

Not ready to sign up? Get free tips for running your extension builder business

We'll send you useful insights for extension builder businesses — invoicing, HMRC tips, and tools to help you grow.

Build Your Business as Well as Your Extensions

Join extension builders across London using BizHub365 to manage multi-stage invoicing, material tracking, and HMRC compliance. Phase-based quotes, site expense capture, and CIS deduction support. Start your free trial today—no credit card needed.

Are you a Extension Builder?

Run your extension builder business on BizHub365

Invoicing, expenses, HMRC compliance, quoting and more — everything a extension builder business needs, in one platform.

Start Free Trial

No card required to start

Why Extension Builders Choose BizHub365

Running your extension building business in London means juggling multiple permits, split invoices across boroughs, and tracking materials costs on sprawling projects that span months. BizHub365 lets you invoice each phase separately, track labour and materials against budget, and stay HMRC-compliant across different VAT zones. With built-in CIS support, you can claim deductions for labour-only subcontractors, and the mobile expense scanner captures site photos and receipts without leaving the scaffold. Planning control applications, building regulation sign-offs, and payment schedules all demand meticulous records—BizHub365 automates the paperwork so you focus on the build.

Platform Features

Create & send professional invoices
Track expenses and receipts
HMRC MTD VAT compliance
Manage quotes and jobs
Customer CRM and bookings
Payroll and employee management
AI-powered business assistant
From £29/month — no setup fee

How Much Does a Extension Builder Cost?

See typical price ranges for extension builder services in London, including what affects the final cost.

View London Pricing Guide

How Does BizHub365 Compare on Price?

See what it costs to piece together QuickBooks, Salesforce, Calendly and more — versus BizHub365 One at £29/month.

Try the Price Calculator

Extension Builders in Other Areas

View All Locations