Roof Lanterns for London Kitchen Extensions: Cost & Design Guide

Roof lanterns have become the must-have feature for kitchen extensions across London — from the Victorian semis of Wimbledon and Richmond, to the stucco townhouses of Kensington and Chelsea. Here is a complete guide to costs, sizes, and what to expect from installation.

What This Guide Covers

• Roof lantern cost London 2025: £3,000–£8,000 depending on size
• Aluminium roof lanterns dominate the market — low maintenance, slim sightlines
• Most popular sizes: 1.5m x 2m to 3m x 4m for London kitchen extensions
• Thermal performance: look for Uw below 1.5 W/m²K for energy efficiency
• Planning permission not usually required if the extension already has approval

Introduction

London homeowners face unique challenges when it comes to glazing — from period properties with sash windows in conservation areas, to modern developments requiring structural glass installations. Getting the right advice before you commit can save you significant time and money.

At BuilderFix Glazing, we have completed thousands of glazing jobs across Greater London and Surrey — from emergency repairs in Kensington and Chelsea, to bespoke walk-on glass installations in Mayfair and Belgravia. This guide is based on real experience and the questions our customers ask us most often.

What Does This Typically Cost in London?

Costs vary depending on the type and size of work, the glass specification, frame material, and access. As a general guide, always obtain a free written quote before committing — this protects you from unexpected charges.

At BuilderFix Glazing, we provide free, no-obligation written quotes for all work. Our prices are transparent and fixed before we start — no surprises on the invoice.

What to Ask When Getting a Quote

• Is the price fixed, or could it change once work starts?
• What glass specification is included?
• Are all fixings, sealants and finishing included?
• What compliance documentation will I receive?
• What happens if there is an issue after completion?