Sash Window Restoration: Is It Worth It?

London has more original sash windows than any other city in the world. From Hampstead's Georgian townhouses to Kensington's stucco villas and Islington's Victorian terraces, sash windows define the city's streetscape — and its most desirable properties.

What This Guide Covers

• Sash window restoration cost: £400–£900 per window including draught-proofing
• Full replacement cost: £800–£2,500 per window — not always better
• Restored sash windows can last another 50–100 years
• Draught-proofing alone reduces heat loss by up to 86%
• Heritage areas (Mayfair, Belgravia, Kensington) require planning consent to replace sashes

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?