Skylight Installation: What to Expect from Survey to Completion

Skylights — whether roof windows, flat rooflights, or lanterns — are among the most transformative glazing installations available to London homeowners. But a poorly specified or badly installed skylight is one of the most common causes of roof leaks. Here is how to get it right.

What This Guide Covers

• Accurate measurement of the roof structure is essential — timber rafters must not be cut without engineering sign-off
• Flashing kit specification must match the roof material — tile, slate, and felt each require different flashings
• Vapour control layer continuity around the skylight is the most commonly missed detail — causes condensation
• Building Regulations approval required for new roof openings in most circumstances
• Lead flashing should be used on all permanent installations — no plastic or foam alternatives

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?