Time to replace your roof windows?

Sometimes the smallest upgrade can make the biggest impact. Discover the difference replacing your old roof windows can make.

Learn more

Replacement-project-page_2000x2000.pngGBI Replacement - website headers

If your roof windows are 20+ years old, modern VELUX design could transform your home

Today's roof windows bring in more daylight, keep rooms warmer in winter, and significantly reduce energy bills - and replacing them is surprisingly straightforward.

Whether you're dealing with condensation, draughts, or simply want a brighter, more comfortable space, replacing makes a real difference.

What are the benefits of replacing roof windows?

Improved energy efficiencyWhen it comes to insulation and energy efficiency, an old roof window (even in good condition) is no match for a modern VELUX roof window.

It's easier than you thinkReplacing your roof window with a new VELUX roof window can be done in as little as 4 hours.

More daylight and fresh airModern VELUX roof windows have a larger glazing area, so replacing your old window with the same size will let in more daylight.

Signs it's time to replace

Noticing any of these? It might be time for an upgrade. Make your home more comfortable with modern VELUX roof windows.

Condensation between the panes
Draughts or poor insulation
Difficulty opening or closing
Faded or outdated appearance
Windows over 20 years old
Rising energy bills

Arrange my replacement

Attic kids room with sloped ceiling and VELUX roof window, toys and books.

What does roof window replacement involve?

Worried about disruption? Don't be.

Most VELUX roof window replacements are completed in just 4 hours with minimal mess.

New roof windows fit into existing openings, so there's no major building work - just a straightforward swap that makes an instant difference to your home's comfort and appearance.

Step 1

The roof window installers remove the flashing and roofing material surrounding your old roof window.

The old roof window can then be safely removed.

Worker installing a VELUX roof window on a sloped metal roof.

Step 2

The roof window installers make any necessary adjustments to the roof opening.

If a larger roof window is replacing your old roof window, or further roof windows are being added, the installers add supporting crossbeams to hold the larger or additional roof windows.

Step 3

The installer secures your new roof windows to the rafters of your roof. The flashing is then installed to keep everything weathertight.

The installer then replaces the tiles or slates along the edges of the flashing.

Step 4

Any internal cosmetic fixes, or new plasterboard, are applied.

This step typically won’t be required for a simple like-for-like replacement of the same size.

Step 5

The installer adds your chosen VELUX roof window accessories, such as blinds or shutters.

The installer will take the packaging and your old roof window away with them. Mess-free, stress-free, job done!

Make the most of your VELUX replacement

Ready to replace? Make sure you know the upgrade options available to you. Discover your options for better finish, more automation, added comfort - all within the same roof opening.

Let our Replacement Supply & Fit team advise you on your upgrade options and help you choose features that suit your lifestyle and budget.

Detailed crosscut of window frame showing layers of wood and metal.

Upgrade finish

Brighten your space with a fresh, bright, white maintenance-free interior finish.

It’s our most durable and robust finish. No future touch-ups or repainting required!

Open VELUX roof window in a room with a sloped ceiling, natural light entering.

Upgrade operation

Are your roof windows out-of-reach?

Solar roof windows can be effortlessly opened and closed with the touch of a button. They also close automatically in the event of rain.

Cross section of VELUX roof window, showing glass layers and frame.

Upgrade glazing

Do you live near busy roads or flight paths?

Keep the outside cold and noise at bay. VELUX triple-glazing brings better insulation and noise reduction.

Attic workspace with sloped ceiling and VELUX roof windows, desk and chair.

Upgrade with blinds and shutters

Complete the transformation with new internal blinds and external heat protection.

The perfect final touch for added style and comfort.

Our services

Replacement Supply & Fit service

Find a VELUX Certified Installer

Looking for a
replacement cost?

VELUX Design Service

Frequently asked questions

Will I need to redecorate after a replacement?

For a straightforward like-for-like replacement, you won't need to redecorate. VELUX roof windows have been available in the same sizes for decades, so there's no damage to your home when replacing.

The replacement process is clean and contained to the roof window area itself. Most homeowners are surprised by how tidy the process is - your room will look just as it did before, just with a newer, better-performing roof window.

How much does it cost to replace a VELUX roof window?

Replacement costs can vary based on your roof window’s size, spec, and installation complexity. Get an approximate quote using our replacement configurator.

Ready to push the button on your replacement project? Contact our Supply & Fit team for accurate pricing - including installation - based on your specific roof window.

Do I need Building Regulations approval?

Like-for-like replacements typically don’t require Building Regulations approval. However, if you're making structural changes (enlarging the opening, adding roof windows, significantly altering the roof), Building Regulations will apply.

If you're upgrading your window as part of a broader loft conversion or renovation, your project may already be subject to Building Regulations.

Can I upgrade to an automated roof window when I replace?

Absolutely! Replacement is the perfect opportunity to upgrade. You can switch from a manual window to solar-powered, add blinds and shutters, or upgrade to triple glazing - all within the same roof opening.

Our Supply & Fit team can walk you through the upgrade options and help you choose features that suit your lifestyle and budget.

How do I know what size VELUX roof window I have?

Every VELUX roof window has a data plate (type sign) located on the inside, usually on the top right when the window is open. It shows the size code (like GGL MK04 or FK06) and manufacturing date. Watch our short video on how to identify your type sign here.

If you can't find it or need help identifying your roof window, reach out to the Supply & Fit team - we’ll help you work out exactly what you have - and what replacement options are available.

Can I replace my old VELUX roof window with a different size?

In most cases, yes - but it depends on your roof structure. If you want to go larger, you may need to adjust the roof timbers, which can add time and cost. If you're replacing with the same size, it's a straightforward swap that fits the existing opening.

For adding more – or larger – roof windows, speak to the VELUX Design Service. Our dedicated team of daylight experts will bring your renovation vision to life.

My old roof window isn’t branded VELUX. Can I choose a VELUX replacement?

Yes! As the original roof window brand, VELUX set the sizing standards that competitors have copied for decades. This means replacing another brand with VELUX is simple - your existing opening likely matches a standard VELUX size.

If adjustments are needed, trusted Certified Installers will handle any tweaks required, ensuring your new VELUX roof window fits perfectly.

Upgrade to the original: Speak to our Supply & Fit team today.

How long does the VELUX guarantee last?

Using our Replacement Supply & Fit team, you’ll benefit from our full guarantee:

10-year guarantee on roof windows and 3-year guarantee on blinds
10-year installation guarantee from VELUX Certified Installers
Our VELUX Certified Installer network are trusted, vetted partners