Velux Window Servicing: Cost & What's Involved

Velux roof windows are mechanically robust and can last for decades with reasonable care, but they rely on moving components (hinges, locking handles, the ventilation flap and draught seals) that need periodic attention.¹ Neglecting them leads to stiff operation, draughts, condensation at the frame edges, and ultimately costly repairs that a simple service would have prevented.

In practice, most UK homeowners only service a Velux window after something noticeably goes wrong. A proactive approach costs far less than a reactive one.

What a Velux Service Involves

A thorough service of a roof window covers the following:

Mechanical components:

• Cleaning and lubricating the hinges and fittings
• Checking the ventilation flap and air filter, and the actuator linkage on electric models
• Checking and adjusting the locking handles and latch mechanism
• Inspecting and tightening any loose screws on the frame or hardware

Seals and weatherproofing:

• Inspecting the draught seals around the sash perimeter and replacing any that are compressed or torn
• Checking the junction between the frame and the flashing, where the window meets the roof
• Inspecting flashings for lifted edges, cracked sealant, or moss growth that could direct water to the frame

Glass and frame:

• Cleaning the frame channels and drainage slots
• Checking the glazing unit for seal failure (indicated by condensation between panes)
• Inspecting the frame for any signs of rot (timber-framed models) or corrosion at fixings

Controls (electric and solar models):

• Testing the motor operation and rain sensor
• Checking the remote or wall switch pairing
• Inspecting wiring connections at the actuator

For electric windows, Velux recommends replacing the gas springs and the motors within 10 years of installation.²

Cost of Velux Servicing (UK, 2026)

Contractors who specialise in roof windows, rather than general builders, are often both cheaper and more thorough. Velux lists certified installers on its website, and independent roofers and window specialists can also buy genuine Velux spare parts and service kits.³⁴

If you have several roof windows, booking a single visit for all of them means paying one call-out charge rather than one per window.

How Often Should You Service a Velux Window?

Velux recommends lubricating the fittings and hinges at least once a year.³ It also advises clearing leaves and debris from the flashing once a year so rainwater can drain freely.² The intervals in the table above are a practical rule of thumb for a professional service rather than a Velux requirement. In practice, a homeowner can carry out a basic visual and lubrication check themselves annually (see below) and reserve the professional service for every other year.

DIY Servicing: What You Can Do Yourself

A basic annual check takes 20–30 minutes per window and requires no specialist tools:

1. Lubricate the hinges: Use the lubricant from a Velux service kit, or a PTFE or silicone spray, and apply it to the hinges and fittings, wiping away any excess. Keep lubricant off the glass, because Velux advises avoiding any contact between silicone and the pane.²
2. Clean the air filter: The air filter can be removed and washed with ordinary household cleaners.² Rotate the sash into its cleaning position to reach it.
3. Check the draught seal: Run your finger around the sash edge with the window closed, any gaps or compressed areas where light is visible are worth flagging for a professional replacement.
4. Clear debris: Brush leaves and debris out of the frame channels and away from the flashing so rainwater can drain freely.
5. Inspect the flashing: From ground level with binoculars, look for any lifted or loose flashing sections, cracked sealant, or moss building up around the flashing. If in doubt, arrange a roofer to inspect from the roof.

Do not attempt to adjust the hinges or replace seals without the model-specific Velux instructions, because incorrect adjustment can cause the window to bind or fail to close flush.

Servicing vs Repair vs Replacement

Velux puts the average cost of supplying and fitting one replacement roof window through its own service at between £1,200 and £1,600, depending on the window’s size and specification.¹

Velux Guarantees and Warranties

New Velux windows carry a 10-year guarantee.⁵ The guarantee document lists the glazing unit as part of the roof window it covers, so there is no separate, longer term for the glass.⁶ On solar and electric roof windows the electrical components have a 5-year guarantee, which you can extend by a further 5 years by registering the window.⁵ The guarantee does not cover defects caused by a failure to maintain the window as its instructions describe, so keeping a note of service dates is worthwhile while your windows are within the guarantee period.⁶

For older windows, Velux still sells parts, including a DIY service kit for roof windows made before 2014.³ To order the right part, check the type plate in the right-hand corner of the top sash, behind the ventilation flap; every Velux roof window made after 1968 has one.²