Home & Outdoors

How to Clean a VELUX Skylight or Roof Window

VELUX makes fixed skylights, manual and powered venting skylights, tubular units, center-pivot roof windows, top-hinged windows, and CABRIO balcony roof windows. Their access and cleaning positions are not interchangeable. VELUX says compatible roof-window sashes can rotate 180 degrees and be secured with the barrel bolt for outer-pane cleaning; their removable ventilation filter can be washed with ordinary household cleaner. A fixed or out-of-reach skylight does not offer that same indoor access and may require a trained professional. Find the product ID first, keep your feet off the glass and roof, and let the exact model instructions determine what can safely move or detach.

Primary reference: VELUX official roof-window cleaning and maintenance guidance. Always check the manual for your exact model.

Quick reference

Identify
Use the VELUX product ID before moving a sash or removing parts.
Access
Rotate only a compatible roof window and lock its barrel bolt.
Glass
Use mild soap, clean water, soft tools, and no abrasive blades.
Filter
Wash only removable model-approved filters and reinstall fully dry.
Professional
Escalate roof access, cracks, leaks, failed glazing, and powered faults.

What you will need

  • The product ID and manual for the exact VELUX unit
  • Soft lint-free cloths and a nonabrasive sponge
  • Clean water and mild soap
  • A soft brush for compatible exterior glass
  • A stable indoor step stool only for safely reachable controls
  • Towels to protect flooring and sills
  • A professional skylight or window cleaner for roof access

Step-by-step instructions

Step 1: Find the product ID and choose the access branch

Locate the VELUX serial or product code using the company's Product ID guide. Determine whether the unit is a center-pivot or CABRIO roof window designed to rotate, a top-hinged window, a manual or powered venting skylight, a fixed skylight, or a sun tunnel. Do not copy a rotating-sash procedure onto fixed glass or powered hardware.

Step 2: Make the indoor area safe

Choose a dry calm day, close powered shades, turn off powered operation according to the manual, and place towels below. Use only a stable indoor platform on a level floor. Never stand on furniture, climb onto the roof, lean body weight through an opening, or step on skylight glass. Out-of-reach exterior work belongs to a properly equipped professional.

Step 3: Remove loose interior dust

Dust the interior pane, frame, sash, control bar, and sill with a soft dry cloth or brush. Work from top to bottom so debris does not cross cleaned glass. Keep grit out of hinges, motors, rain sensors, and weep or drainage paths. Vacuum only with a soft attachment held off the finish, and never pull on wires, blind cords, or insect-screen mesh.

Step 4: Wash the accessible interior pane

Use clean water with a small amount of mild soap on a soft nonabrasive sponge or cloth. Wipe gently, then remove residue with clean water and dry with lint-free cloth. Avoid razor blades, abrasive powder, ammonia-heavy cleaner, pressure steam, and adhesive tools that can scratch glass or damage coatings, seals, wood finish, and plastic trim.

Step 5: Rotate only a compatible roof-window sash

If the exact VELUX instructions show a cleaning position, rotate the sash 180 degrees and secure it with the barrel bolt at the bottom of the frame before touching the outer pane. VELUX documents this feature for CABRIO and compatible roof windows. Keep hands clear of pivots and never rely on friction alone. Do not force a top-hinged, powered, or fixed unit to imitate this motion.

Step 6: Clean the exterior pane by the approved route

For a safely locked rotating sash, wash the now-accessible outer glass with mild soapy water and a soft tool, rinse in a controlled way, and dry. VELUX also permits water and soap solution with a nonabrasive cleaner and soft brush on tubular-skylight glass. For fixed or roof-only access, hire a professional rather than reaching from a ladder or walking on roofing.

Step 7: Clean screens and ventilation filters separately

Remove an insect screen or air filter only if the exact guide shows how. VELUX says the filter in compatible roof windows can be removed from its rail and washed with ordinary household cleaner. Rinse away residue and let it dry completely before reinstalling. Use gentler hand cleaning on screen mesh; replace torn, brittle, or misshapen parts.

Step 8: Restore, inspect, and address condensation causes

Return a rotating sash to normal position, release and lock hardware exactly as directed, restore power, and test operation from the floor. Check seals, flashing-visible areas, frame finish, drainage, shades, and sensors without dismantling them. Moisture between panes, recurring leaks, cracked glass, failed motors, or damaged flashing cannot be cleaned away and requires VELUX or qualified installer service.

Specific cleaning questions

Open a question for a concise answer about stains, odors, safety, frequency, and troubleshooting.

Can I clean the outside of a VELUX skylight from indoors?
Only compatible rotating roof windows offer a documented 180-degree cleaning position. Fixed and many venting skylights require a different access plan, often a professional.
How do I identify my VELUX model?
Use the product or serial code on the unit and VELUX's Product ID guide. Model identification determines sash movement, filters, glazing, and powered-hardware precautions.
Can I stand on skylight glass?
No. Never stand, kneel, or place a ladder on skylight glass. Use safe indoor access or a properly equipped professional.
What cleaner is safe on VELUX glass?
Use clean water, mild soap, and a soft nonabrasive tool unless the exact glazing manual specifies otherwise. Avoid blades, abrasive pads, and harsh chemicals.
Can a VELUX roof-window air filter be washed?
VELUX says filters in compatible roof windows can be removed and washed with ordinary household cleaner. Dry fully and confirm your exact model first.
How do I clean a powered VELUX skylight?
Disable operation as its manual directs, clean only accessible surfaces, and keep moisture away from motors, controls, wiring, and rain sensors.
Why is there fog between the panes?
Moisture inside an insulated glass unit usually indicates a glazing-seal problem, not surface dirt. Contact VELUX or a qualified installer.
Will cleaning stop condensation on the room side?
Cleaning removes residue but does not correct indoor humidity or cold-surface conditions. Improve ventilation and investigate recurring condensation according to VELUX guidance.