Fixing and buying guide

What this window is and who it is for

This is a top-operated centre-pivot roof window with integrated burglary-resistant security features. The GGL MK04 is suitable for residential properties where security is a priority, including loft conversions, attic rooms and upper-floor spaces. The white painted finish suits most interior colour schemes. It works best in roof pitches between 15 and 90 degrees and is compatible with standard VELUX installation kits and flashings for your roof type.

Key features and performance

The window combines security with comfort and convenience. The 2-layer glazing reduces heat loss and improves thermal comfort. The top control bar can be opened to a ventilation position, allowing fresh air circulation even when the window is closed. The removable and cleanable ventilation filter keeps dust and insects out while you ventilate. The 180-degree rotation capability makes cleaning the outer glass safe and straightforward from inside your home. The centre-pivot design means you can open and close the window easily, even if furniture is positioned underneath.

• Integrated frame locks and extra strong hinges for security
• Laminated internal glazing and toughened external glazing for impact resistance
• 2-layer glazing for thermal efficiency
• Top-operated control bar with ventilation position
• 180-degree rotation for safe external glass cleaning
• Removable ventilation filter
• Pre-fitted brackets for quick blind installation

Sizing and compatibility

The 78x98cm size (MK04) is a standard mid-range roof window dimension. Before purchasing, confirm your roof pitch falls within the 15 to 90 degree range. Check your existing roof structure and rafter spacing to ensure the window opening can be properly prepared. You will need to purchase the correct flashing kit for your roof covering type (slate, tile, felt or metal). The pre-fitted blind brackets mean compatible VELUX blinds can be clicked into place without additional fixings.

Pre-installation checks and preparation

Measure your roof opening carefully and verify the 78x98cm dimensions fit your space. Check that your roof pitch is suitable and that rafters are spaced to accommodate the window frame. Ensure you have the correct flashing kit for your roof material. Clear the installation area of any obstructions and have the necessary tools ready. If you are not experienced in roof work, consider hiring a qualified installer. The white painted finish is ready to install; no additional finishing is required before fitting.