The VELUX 2in1 guide - 2in1 sizes, features, benefits and more.

Posted by Lawrie Fraser on 27th February 2023

VELUX, the leading manufacturer of roof windows, has launched its all-new 2in1 roof window, which is an innovative and versatile product that offers both daylight and fresh air in a single unit. In this blog, we'll explore the features and benefits of the VELUX 2in1 roof window and why it is a game-changer for homeowners and architects alike.

What is a VELUX 2in1 roof window?

The VELUX 2in1 roof window is a new product that combines a roof window and a top-hung window in one unit. It features a unique design that allows the sash to be opened in two ways: either as a traditional roof window, where the sash is hinged at the top and opens outwards, or as a top-hung window, where the sash is hinged at the bottom and opens inwards. This dual functionality provides homeowners with the best of both worlds: they can enjoy natural daylight and fresh air from the same unit, all while saving space and installation costs.

Features and benefits of the VELUX 2in1 roof window.

Dual functionality: The VELUX 2in1 roof window offers homeowners the flexibility of having a fixed roof window and a top-hung or centre-pivot window in a single unit. , This is particularly useful for homes where space is limited, as it eliminates the need for two separate windows. It also adds the same amount of daylight without doubling the cost of the roof windows.

Increased ventilation: The top-hung or centre-pivot window function of the VELUX 2in1 roof window allows for increased ventilation, as the sash opens inwards on the centre-pivot models and outwards on the top-hung models which allows fresh air to circulate more effectively. This is particularly useful during the summer months, when homeowners want to keep their homes cool and well-ventilated.

Easy to Use: VELUX 2in1 roof windows are easy to use, with a standard operating roof window. The opening of the operating sash is just as easy and effortless as the standard single VELUX roof windows.

Energy Efficient: VELUX 2in1 roof windows are designed to be energy-efficient, with a tight seal that helps to prevent heat loss and keep your home warm in the winter. The Solar option also allows you to operate your roof window without using mains powered energy.

Versatile: VELUX 2in1 roof windows come in a range of sizes and styles, so you can choose the perfect window to suit your home's design and your personal preferences.

Easy to Install: VELUX 2in1 roof windows are designed to be easy to install, with a simple process that can be completed by a professional installer.

VELUX 2in1 roof window sizes:

VELUX GGLS 2in1 Centre-Pivot Roof Window – Available in solar.

VELUX GPLS 2in1 Top-hung Roof Window – Manual only.

FFK06 – 127cm (W) x 118cm (H)

FFK08 – 127cm (W) x 140cm (H)

FMK06 – 139cm (W) x 118cm (H)

FMK08 – 138cm (W) x 140cm (H)

FPK06 – 155cm (W) x 118cm (H)

FPK08 – 155cm (W) x 118cm (H)

MMK06 – 151cm (W) x 118cm (H)

MMK08 – 151cm (W) x 140cm (H)

Available glazing’s.

Double glazing – VELUX 2in1 roof window double glazing is a 2-layer pane of glass, equipped with a laminated inner and toughened outer pane. The VELUX double glazing is some of the best performing double glazing’s in the market. Keeping your homes thermal efficiency and security in top form. The VELUX glazing is coated in a special Low-E coating and argon gas that is vacuum sealed in the space between the interior and exterior panes of the glass.

Triple glazing – The 2in1 roof window triple glazing is a 3-layer pane of glass, equipped with 3 panes two of which are toughened outer panes and a laminated outer pane. The VELUX triple glazing Is the best glazing for all around thermal efficiency, security, and noise reduction. The VELUX glazing is coated in a special Low-E coating and argon gas that is vacuum sealed in the space between the interior and exterior panes of the glass.

Technical features.

  • Can be installed in roof pitched between 15° and 90° to the horizontal.
  • Enjoy an extensive view to the outside and more daylight due to extra slim frame profiles.
  • One frame module allows a simple well-known installation process with few components.
  • One-piece top cover and slim profile covers feature a very aesthetic integration in the roof.
  • The glazing comes standard with premium features like safety lamination, toughened glass, UV filter and our unique rain noise reduction.
  • Upgrade to a remote-controlled mains- or solar-powered motor for extra convenience.
  • Get more control over your indoor climate with our wide range of accessories.
  • Quickly and easily add blinds by simply clicking them into the pre-fitted brackets.
Window Characteristics Performance
Thermal transmittance (U-value) 1.3 W/(m2K)
Light transmittance (τ,v) 0.68
Total solar energy transmittance (g-value) 0.46
Sound insulation (Rw) 34(-1;-4)
Air permeability, [class] 4
External fire performance - British [class] npd
External fire performance - European [class] npd
Impact resistance [class] 3
Load-bearing capacity of safety devices
Reaction to fire [class] C-s1,d2
Resistance to snow load See glazing composition
Resistance to wind load [class] C3
Water tightness [class] 9A

Control bar – The aluminium control bar allows effortless opening and closing of the window. It can also lock the ventilation flap in the ventilation position.

Detachable sash – The fixed sash is detachable and can be taken out for an easier process during service or installation from the inside.

Blind bracket, manual – Easily install blinds on the window without the need for extra tools. Simply click on the blind in the pre-fitted brackets.

Ventilation flap – The ventilation flap can be used for ventilation with a closed window. The ventilation flap is connected to the top sash with the lock casing.

Frame hinge – This hinge allows for a reliable operation and enables the sash to be rotated for easy cleaning of outer glass.

Interior insulation – VELUX ThermoTechnology™ insulation is integrated into the top frame sides of the window to increase energy-efficiency.

Barrel bolt – The barrel bolt can be placed into the integrated barrel bolt. This helps to secure the sash in 180 pivot position to clean the outer pane of the window.

Headlock – When closed, the window is locked firmly into place by the headlock.

Further help?

View our installer guide.

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