Insulated FTT U8 Thermo Roof Windows

The FTT roof window features an innovative structure which offers excellent thermal insulation parameters with an impressive Uw of 0.58W/m²K and is the most energy-efficient quadruple glazed window manufactured by FAKRO. These windows comply with the strict Passive House certification criteria and have received an official ‘ph B Certified Component’ accreditation from Passive House.

High energy-efficiency

A triple chamber glazing unit ‘U8’ with Ug = 0.3W/m²K is set in a specially designed sash frame, which offers wider wooden profiles in comparison with standard roof windows. This window is equipped with five airtight seals and having such a sustainable structureInsulated FTT U8 Thermo Roof Windows minimalises thermal bridging and provides an improved window insulation. When placing an order for an FTT U8 Thermo window it is supplied as a complete kit. Flashings are a necessity and within the kit an EHV-AT Thermo is provided to enable installation to be above the roof surface. On the inside of the flashing a flexible insulating material is glued to the inside of the flashing which adheres tightly to the window frame.

Another addition to the all-inclusive package is an XDK insulation flashing kit, which enables fast and efficient installation for thermal insulation, air permeable membranes and air tight membranes around the window. In order to reduce heat loss and money spent on energy bills, an application of comprehensive solution sits within the window to fulfil its energy-efficiency status.

Comfort of use

The sash can be opened like a pivot roof window but its axis of rotation is situated above the centre of the window therefore creating an easier access space and together it delivers more light! The sash holds itself in an open position ranging from 0 to 40 degrees and is supported by an innovative supporting mechanism.

Thermo roof windows

Lifetime glazing unit hail resistance warranty

The FTT U8 Thermo window is fully equipped with its glazing unit consisting of four toughened panes with increased resistance. Britain is renowned to have more bad weather than good so the FTT is great during heavy rainfall or hail. With unpredictable weather throughout the year, FAKRO have you covered by offering a lifetime warranty against hail.

Increased burglary resistance

Many of FAKRO’s roof windows come with the topSafe system to improve resistance against break-in attempts and to protect the sash from opening due to foot pressure if inadvertently stepped on.

For more information on our FTT U8 windows please email with any details of your project. To view our range of FTT windows please visit