In a passive building, the use of roof windows requires them to be highly technologically advanced. The basic principle of passivity is to avoid any elements that increase the heat transfer coefficient of external partitions, in this case the roof partition.. Each element is like a chimney, sewage ventilator or window "cuts" this partition and increases the value of the heat transfer coefficient by creating the so-called. thermal bridge.
Inserting a "traditional" roof window into a passive house would cause too much heat loss and the building would not receive a passivity certificate issued by the Passive House Building Institute.
The following technical guidelines and parameters must be met:
• współczynnik przenikania ciepła dla szyby Ug = 0,5 W/(m2 • K)
• współczynnik dla całego okna: 0,95 W/(m² • K),
• przepuszczalność energii słonecznej: no less than 45%,
• przepuszczalność światła LT 65%,
• budowa szyby: two-chamber with krypton,
• szczelny montaż w konstrukcji budynku (pressure test),
• wyposażenie okien dachowych i kolankowych w rolety zewnętrzne szczelne po zamknięciu i dodatkowo ocieplone,
• specjalny kolor RAL dostosowany do kolorystyki budynku,
• radiowy system sterowania siłownikami otwierającymi okna oraz rolety zewnętrzne,
• intelligent closing and opening control program (automatic closing at night and opening in the morning,
• sterownik radiowy tzw. spaceship that recognizes sunrise and sunset at certain times of the year.
In the passive house, combinations of roof windows with a pivot structure and L-shaped windows were used.
The FT pivot window is the most popular roof window construction. Hinge positioned halfway up the window, allows the sash to be rotated and left in the open position. The sash can also be rotated around its axis by 180 ° and locked with a locking bolt, which allows for convenient and safe cleaning of the outer pane of the window. One of the roof windows in the set is operated by a handle with a two-stage micro-ventilation, located at the bottom of the sash. The second window is opened by an electric actuator connected to the control unit and operated by a remote control or a wall switch. The windows are made of pine wood, vacuum impregnated and painted with acrylic lacquer. Pivot windows can be installed in the roof with an inclination angle from 15 ° to 90 ° with a sealing flange.
The FL elbow window is a pivot window that is installed in the lateral wall as an additional element "extending" the roof window. Thanks to the use of a L-shaped window, the illumination of the room is improved and the field of view is increased. The L-shaped window can be connected to a roof window of any design.
The EU sealing flange is used to connect the windows from the outside. On the inside, the windows are connected with a masking strip, made of pine wood, matched to the windows.