Roof windows: how to choose the right window for your attic
07.10.2026
A roof window gives an attic daylight, fresh air and a view. A wrong choice is hard to correct once the roof is covered, so it pays to decide before ordering. This guide walks through five decisions: opening type, material, glazing, size and position. The examples come from the Fakro roof windows that Ymalko offers in Montenegro.
1. Opening type
- Centre-pivot window. The sash turns around a central axis, up to 180°, so the outer pane can be cleaned from inside. It is the most common choice for rooms, for example the FTP-V.
- Raised pivot. On the FYP-V proSky the pivot sits above the middle of the window, so even a tall person can stand at the open window. The sash stays in any position from 0° to 45°.
- Two ways of opening. The FPP-V preSelect MAX opens top-hung up to 45° for the view and ventilation, and pivots for cleaning. A switch on the frame selects the mode.
- Balcony window. On the FGH-V Galeria the open sashes form a small balcony.
- Electric control. For windows out of reach there are Z-Wave, WiFi and Solar versions. A rain sensor closes the sash by itself when rain starts.
- Roof access. For access to the chimney and the roof, use a side-hung window or a roof hatch, and for flat roofs a dedicated access window.
2. Wood or PVC
Wooden roof windows are made of pine, vacuum-impregnated and lacquered. They give a warm look and are the best choice for living rooms and bedrooms.
For kitchens and bathrooms there are two solutions. The first is a wooden window with three coats of white polyurethane lacquer, such as the FTU-V. The second is a PVC roof window, such as the PTP-V: PVC profiles do not absorb moisture and need no painting, so they suit rooms where humidity stays high for a long time.
3. Glazing and thermal insulation
The Uw value shows how well a window insulates. The lower the number, the less heat the window loses.
- Double glazing: Uw about 1.3 W/m²K.
- Triple glazing: Uw about 1.0 W/m²K.
- Windows for energy-efficient buildings: the FTT U6 has Uw 0.8 W/m²K.
- Windows for passive houses: the FTT U8 Thermo has Uw 0.58 W/m²K.
Above beds and seating, choose a window with a laminated inner pane. In summer, sun protection matters more than the glazing itself: an external awning or roller shutter stops the heat before it reaches the glass. The accessories also include internal blackout blinds and an insect screen for roof windows.
4. Roof window sizes
Standard sizes of Fakro roof windows, width x height in centimetres:
- 55 x 78, 55 x 98
- 66 x 98, 66 x 118
- 78 x 98, 78 x 118, 78 x 140, 78 x 160
- 94 x 118, 94 x 140
- 114 x 118, 114 x 140
- 134 x 98
Not every model comes in every size, so confirm the size before ordering.
How much glass do you need? Fakro recommends that the glazed area in living spaces is at least one eighth of the floor area. A 16 m² room needs at least 2 m² of glass. Several smaller windows give more even light than one large one.
The rafter spacing sets the width of the window. The window has to fit between the rafters. For a wider window the rafters must be altered, and that is a job for a roof carpenter.
5. Installation height and roof pitch
Most roof windows are installed in roofs with a pitch from 15° to 90°. The recommended height of the bottom edge is 1.1 to 1.4 m above the floor, so you can see out both sitting and standing. The lower the roof pitch, the higher the window goes.
The flashing is ordered together with the window and is chosen by roof covering: one type for flat coverings, another for profiled coverings such as tiles. A Thermo flashing further improves the insulation of the joint between window and roof.
Checklist before ordering
- Roof pitch and type of covering
- Rafter spacing
- Use of the room: living space, kitchen or bathroom
- Floor area
- Whether the window is within reach
- Sun protection and insect screen
Roof windows in Montenegro
See the roof window range:
Models mentioned in this guide:
Send us the roof pitch, the type of covering and the room dimensions, and you will get a model recommendation and a quote.
Contact Ymalko Montenegro for a quote