Double-glazed roof windows are becoming increasingly popular for the modernizing of old attic skylights and as part of a loft conversion. They are supplied ready-glazed and fully equipped with catches and ventilators. Flashing kits to fit the frame and to suit high-profile or low-profile roofing material are also available.

Centre-pivoting sashes can be used for roofs with pitches between 15 and 90 degrees. Top-hung windows are available for pitched roofs between 15 and 75 degrees. A combined top-hung and central-pivot variant is also available to provide a large opening that can be used as an emergency exit.

Roof windows are relatively easy to fit, using ordinary woodworking tools. They can usually be installed from inside the roof space and the glass can be cleaned conveniently from inside. Accessories such as remote-opening devices and blinds are also available.

Cost is always a consideration when choosing roof windows, but take into consideration also the total area of glass that will be necessary to provide a suitable level of daylight in the room.The manufacturers of roof windows offer a standard range of sizes.

The height of the window is also quite important and is largely determined by the pitch of the roof. Manufacturers produce charts which give the recommended dimensions according to roof pitch. Ideally, if the window is to provide a reasonable outlook, the bottom rail should not obstruct the view from normal seat height, nor should it cut across the line of sight of someone standing. Broadly speaking, this means that the shallower the pitch of the roof, the taller the window needs to be. However, the top of the window should always remain

Start by stripping off the roof covering material over the area which is to be occupied by the window. The final placing of the frame will be determined by the position of the rafters and the roofing. Start by setting the bottom of the window frame at the specified distance above the nearest full course of slates and try to position it so as to have half or whole slates on each side.

Cut through the slating battens, roofing felt and rafters to make the opening, following the dimensions that are given by the manufacturer. Cut and nail horizontal trimmers between the rafters to set the height of the opening, and a vertical trimmer or trimmers to set the width..

Standard-size windows can be set side-by-side or placed one above the other to create a larger window; the widest single window available measures 1.34m (4ft 41/4in). When deciding on the size of a window, bear in mind its proportions and position in relation to the building’s appearance.

You probably will not need planning permission to install this type of window, but check if you live in a listed building or in a conservation area. However, the structural alterations will require Building Regulations approval, and so will a complete loft conversion.

The manufacturers of roof windows supply fixing instructions to suit installation in all situations. Below is a summary of one type of window fitted in a slate-covered roof. The frame for a tiled roof has a different flashing kit.

screw the window frame in place with the brackets provided. A guideline is clearly marked round the frame, and you must set this level with the surface of the roofing battens. Check that the frame is square by measuring across its diagonals to be sure they are equal.

Complete the outside work by fitting the slates and flashing kit, working up from the bottom of the frame. Replace the glazed sash.

Cut and nail plasterboard to the sides of the rafters on the inside and close the top and bottom of the opening with plasterboard nailed in the groove provided in the frame and to the timbers of the roof structure.

Finish off the joints with filler and tape, ready for decoration.

Double-glazed roof windows are becoming increasingly popular for the modernizing of old attic skylights and as part of a loft conversion. They are supplied ready-glazed and fully equipped with catches and ventilators. Flashing kits to fit the frame and to suit high-profile or low-profile roofing material are also available.

Centre-pivoting sashes can be used for roofs with pitches between 15 and 90 degrees. Top-hung windows are available for pitched roofs between 15 and 75 degrees. A combined top-hung and central-pivot variant is also available to provide a large opening that can be used as an emergency exit.

Roof windows are relatively easy to fit, using ordinary woodworking tools. They can usually be installed from inside the roof space and the glass can be cleaned conveniently from inside. Accessories such as remote-opening devices and blinds are also available.

Cost is always a consideration when choosing roof windows, but take into consideration also the total area of glass that will be necessary to provide a suitable level of daylight in the room.The manufacturers of roof windows offer a standard range of sizes.

The height of the window is also quite important and is largely determined by the pitch of the roof. Manufacturers produce charts which give the recommended dimensions according to roof pitch. Ideally, if the window is to provide a reasonable outlook, the bottom rail should not obstruct the view from normal seat height, nor should it cut across the line of sight of someone standing. Broadly speaking, this means that the shallower the pitch of the roof, the taller the window needs to be. However, the top of the window should always remain

Start by stripping off the roof covering material over the area which is to be occupied by the window. The final placing of the frame will be determined by the position of the rafters and the roofing. Start by setting the bottom of the window frame at the specified distance above the nearest full course of slates and try to position it so as to have half or whole slates on each side.

Cut through the slating battens, roofing felt and rafters to make the opening, following the dimensions that are given by the manufacturer. Cut and nail horizontal trimmers between the rafters to set the height of the opening, and a vertical trimmer or trimmers to set the width..

Standard-size windows can be set side-by-side or placed one above the other to create a larger window; the widest single window available measures 1.34m (4ft 41/4in). When deciding on the size of a window, bear in mind its proportions and position in relation to the building’s appearance.

You probably will not need planning permission to install this type of window, but check if you live in a listed building or in a conservation area. However, the structural alterations will require Building Regulations approval, and so will a complete loft conversion.

The manufacturers of roof windows supply fixing instructions to suit installation in all situations. Below is a summary of one type of window fitted in a slate-covered roof. The frame for a tiled roof has a different flashing kit.

screw the window frame in place with the brackets provided. A guideline is clearly marked round the frame, and you must set this level with the surface of the roofing battens. Check that the frame is square by measuring across its diagonals to be sure they are equal.

Complete the outside work by fitting the slates and flashing kit, working up from the bottom of the frame. Replace the glazed sash.

Cut and nail plasterboard to the sides of the rafters on the inside and close the top and bottom of the opening with plasterboard nailed in the groove provided in the frame and to the timbers of the roof structure.

Finish off the joints with filler and tape, ready for decoration.