Conventional – traditional slim box sash windows

This is the slimmest traditional box sash double glazed window in the United Kingdom measuring just over 5 inches in depth, perfectly suitable for properties in conservation areas.. This slim sash window fits in to the more compact modern window space without intruding into the room or competing with radiators for space, comfortably replacing the original window.

Our most popular choice for new and replacement double glazed Sash Windows, particularly where internal shutters or decorative features restrict the depth of the new windows. Radiators often need repositioning to accommodate the new double glazed windows but this is not necessary with the Slim Box Sash even when positioned directly below the window.

The Slim Box Sash is also perfect for sash box bay windows and can maintain the original Glass areas and match window proportions when used in conjunction with our Slim Bay detail.

The slim double glazed units take advantage of the high insulating levels provided by krypton gas – allowing for a very narrow gap between the glass.

On the exterior of the Slim Box Sash Window the appearance is consistent with our Sash Window collection with the use of slim meeting rails and glazing bars and the use of traditional mouldings.