Vertical Sliding Windows

From the 1960’s to the 1980’s many flats and apartments were constructed and fitted with original metal sash windows. With many of these windows now coming to the end of their useful life after several decades, you will be looking for an authentic sash window to replace them.  This will be the case particularly if windows will be required for an apartment building that has strict criteria for replacing like for like, or if you live in a property whereby the original metal sash windows are part of the property aesthetics.

Capital Windows offer a high quality, authentic window in aluminium


Capital Windows provide the unique Alumatherm sash window bringing all the aesthetics of the original sash windows combined with the latest in modern aluminium window technology.  Offering the latest in modern window specifications such as good thermal efficiency, high security and high specification double glazed units as well as impressive aesthetics so important when it comes to sash windows.

Our aluminium sash window has been tried and tested over many years and has been successfully installed in thousands of houses, flats and apartments where a replacement aluminium vertically sliding window is required.

Our window is regarded as the slimmest and most authentic looking aluminium sash window available in the UK today and comes with a host of features and specifications.

It is also suitable as a new window replacement for timber or PVCu sliding windows or where you simply desire sash windows in aluminium.

Slim 36mm meeting rail
New Sliding Sash windows are often scrutinised by planners and local authorities where they are intended to replace old timber windows.  One of these requirements is the meeting rail of a sash window. Our aluminium sash window offers the slimmest of meeting rails at only 36mm.  Not only does this slim rail provide a slimmer window giving a greater glass area, but it also results in improved window energy ratings.

Specifications of Aluminium Sliding Sash Windows

  • A high specification thermally broken frame using polyamide thermal breaks.  This gives the window a C rating.
  • 24mm glass using Diamant low iron glass, warm edge swisspacer with argon gas to the cavity and 4mm planitherm total plus soft coat glass to the inside pane. Toughened and decorative glass is available.
  • Where curved head windows are required, the profiles will curve to to a 500mm minimum radius.
  • A retractable parting bead replicates the detail of original box sash windows with sash balances completely concealed by specially designed balance covers.
  • The advantages of powder coated aluminium with over 200 colours available including satin, matt or gloss finishes.
  • Easy cleaning facility with tilt in sashes.
  • External putty line detail with authentic 45 degree chamfer found in old timber windows.
  • A choice of bottom rails with a 43mm slim rail or 90mm deep bottom rail.
  • Optional decorative sash horn.

To discuss our range of Vertical Sliding Windows options call:

01895 271 061