SupaSlim is a double glazed unit specifically designed for timber window manufacturers looking to produce thinner, more discreet profile windows e.g. sash windows with glazing bars or specialist applications in conservation settings.

SupaSlim Double Glazed units are virtually indistinguishable from single pane glazing once puttied into a window. They are therefore eminently suitable for ‘conservation’ or ‘listed  buildings’ providing replica windows yet with all the benefits of modern insulated double glazing.

SupaSlim delivers savings in timber costs, installation, balancing and making good. Moreover, they comply with Building Regulations Document L for improved thermal insulation in the UK and Document J for Scotland. SupaSlim units incorporate the latest low E glass, warm edge technology and argon/krypton gas filling. Units are also BS EN 1279  compliant


  • Sightline – 7mm
  • Available in 4mm , 6mm and 8mm cavities , In a choice of Black or White warm edge bar
  • Minimum timber rebate depth – 8/9mm
  • Minimum timber rebate width – 19mm
  • Choose from Float, Toughened, Low Iron, Softcoat Low-E,  Patterned, Reproduction glass types
  • Gas filling – Air, Argon or Krypton
  • Can achieve U-Values as low as 1.2 W/m2k