• They comply with Building Regulations Document L England for improved thermal insulation.
  • The 4mm perimeter seal of Slender Fit Double Glazed Units enables them to be glazed into 7mm deep glazing back rebates found in most sash windows.
  • The smaller cavities between the glass reduce the required glazing width rebates and enables slimmer sections to be used.
  • They are the only double glazed units that can be glazed into most standard glazing bars of a sash window.
  • They can be glazed into most existing single glazing glass rebates.