Cavseal - Cavity Closing System

Like all Sheerframe from Synseal products, the profiles are calcium organic stabilized and are completely lead free and manufactured under the Environmental Standard EN ISO 14001.
The profiles can be mechanically jointed due to the unique corner moldings making it the fastest fit system on the market. For those fabricators wanting to weld the cavity closers The Litchfield Group can  supply designated weld blocks
The Sheerframe cavity closer system design ensures that the latest ACD requirements for a thermal resistance path to IP8/08 between window and cavity of 0.45m²K/W is achieved without the need for insulation


  • The  Sheerframe  cavity  closers  incorporates  an  clever  design  feature  of multiple  air  pockets  at  the  key  connection  between  window  and  closer.This sealed cavity insulated zone ensures  hat the latest ACD requirement for  a  minimum  thermal  resistance  path  to  IP8/08  between  window  and cavity of 0.45m²K/W is achieved which avoids cold bridging.
  • This  excellent  performance  is  achieved  without  the  need  for polyisocyanurate or expanded polystyrene foam inserts.
  • Apart from the reduction in time and materials achieved by this design it also means that recycling the closer at end of life is very easy as there are no incompatible materials linked together inside to be removed.
  • Sheerframe Cavity Closer is made entirely of recycled PVC saving valuable resources and is the simplest of all closers to recycle again.
  • Suitability  for  both  flush  and  checked  reveals.   To  prepare  it  for  checked reveals we have the clip-in adaptor NB021.
  • As  well  as  the  adaptor  for  checked  reveals  we  also  have  an  adaptor  for increasing the closer widths (NB176). This is a 25mm adaptor which clips easily into the closer and also clips into itself if you need 150mm overall.
  • The  cavity closer can be either fully welded or mechanically jointed at the corners.
  • We have created a fantastic corner moulding, which combines tremendous corner strength with a rapid assembly friction fit.


COMPONENTS (all dimensions in mm)


Sheerframe sub-frame Fabrication


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