Weatherproofing is a main concern when it comes to door design


Our system has been tested at a accredited testing stations and passed weather tests to extreme weather conditions.

Our HD82 system has also been independently tested in accordance with USA hurricane standards upwards of 4000 Pascals (Pa)

Most systems on the market are weather tight, with high performance rubber seals and brush seals. However, there are some systems that have little or no seals at all. One crude but easy test is to close a folding door on to a sheet of paper and try to pull the paper out. If it pulls out easily there is not a watertight compression on the seals. 

EPDM (ethylene propylene diene monomer (M-class) rubber) gaskets are fitted as standard and used to seal the double glazed units into the panels and protect the door from water ingress. There are also EPDM (synthetic rubber) seals between each panel to prevent water, wind and noise from entering the property. The main properties of EPDM are its outstanding heat and weather resistance.

We use 2 rubber EPDM seals on each side of each panel and high performance seals on the top and bottom of the panel.

The system also includes a tongue and groove feature unique to our folding sliding door systems which:

  • prevents water infiltration

  • keeps the system stable with one panel interlocking with another ensuring that the integrity of the system remains intact whether the doors are opening inwards or opening outwards.

  • prevents attack by an intruder 

'Laboratory' tests for water ingress, wind resistance and air permeability

High performance rubber seals and brush seals

Our HD82 system has also been subjected to the demanding hurricane tests to achieve Florida Building Code Compliance. We achieved the highest ever pass rate for a UK folding sliding door, reaching 5160 pascals, equal to a 204mph wind.

Hurricane Standard Testing

Hurricane Testing - 5160 Pascals

UK Telephone: 0345 64 64 646

USA Telephone: 786 275 5068
Sales email:
Other enquiries:

The Folding Sliding Door Company is an ISO 9001 and (US) NAMI Quality Assured organisation with nationally recognised accreditations such as CE Compliancy and Document Q in the UK, and Florida Building Code in the US.

  • Facebook - Grey Circle
  • Twitter - Grey Circle
  • LinkedIn - Grey Circle
  • Instagram - Grey Circle
  • YouTube - Grey Circle
  • Houzz - Grey Circle
  • Pinterest - Grey Circle
  • G+ - Grey Circle
© 2001 - 2019 The Folding Sliding Door Company. All rights reserved.