Structural External Wall Insulation

Structural External Wall Insulation | Our Unique System

Structherm the Non-Traditional Housing Refurbishment Experts...

Structherm are the number one experts in the UK when it comes to the external refurbishment of non-traditional properties.

Approximately 1.5 million properties in the UK were built using non-traditional methods following the First and Second World Wars and up until the late 1960s. 

Homes were built at a time when skilled labour was in short supply as were traditional building materials, and most were only designed to last 20 years.

People today are still living in these properties which have very little, if any, insulation and worse many are designated as DEFECTIVE by the Building Research Establishment (BRE). Also built were many high rise blocks of flats particularily in major cities, again these were often built from non-traditional materials such as Wimpey No-fines concrete and with very little regard for thermal performance.

The unique Structherm Structural External Wall Insulation (SEWI) system is a cost effective method of extending the life of these non-traditional defective properties, both low rise and high rise. It provides a rigid, structurally continuous envelope around the building with a render finish and is a real alternative to demolition.
The construction of the unique panels used in the system is based on a core of rigid insulation set within a steel “cage”. The panels are immensely strong and rigid, yet lightweight (easily handled by one man) and can be installed vertically or horizontally. The diagram below shows a typical build up of the Structural External Wall Insulation system.

The Structherm Structural External Wall Insulation system has been used on the following non-traditional steel framed, timber framed and concrete houses:
Airey BISF Boswell Calder
Cornish Cussins Easiform Orlit
Reema  Smiths Swedish Timber  Tarran 
Unity  Wates  Wimpey No-fines  Cruden Rural 
Dorman Long  Dorlonco  Vic Hallam Boots 
Weir Timber Crosswall  Newland  Arcal 
Lowton Cubitt  Weir Multicom  Concrete Block  Hawksley 
Smiths  Stent  Trusteel  Lawrence 
Dorran  Atholl Steel  Mowlem  Kencast 

Airey concrete property with SEWI installed.                            BISF steel property with SEWI installed.
  PreviewConcrete framed property with Structural External Wall Insulation (SEWI) panel installed.

  • Full external wall insulation cladding of defective low and high rise buildings (reduces need for difficult remedial work)
  • Full external wall insulation over-cladding of defective or inefficient system built structures (improving structural safety and thermal continuity)
  • Re-configuration of building facades to reduce or enlarge glazed areas (modifying solar gain, heat loss and glare)
  • Enclosing balconies and walkways (converting external space into usable internal floor area)
  • Forming new or extending existing parapets (improving safety at roof level)

The illustration below shows the typical fixing method for Structural External Wall Insulation on to high rise buildings.

Structural External Wall Insulation high rise installation

The Structural External Wall Insulation system is ideal for use in the following sectors:

Features & Benefits:

  • Excellent impact resistance of 10N/m compared to other External Wall Insulation systems.
  • Due to external application, residents are able to stay in their homes with minimal disruption to their lives.
  • Excellent strength to weight ratio.
  • Large spans can be achieved due to an extremely high flexural capacity.
  • Existing foundations do not need to be modified due to the low mass of the panel.
  • Structural components all have a typical assessed minimum life of 30 years plus.
  • The system offers very good resistance to the vertical spread of fire and the BBA certificate confirms a 30-minute resistance

Quality Assurance:

Our Structural External Wall Insulation systems carry a full warranty. They are BBA approved with a minimum 30 year design life, and are fully patented.
Every project has an individual quality assurance procedure, supported by:
  • BS EN ISO 9001:2015
  • Professional indemnity insurance
  • Product guarantee insurance

Featured Project

Nitshill Refurbishment

Within their stock GHA has over 300 Crosswall properties in the Nitshill area of Glasgow. GHA identified 60 of these for the first phase of refurbishment. These properties were showing signs of movement with excessive cracking and water penetration, they also had extremely poor thermal performance..


Structherm have made another significant step forward in a £2.4m contract in Durham

Always at the forefront in the development of external wall insulation, Structherm have made another significant step forward in a £2.4m contract in Durham.