Galvanizing and metal finishing services
Supatherm | Thermally Broken Steel Lintels

Supatherm | Thermally Broken Steel Lintels

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Reduce carbon emissions and deliver energy efficiency without compromising on design.

What are  Supatherm thermally broken steel lintels? 

In the bid to meet with building regulations, the most obvious energy efficiency solution is to add additional insulation or triple glazing. But did you know you can achieve significant fabric savings simply through your choice of lintel?

Supatherm lintels  are thermally broken lintels that can improve the Dwelling Fabric Energy Efficiency (DFEE) by up to 3% and the overall Dwelling Emission rate (DER) by over 1%* (Based on a typical detached, semi-detached or terraced property)

Due to its unique production and assembly system, Supatherm provides an effective solution without impacting on complex designs such as apex windows or arches. 

What are the benefits of Supatherm thermally broken lintels? 

When more significant fabric savings are needed, our Supatherm range of lintels can reduce heat loss by up to 80% when compared with a standard cavity wall lintel. Based on a typical detached, semi-detached, or terraced property, Supatherm lintels can improve the Dwelling Fabric Energy Efficiency (DFEE) by up to 3%, and the overall Dwelling Emission Rate (DER) by over 1%.



Length Range Psi Value*W/mK
ST90  750-1050 0.098-0.057
1200-1350 0.053-0.048
1500-1650 0.043-0.039
1800-2100 0.06-0.052
2250-2400 0.048-0.043
2550 0.039
2700-3000 0.055-0.051
3300-3900 0.037-0.031
ST90HD 1800 0.04
ST90HDX 1800 0.043
* Actual calculated values based on 100mm cavity, full fill insulation. Block = 0.45.


Why choose Supatherm? 

  • Up to 80% reduction in heat loss compared with standard cavity wall lintels
  • High levels of insulation achieve a far superior PSI value.
  • Hot-Dip Galvanized coating to EN1461 as standard
  • Options to suit all types of masonry and wall construction 
  • All parts and assemblies CE marked to BS EN 845-2
  • To suit cavity widths from 90 to 150mm 
  • Lengths available from 750 to 3900mm 
  • Standard duty, heavy duty and extra heavy duty versions are available 
  • Avoids propping associated with single leaf lintels 



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Supatherm PSI Calculator for Thermally Broken Lintels

Products in Our Range

Part of the Birtley Group

Birtley began life as Birtley Building Products in 1965, based at the current site in County Durham. Originally a steel fabricator for the area’s mining and power generation industries, the company made its first steel lintels in 1967. Since then, Birtley has grown from reliable local supplier to a UK-wide force in construction design technology and product development.

In 1889, the British Metal Expansion Company was established in Hartlepool. It had sole European rights for the manufacture of expanded metal mesh, mainly for use as reinforcement and lath in the rapidly expanding sector of concrete construction. The business that grew from these early days later changed its name to Expamet.

Acquired by Birtley Group in 2015, Bowater Doors is a nationally-known name synonymous with top quality and imaginative composite residential door design and manufacture.

The product portfolio offers exclusive ranges for trade installers and a retail range providing doors direct to consumer and social housing organisations.

Birtley Galvanizing boasts one of the most impressive galvanizing plants in Europe. The plant achieves the finest quality hot-dip galvanized zinc protective coatings to BS EN ISO 1461. Using state-of-the-art technology the plant processes steel products using a computer controlled, automated handling system, enabling Birtley Galvanizing to provide full project solutions to many industries.