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Thermoseal Group Limited has extensive experience in manufacturing and supplying premium products to the window industry.  We pride ourselves in producing our insulated glass components and glass machinery using customer insight.  Having worked closely with our customers for many years to trial products and gain feedback at every level of service, we have seen continual growth.


Founded in 1979

The business began manufacturing the first Hopper-fed Hot Melt Extruders.  From the outset, much of Thermoseal Group’s custom came from referral from manufacturers who appreciate a premium product produced with an insight into the insulated glass manufacturing process.  We still manufacture these machines to order.


Began Supplying IG Components

Having negotiated supply agreements with leading International Insulated Glass (IG) component manufacturers, Thermoseal Group became a UK distributor to manufacturers of double glazing units.  This became the Group’s core business with over 2,500 components now on offer from its 4 UK sites.


Purchased Perma Led Company

Thermoseal Group’s first component manufacturing venture was the purchase of this successful business making self adhesive Lead strip used for decorative glass units.  


Set up Injection Moulding Division

The first injection moulding machines were purchased to make the Group’s own bespoke corner keys and Georgian components.  This division has been a huge success and has grown with the business.  We now have 9 injection moulding machines running twenty four hours a day producing approximately 10 million mouldings per year, with a tenth machine arriving March 2019.


Warm Edge Spacer Manufacturing & Technical Centre Set Up

Following an extensive research and development project, we began manufacturing industry-leading spacers; Initially Thermobar Warm Edge Spacer Tube, closely followed by Thermoflex Warm Edge Spacer silicone rubber alternative – two different production methods – both highest performance spacers.  This came hand-in-hand with the set-up of our own Technical Centre and EN1279 test facility.


A Gear Up for Export

The Group invested significant additional funds to develop and increase its warm edge product range and capacity whilst developing its export team to pursue further International business.  We have a dedicated export team trained to ensure that we meet customer requirements for export to a worldwide customer base.


Won Multiple Awards

Her Majesty The Queen announced us winner of The Queens Award for Enterprise – International Trade 2017.  We also ranked no.41 in the 9th Annual Sunday Times HSBC International Track 200 League Table in the league of businesses with the fastest-growing International Sales.  Another prestigious award in 2017 was the 'Derek Bonnard Award for Excellence' which was nominated by the Industry at the Glass and Glazing Industry's G-Awards.  This followed an accolade of awards including: ‘Amazon Growing Business Award – Export Champion of the Year’; Wigan Business Award for Export’; EEF Future Manufacturing Award for North West Region for Export and ‘Component Supplier of the Year’ at the glass and glazing industry G-Awards two years in a row.  


Purchased DecraLed Stock and Assets

Following the purchase of all stock and assets of North Western Lead Company, we have made significant investments in a new state-of-the-art design studio to enable us to produce bespoke designs for our customers to incorporate into their own insulated glass products. Lead production has also seen significant investment to digitise, add tooling and update procustion which now allows us to electroplate and powder coat lead for a wide collection of colours and sizes. The DecraLed range now benefits from the full support and expertise of our Technical Centre.


Purchased Our New 2-Acre ‘Centre for Innovation and Manufacturing

Following the purchase of our new 2-acre warm edge production site in Wigan, we have invested significant additional funds in the extensive reconstruction of the building to accommodate a raft of new equipment to further automate and increase our Thermobar and Thermoflex Warm Edge Spacer production capacity.  We also have a new Technical Centre and EN1279 Test Centre with much more space and a wide range of additional equipment for product innovation and testing.


Further Awards for Manufacturing and Component Supply

Ranked no. 96 in the Sunday Times HSBC International Fast Track 200 and voted ‘Spacer Bar Manufacturer of the Year’ in the National Fenestration Awards for both 2020 and 2021. Thermoseal Group also won the Glass and Glazing industries G-Award for Best Component Supplier.


And the string of accolades continue!

Most recently, we won ‘Spacer Bar Company of the Year’ for the National Fenestration Awards 2022, for the third time in a row.
We are also delighted to announce that we were once again shortlisted for the highly-acclaimed G-awards ‘Component Supplier of the Year’.


New Industrial Unit in Wigan

We recently acquired a further industrial unit in Wigan, aimed to increase the production capabilities of our Thermobar and Thermoflex Warm Edge Spacers & Accessories. 


Going Greener

Our commitment to sustainability extends beyond energy-efficient products to efficient business operations.

We invested £140,000 into reusable metal stillages, aimed at reducing cardboard consumption.

Continuing to champion the recycling reels scheme, we collect and reuse bags, boxes, and reels. Our unique system has effectively diverted 80% of packaging from landfills.

The newly installed solar PV system in Wigan generates 420MW annually, supplying 15% of our power.

All sites now have electric charging points and we have recently purchased two electric forklifts for use in the Wigan Branch.

2024 promises further strides in our green initiatives.

Would you like to know more?

Thermoseal Group

Our business is dedicated to the manufacture and supply of highest performance components and machinery used in the manufacture of insulated glass. Our particular focus Is on the development of components designed to help meet the changing requirements for more thermally efficient windows. We are a multiple award-winning organisation with almost 40 years in the industry.

Latest News

Thermoseal Group Sold to Fenzi in Landmark Deal
Date Added 03/07/24

Thermoseal Group has been acquired by Fenzi Group Spa (Fenzi), a Milan-based chemical company specialising in glass processing solutions, in a deal... > More


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