Why Does My Celotex Insulation Say Soprema? The Complete 2026 Rebrand Guide

Is Sopratherm the Same as Celotex?
Yes, Sopratherm (by Soprema UK) is the new brand name for the Celotex product range following Soprema’s acquisition of the company. The product itself remains identical – same specification, same performance, same quality. From 1st January 2026, all Celotex products have been rebranded under the Soprema UK umbrella, with most products now carrying the Sopratherm name.
If you’ve ordered Celotex GA4000 insulation and received boards labelled “Sopratherm GA4000”, don’t worry – it’s exactly the same product you’ve always relied on, just with updated branding.

Celotex to Sopratherm Transition Guide
Below is the complete mapping of legacy Celotex product names to their new Sopratherm equivalents. The product codes in the right-hand column are what you’ll see on deliveries from January 2026 onwards.
GA Range
| Legacy Name | New Sopratherm Name |
| Celotex GA4100 | SOPRATHERM GA4100 |
| Celotex GA4090 | SOPRATHERM GA4090 |
| Celotex GA4080 | SOPRATHERM GA4080 |
| Celotex GA4075 | SOPRATHERM GA4075 |
| Celotex GA4070 | SOPRATHERM GA4070 |
| Celotex GA4060 | SOPRATHERM GA4060 |
| Celotex GA4050 | SOPRATHERM GA4050 |
TB Range
| Legacy Name | New Sopratherm Name |
| Celotex TB4040 | SOPRATHERM TB4040 |
| Celotex TB4035 | SOPRATHERM TB4035 |
| Celotex TB4030 | SOPRATHERM TB4030 |
| Celotex TB4025 | SOPRATHERM TB4025 |
| Celotex TB4020 | SOPRATHERM TB4020 |
XR Range
| Legacy Name | New Sopratherm Name |
| Celotex XR4200 | SOPRATHERM XR4200 |
| Celotex XR4165 | SOPRATHERM XR4165 |
| Celotex XR4150 | SOPRATHERM XR4150 |
| Celotex XR4140 | SOPRATHERM XR4140 |
| Celotex XR4130 | SOPRATHERM XR4130 |
| Celotex XR4125 | SOPRATHERM XR4125 |
| Celotex XR4120 | SOPRATHERM XR4120 |
| Celotex XR4110 | SOPRATHERM XR4110 |
PL Range
| Legacy Name | New Sopratherm Name |
| Celotex PL4065 | SOPRATHERM PL4065 |
| Celotex PL4060 | SOPRATHERM PL4060 |
| Celotex PL4050 | SOPRATHERM PL4050 |
| Celotex PL4040 | SOPRATHERM PL4040 |
| Celotex PL4025 | SOPRATHERM PL4025 |
CW Range
| Legacy Name | New Sopratherm Name |
| Celotex CW4100 | SOPRATHERM CW4100 |
| Celotex CW4085 | SOPRATHERM CW4085 |
| Celotex CW4080 | SOPRATHERM CW4080 |
| Celotex CW4075 | SOPRATHERM CW4075 |
| Celotex CW4070 | SOPRATHERM CW4070 |
| Celotex CW4060 | SOPRATHERM CW4060 |
| Celotex CW4050 | SOPRATHERM CW4050 |
| Celotex CW4040 | SOPRATHERM CW4040 |
Thermaclass Cavity Wall Range
| Legacy Name | New Brand Name |
| Thermaclass TC1090 | THERMACLASS TC1090 Cavity Wall 21 |
| Thermaclass TC1115 | THERMACLASS TC1115 Cavity Wall 21 |
| Thermaclass TC1140 | THERMACLASS TC1115 Cavity Wall 21 |
CW FF Range
| Legacy Name | New Sopratherm Name |
| Celotex CW4090FF | SOPRATHERM CW4090 FF |
| Celotex CW4115FF | SOPRATHERM CW4115 FF |
| Celotex CW4140FF | SOPRATHERM CW4140 FF |
Technical Specifications: What Hasn’t Changed
The rebrand is purely cosmetic. All technical specifications, performance values, and certifications remain unchanged:
- Lambda values – The thermal conductivity of 0.022 W/mK remains the same across all products
- BBA certifications – All existing British Board of Agrément certificates have transferred to Soprema UK
- Fire ratings – Products maintain their fire classification (Class 0, Class 1, or Euroclass ratings)
- Board dimensions – Sizes remain identical (1200 x 2400mm for most products, 1200 x 450mm for cavity wall boards)
- Manufacturing standards – Products are manufactured to the same exacting standards at the same UK facilities
- Warranty terms – Existing product warranties and guarantees continue under Soprema UK
The only difference you’ll notice is the branding on the product facings and packaging. The silver foil facings that characterised Celotex products remain, but now feature Soprema UK and Sopratherm branding.
Why Has Celotex Rebranded to Sopratherm?
In 2024, Soprema acquired Celotex from Saint-Gobain as part of a strategic expansion of its UK building envelope solutions portfolio. Soprema had previously acquired YBS Insulation (2022) and Chesterfelt (2023), and the 1st January 2026 rebrand represents the unification of these brands under a single identity.
Soprema UK Managing Director Laurent Verheyden stated that the brand unification brings together “over a century of expertise” and creates “a single access point for all customer needs”. The move aims to streamline customer experience whilst maintaining the premium performance that construction professionals expect.
Soprema is a global leader in waterproofing and insulation solutions with over 100 years of manufacturing heritage. The company provides an extensive range of products including bitumen and single-ply roofing membranes, liquid waterproofing systems, acoustic and thermal insulation, and civil engineering solutions.
Installation and Handling: Everything Stays the Same
If you’ve been working with Celotex products, you can continue using exactly the same installation methods with Sopratherm boards:
- Cutting – Use the same tools (insulation saws, Stanley knives) and techniques
- Fixing – Mechanical fixings, adhesives, and tapes specified for Celotex products work identically with Sopratherm
- Jointing – Recommended taping and sealing methods remain unchanged
- Storage – Keep boards dry and flat, stored on their edges where possible
- Handling – Standard manual handling practices apply – boards remain lightweight and easy to manoeuvre
The only practical change is that when you specify products in quotes or place orders, you’ll need to use the new Sopratherm product names shown in the tables above.
Where to Buy Sopratherm Products
You can continue to buy Sopratherm products (formerly Celotex) directly from authorised distributors and retailers across the UK.
At Online Insulation, we stock the full range of Sopratherm insulation boards, including the GA, TB, XR, PL, and CW ranges. For now, we’ve kept the Celotex branding and naming.
Whether you’re insulating walls, roofs, floors, or cavity walls, the Celotex/Sopratherm range offers the same trusted performance you’ve relied on from Celotex for decades.
Summary: New Name, Same Insulation
The Celotex to Sopratherm transition is straightforward:
- Products are identical – same specifications, same performance, same quality
- Technical certifications remain valid – BBA approvals, fire ratings, and lambda values unchanged
- Installation methods stay the same – no changes to cutting, fixing, or jointing techniques
- New branding only – Sopratherm branding replaces Celotex on boards and packaging
- Parent company change – All products now supplied by Soprema UK Ltd
For builders, installers, and contractors, this is purely a brand name change. Your projects can continue without disruption, and you can order Sopratherm products with complete confidence that you’re getting the same trusted insulation that’s been specified on thousands of UK construction projects.























