Full Fill Built-in Insulation System Continuous wall insulation system that delivers ultimate thermal performance with the added assurance of protection from wind driven rain.

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Xtratherm offer an extensive range of technically enhanced rigid insulation products for commercial and industrial projects

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Tapered Roofing System
The XtraFall system provides a high performance precision solution to thermal insulation and water drainage on at roofs.

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The Xtratherm range of high performance insulation boards provides the ideal technically advanced solution for flat roof projects.

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Vacuum Insulated
Panels (VIP)

Insulation System
for Flat Roofs & Balconies

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PLATINUM SERVICE for Self Builders

PLATINUM SERVICE for Self Builders

Our Platinum Service offers full technical support and advice, helping you to achieve a cost effective, passive
standard new home.

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Sustainable insulation

This sustainable insulation range has a bio-enhanced, halogen-free formulation, with a more than 50% reduction in packaging where all plastic wrap is replaced with biodegradable film.

Full Fill Built-in Insulation System

Continuous wall insulation system that delivers ultimate thermal performance
with the added assurance of protection from wind driven rain.

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High Performance rigid extruded polystryrene


Insulation System for Flat Roofs & Balconies

XtraVIP Insulation System for Flat Roofs & Balconies is a rigid Vacuum Insulation Panel (VIP), consisting of a compressed, fumed, silica sand, microporous core which is evacuated of air and moisture before being
encased and sealed in a special thin, gas-tight, hybrid aluminium foil envelope. Encapsulated and protected within a robust two component elastomeric polyurea waterproof coating.


Xtratherm offers a cost effective solution for builders and specifiers for the closing of cavities around window and door openings, preventing cold bridging, damp penetration, air infiltration and condensation.

CavityTherm Accessories

PIR Insulation

Cavity Wall Plus Tongue & Groove Insulation

Partial Fill Cavity Wall

Applications:Partial / Wall

Cavity Wall Plus Tongue & Groove Insulation

Xtratherm Cavity Wall Plus XT/CWP (T&G) builds to a system thanks to its engineered tongue and grooved joints and pre-formed corners, ensuring insulation continuity and minimisation of thermal bridging. The Cavity Wall Plus tongue and groove jointing offers a practical on-site solution that results in a more robust continuous layer of insulation, minimising the threat of thermal bridging and improving the overall U-Value of the wall.

Why choose Xtratherm Cavity Wall Plus Tongue & Groove Insulation?

  • The lower Lambda of 0.021 W/mK improves U-values and meets Zero Carbon standards, proving an excellent choice for passive and low energy builds
  • The Xtratherm Cavity Wall System includes an optional pre-formed corner panel that folds to 90 degrees to effectively insulate a junction that is normally vulnerable to thermal bridging and cold spots.
  • The low emissivity foil facing on the boards improves the thermal performance of the wall.
  • Cavity Wall Plus (T&G) is the best solution when building traditional masonry walls to the highest thermal standards whilst maintaining a residual cavity, offering excellent protection from wind driven rain.
An illustration of Xtratherm Cavity Wall Plus Tongue & Groove Insulation showing the continuity that prevents thermal bridging

U-Value calculations to EN ISO:6946
XT/CWP Cavity Wall Partial Fill

Block Lambda 40mm 50mm 60mm 70mm 80mm 100 mm
0.11 0.27 0.24 0.21 0.20 0.18 0.15
0.15 0.28 0.25 0.22 0.20 0.18 0.16
0.46 - 0.27 0.24 0.22 0.20 0.17
1.13 - 0.28 0.25 0.22 0.20 0.17

U-Values achieved with additional Xtratherm XT/TL Thermal Liner

Thickness Block Lambda Original U-Value Table 1 Improved U-Value with XT/TL
60mm 0.11 0.21 0.16
70mm 0.15 0.20 0.15
80mm 0.46 0.20 0.15
100mm 1.13 0.17 0.13

* XT/TL 50mm Thermal Liner consisting of 38mm PIR and 12.5mm plasterboard on adhesive dabs

Product Downloads

Product Range

Thin-R Plus is an enhanced PIR Insulation with a Lambda Value as Low as 0.021 W/mK. It is available with engineered Jointing to provide continuity and reduce Thermal Bridging.

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Key Points

  • Improved Lambda Value of 0.021 W/mK
  • Robust Tongue & Groove Jointing
  • Corner Panels & Cavity Closers: Reduced Thermal Bridging
  • Clear Cavity Maintained
  • No Exposure Restrictions

Xtratherm reserves the right to change this information without notice.
Xtratherm accepts no responsibility for errors or omissions on the website.

Do you have any questions?

Talk to the team who can help you with your project

Our Technical Team provides technical services throughout our customer bases in Ireland & UK. Their experience and expertise has been built through our engagement and participation with the Irish construction industry for over 30 years.

Certified Technical Knowledge.

Solutions you can trust.

Call The Technical Team:
Tel +44 (0) 371 222 1055
Tel +353 (0) 46 906 6050

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