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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Developers and their design and certification team can rely on the expertise and professional support of the whole Xtratherm Team - it is not just about buying insulation products.

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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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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


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

detailing accessories

PIR Insulation


Partial Fill Cavity Wall

Applications:Partial / Wall


Thin-R Partial Fill Cavity Wall Plus XT/CWP (T&G) builds to a system thanks to it's engineered tongue and grooved joints and pre-formed corners, ensuring insulation continuity and minimisation of thermal bridging.

XT/CWP (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. 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.

Xtratherm also supply cavity closers suitable for use for Cavity Wall Plus. Click here for more information.

XTCWP Corner

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 a high performance foil faced Polyisocyanurate (PIR) insulation with a certified conductivity as Low as 0.021 W/mK. It is available with engineered jointing to provide improved 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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