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100mm CT/PIR CavityTherm Thin-R Full Fill Cavity Insulation ǀ pack of 4

100mm Xtratherm CT/PIR CavityTherm Thin-R Full Fill Cavity Wall PIR Rigid Insulation Board - pack of 4
100mm Xtratherm CT/PIR CavityTherm Thin-R Full Fill Cavity Wall PIR Rigid Insulation Board - pack of 4
100mm Xtratherm CT/PIR CavityTherm Thin-R Full Fill Cavity Wall PIR Rigid Insulation Board - pack of 4
100mm Xtratherm CT/PIR CavityTherm Thin-R Full Fill Cavity Wall PIR Rigid Insulation Board - pack of 4
100mm CT/PIR CavityTherm Thin-R Full Fill Cavity Insulation ǀ pack of 4
  • BBA Certification No. 10/4786.
  • Board coverage : 0.54m2
  • Pack coverage: 2.16m2
  • R-Value:  4.52m2K/W
  • Thermal Conductivity: 0.021 W/mk
Estimated delivery:
In Stock
£ 159.12
Ex VAT: £ 132.60
  • Brand: Xtratherm®
  • Model: 100mm CT/PIR
  • Weight: 6.70kg
  • Dimensions: 1,200mm x 450mm x 100mm
  • SKU: 100mm
  • Product code: P1-282
  • MPN: 100mm CT/PIR Cavity-Therm

Options available

100mm Xtratherm CT/PIR CavityTherm Thin-R is a cost effective rigid PIR (polyisocyanurate) thermal insulation board used for traditional full fill cavity walls to provide excellent U-Values and meet the Passive House standards.

Xtratherm CT/PIR Cavity Wall insulation is a top-class composite board of enhanced performance rigid foam core with a lambda value as low as 0.021W/mK.

CavityTherm's unique engineered profiled facing directs any moisture that might penetrate the external wall down the protective facing and back onto the external leaf. 

The board includes specifically designed rebated edge detailing on all four edges to allow the system to tightly interlock when installed.

Fully engineered jointing of the insulation layer, with the addition of bespoke ancillary pieces to insulate effectively around services such as hockey sticks, meter boxes and corner details.

CT/PIR is proven to provide the most cost effective answer not only reaching Zero Carbon U-Values but, also achieving Thermal Bridging targets.

Xtratherm CavityTherm 1200mm x 450mm board when installed is giving added protection from wind driven rain.




Thickness: 100mm

Size: 1200mm x 450mm

Board coverage: 0.54m2

Pack coverage: 2.16m2

Density (Foam Core): 30Kg/m3

Weight: approx. 6.7kg

Thermal Conductivity: 0.021 W/mk

R-Value: 4.52m2K/W

Commpressive Strength: >100 (kPa)

Water Vapour Resistivity: >100 MNs/gm

Surface spread of flame: Class 1

Service Temperature: -20 to +100 (°C)


What is the real benefit using Xtratherm CT/PIR CavityTherm?

U-Values achieved by placing CavityTherm into your standard 150mm cavity meets the Passive House standards. 

It’s a very practical, affordable solution to low energy design.

It builds as a ‘system to ensure continuity.


What thicknesses of Xtratherm CT/PIR CavityTherm are available?

Xtratherm CT/PIR CavityTherm is manufactured for 100mm,125mm and 150mm cavities, and achieves U-Values as low as to 0.12 W/m2K. 


Specifying Xtratherm is a real commitment to minimising energy consumption, harmful CO2 emissions and their impact on the environment. 

Using our products is one of the most effective ways to reduce energy consumption – in fact, after just eight months the energy they save far outweighs the energy used in their production.

In addition, our manufacturing facilities operate to an ISO certified Environmental Management System.


All Xtratherm Insulation products use CFC-and HCFC-free materials, and are manufactured using a blowing agent with a low GWP and zero ODP.


Key Points:

 · Engineered HIPs facer provides wind driven rain protection

 · Moisture redirected to outer surface

 · Prepositioned slots for sloping wall ties - no creep

 · Fully engineered jointing

 · Full range of accessory pieces build continuous system

 · Excellent Thermal Bridging Values



 · BBA Certification No. 10/. Issue date: 31 March

 · BS EN ISO Quality Management System

 · BS EN ISO Environmental Management System


*Further information may be found in our Downloads section.

Fairly easy access to all PDF files.

Datasheet ǀ Declaration of Performance - DoP ǀ BBA Certificate ǀ Installation Guide ǀ Certificates ǀ Brochure ǀ SPEC Sheet 


*Special Product - Non returnable cancelable.

Board covarage 2.16 m2
Commpressive Strength 100 (kPa)
Density 30Kg/m3
Length 1200mm
Material Polyisocyanurate (PIR)
Profile Unique engineered profiled facing
R-Value 4.52m2K/W
Size 1200mm x 450mm
Surface spread of flame Class 1
Thermal Conductivity 0.021 W/mk
Thickness 100mm
Water Vapour Resistivity 100 MNs/gm
Weight approx. 6.7kg
Width 450mm
Vapour Resistivity 100 MNs/gm
Shipping method Articulated Vehicle ǀ Courier
Applications Cavities ǀ External Walls
BBA Certified Yes (No. 10/4786)
ETA Notification Yes
Features Excellent U-Values ǀ Passive House
Manufacturer Xtratherm CavityTherm®

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We deliver insulation materials to Mainland UK only. Deliveries to Highlands, Northern Ireland, Isle of Wight etc.. might be possible at additional cost.
We offer free delivery on most of the orders above £300 (excluding VAT) (except special products - shipping cost via courier - products marked ''Request A Quote'')

Delivery of some insulation materials might be extended due to the current situation (Covid-19, stock shortages, allocations).
If you need materials quickly please contact us - we will do our best to help you source materials needed.

We do not deliver on weekends and bank holidays. Sometimes we can deliver on Saturdays - please check with us before placing the order.
If you need any further information please contact us tel. 02081910776

We can help to calculate price per m2 or linear meter (one meter in length) cost, please just contact us via phone 02081910776, email or live chat. Alternatively, you can work it out yourself quickly and easily: to get cost per meter square please divide price shown in orange area by ''Required area (m2)'' Example price of £28.80 divided by board coverage 2.88m2 = cost of £10.00 per m2.


No matter whether you choose a local installer or a national company, there’s a few tips to help you find the right installer for your home insulation improvements, such as asking for recommendations and making sure that they’re part of a certification scheme. This makes sure that they have the right skills and standards of workmanship to carry out the installation, and you can be sure that they know exactly what they are doing.


1. Thermal inspection picture in portfolio

It’s worth seeing a installer’s previous work. There’s no harm asking if you can see any properties nearby that they’ve installed insulation in. Best way would be to see Infrared Thermal Imaging Inspections. Thermal cameras spot small, but key changes in temperature in different areas of a house, identifying problematic areas that the human eye never could and some that a visual inspection could only hypothesize.

2. Reviews

Along with checking recommendations and previous work, finding reviews online can often be a great way to find out if they provide a good service or not. However, it’s best not to solely rely on reviews you may find or review websites, as there’s no controlling who writes them.

3. Compare prices

Comparing prices will also ensure companies can’t take advantage of you and give you a fair price. 

4. Word of Mouth

The best way to find a great insulation installer is through recommendations. Make sure you ask friends and family. They will most likely give you their honest opinion and can tell you from first hand experience.


Whether you require a wall, cladding, external wall, loft or floor insulation fitted, you can find and hire your local insulation installers from popular UK web pages. A simple internet search will return thousands of potential installers near your area.



We are the stockist of construction materials and related products for both trade and DIY from most recognizable brands in the UK like Cordek, RCM, Promat, Rockwool, Isover, Celotex, Xtratherm, Ursa, Low-E, Cedral, Kingspan, Dufaylite, British Gypsum, K-rend, Ecotherm, Iko enertherm, Kay-Metzeler, Terrawool to allow you to complete your insulation job on time at competitive prices and the highest standards.


Whether you are a large company or a DIYer, if you need a large amount of insulation materials, we can offer quantity discounts at the best prices. Please contact us and our friendly customer service will try to find the best and cheapest solutions for you. We value your time and we will try to deliver the products as soon as possible at a reasonable price to your construction site or house. The UK's leading insulation supplier near you and your needs. Price List available upon request.
100mm Xtratherm CT/PIR CavityTherm Thin-R Full Fill Cavity Wall PIR Rigid Insulation Board - pack of 4
100mm CT/PIR CavityTherm Thin-R Full Fill Cavity Insulation ǀ pack of 4
£ 159.12