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25mm FR/ALU Xtratherm Thin-R PIR Flat Roof Insulation Board ǀ pack of 12

25mm Xtratherm FR/ALU Flat Roof PIR Insulation Board - Single Ply Waterproofing Systems
25mm FR/ALU Xtratherm Thin-R PIR Flat Roof Insulation Board ǀ pack of 12
  • BBA Certification No. 11/4817
  • Vapour resistant foil facers
  • Loose laid ballasted systems
  • Thermal Conductivity: 0.022W/mK
  • Compatible with mechanically fixed single ply systems
Estimated delivery:
In Stock
£ 705.38
Ex VAT: £ 587.82
  • Brand: Xtratherm®
  • Model: 25mm FR/ALU
  • Dimensions: 2,400mm x 1,200mm x 25mm
  • SKU: 25mm
  • Product code: P1-1045
  • MPN: 25mm Xtratherm FR/ALU Thin-R

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25mm Xtratherm FR/ALU Flat Roof PIR Insulation Board Thin-R is a top-class polyisocyanurate foam core insulation board with vapour resistant gas-tight foil facers suitable for loose laid ballasted and mechanically fixed single ply waterproofing systems.

Thin-R FR/ALU is a thermally efficient roofing board with a certified thermal conductivity (λ - lambda value) of 0.022W/mK.

Xtratherm PIR insulation boards are stable, rot proof and will remain effective for the life span of the building (depending on specification and installation).

Thin-R provides the most efficient U-values with minimal intrusion into valuable living space.

FR/ALU can reduce heat loss and save money on energy bills (provides excellent thermal bridging details).

Care should be taken to avoid contact with acids, petrol, alkalis and mineral oil, when contact is made, clean materials in a safe manner before installation.

Thin-R insulation foam core and composite gas-tight foil facings resist attack by mould, fungi, bacteria and microbial growth.

Xtratherm FR/ALU foil faced insulation boards are suitable for use on roof decks that are subject to maintenance traffic.

Walkways should be provided on roofs requiring regular pedestrian access. 

When the roof is complete, protective boarding should be laid if additional site work is to be carried out. 

The completed roof should not be used for storage of heavy materials or an air conditioning plant.




Width: 1200mm

Length: 2400mm

Pack Quantity: 12

Pack Coverage: 34.56m2

Board Coverage: 2.88m2

Profile: Square Edge

R-Value: 1.125m2K/W

Density (Foam Core): 32kg/m3 

Thermal Conductivity: 0.022W/mK

Compressive Strength: >150 (kPa)


Key points:

 · BBA certified.

 · High thermal performance.

 · Easy to handle and install.

 · Vapour resistant foil facers.

 · High compressive strength >150 kPa.

 · Standard sheets size - 2.4m x 1.2m (8 x 4).

 · Compatible with mechanically fixed single ply systems. 

 · Faced with composite gas-tight foil.

 · Suitable for loose laid ballasted systems.

 · Excellent thermal conductivity (λ - lambda value) 0.022W/mK.



 · Xtratherm FR/ALU insulation boards should be laid over the vapour control layer in a break bonded pattern. 

 · The long edges of the boards should be laid at right angles to the corrugations and all board joints must be fully supported by the deck. 

 · The FR/ALU insulation boards are secured by approved mechanical fixings.

 · The requirement for a separate water vapour control layer should be assessed in accordance with BS 6229. 

 · Typically a 1000 gauge polythene should be used with all joints lapped and sealed. 

 · Any fixings that penetrate it must be of the self sealing type that fuses to the vapour control layer during application.

 · FR/ALU is not suitable for applications with built-up bitumen based roofing or mastic asphalt systems.


Certification and standards:

 · BBA Certification No. 11/4817. 

 · BS EN ISO 9001 Quality Management System.

 · BS EN ISO 14001 Environmental Management System.


*For comprehensive calculations on all deck types, please contact Xtratherm Technical Support.

*Thermal conductivity is dependent on facings and product thickness.


*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 34.56 m2
Colour Light yellow
Length 2400mm
Material Polyisocyanurate (PIR)
Pack Coverage 34.56m2
Pack Quantity 12
Profile Square Edge
R-Value 1.125m2K/W
Thermal Conductivity 0.022W/mK
Thickness 25mm
Width 1200mm
Coverage 2.88m2
Finish Vapour resistant gas-tight foil
Quantity 12
Shipping method Articulated Vehicle ǀ Courier
Applications Flat Roof Systems ǀ Roofing
BBA Certified Yes (No. 11/4817)
ETA Notification Yes
Features Gas-tight foil facers ǀ Vapour resistant
Manufacturer Xtratherm Thin-R®

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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.
25mm Xtratherm FR/ALU Flat Roof PIR Insulation Board - Single Ply Waterproofing Systems
25mm FR/ALU Xtratherm Thin-R PIR Flat Roof Insulation Board ǀ pack of 12
£ 705.38