Celotex Insulation

Celotex insulation is the leading manufacturer multi-purpose insulation boards that provides solutions for cold spots in walls, floors, roofs, cavities and many more areas. These cold spots are usually created by a lack of insulation, leading to dampness and condensation. This is where Celotex insulation comes in.

We stock popular Celotex insulation ranges, including GA4000, TB4000, XR4000, PL4000 and CW4000, and can help you find the wall insulation, floor insulation, roof insulation or cavity insulation that you require. 

We offer Celotex insulation boards that can cover between 2.88m² and 25.92m², with thicknesses between 12mm and 200mm so you’re sure to find the right product for your application. These boards are cost-effective, lightweight, strong and easy to install, making them a popular insulation choice.

Celotex insulation is manufactured from tough polyisocyanurate (PIR), using a perfect mix of certain blowing agents, which acquires zero Ozone Depletion Potential (zero ODP) and a low global warming impact. This makes it great for the environment, as well as for your heating and cooling costs, as it has a thermal conductivity of 0.022W/mK. 

Celotex has achieved an A+ rating when it is compared to the BRE Green Guide and has certification from BBA. The Celotex insulation boards also have a good reaction to fire when measured in accordance with new European standards. It achieves the required U-values and will help you to meet current and future Building Regulations.

All Celotex products are readily available from Insulation4less with lead times of 3 to 5 days. If you need any help deciding on the right Celotex insulation for your project, get in touch with our team on 020 3582 6399 or via our Live Chat .

Celotex Crown-Fix Flat Roof PIR Insulation 2.7m x 25m - All Sizes
Celotex Crown-Fix Flat Roof PIR Insulation 2.7m x 25m - All Sizes All Insulation
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from £857.06 £1,028.47
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from £857.06 £1,028.47
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Celotex Crown-Up Flat Roof PIR Insulation - All Sizes
Celotex Crown-Up Flat Roof PIR Insulation 1.5m x 12.20m - All Sizes All Insulation
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from £613.35 £736.02
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from £613.35 £736.02
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Celotex Insulation board is a multi-purpose insulation board that provides solutions to overcome cold spots in walls/floors/roofs/cavities and much more. Cold spots can be created from the lack of insulation in some areas which can cause damp to appear on walls or condensation. Celotex insulation boards consists of foil facings on both sides.




Celotex is pir insulation with two foil facings on the outsides. It has been manufactured from tough polyisocyanurate PIR by using a perfect mix of certain blowing agents which acquires zero ozone depletion potential (zero ODP) and a low global warming potential. In other words, this product is easy on the environment and will keep your home warm for many years after it is installed. Thus saving on your heating and cooling costs.




Celotex boards can be used in many different applications. We will list just some of the applications this insulation board is most used for today below.

  1. Subfloor applications
  2. First floor in between ceiling joists
  3. Attic space between ceiling joists
  4. Roof space cut between rafters
  5. Basement internal walls
  6. Crawlspaces under suspended floors
  7. Timber frame construction on internal and external walls
  8. Masonry construction on internal and external walls
  9. Steel framed construction on internal and external walls

Of course, this is not an exhaustive list of applications for this product. There are many more applications in which we have seen these products used in such as caravans, campervans, industrial uses such as oil refineries, tunnels, trains, buses and so much more. So if you think you may not be able to use Celotex in a certain application think again and call us.




Celotex thicknesses goes from 12mm right up to 200mm with various different product codes for different applications. Below we will outline some of them.


TB4000 Range: TB4012, TB4020, TB4025, TB4030, TB4040

GA4000 Range: GA4050, GA4060, GA4070, GA4075, GA4080, GA4090, GA4100 ( Celotex 100mm)

XR4000 Range: XR4110, XR4120, XR4130, XR4140, XR4150, XR200

PL4000 Range: PL4015, PL4025, PL4040, PL4050, PL4060

CW4000 Range: CW4050, CW4060, CW4075, CW4085, CW4100


All the above products are readily available with Insulation4less with 3 - 5 day lead times.


Celotex is a high performing multi purpose insulation board that is environmental-friendly. It certainly helps in reducing the excessive and unnecessary usage of energy and resources like the use of gas or oil-fired boilers within the home. Thus reducing your carbon footprint over many years. In warmer climates, it will also reduce the need for air conditioning units by keeping the heat out and the cold in. It is designed to eliminate cold spots and has an excellent performance in timber frame and masonry walls. It features a thermal conductivity of 0.022W/mK for providing better insulation.


Celotex's Benefits and cost savings:


Celotex provides reliable and long-term energy-saving solution for buildings of all shapes and sizes, which ultimately results in low-cost electricity and heating bills. It is suitable in numerous applications such as roof, floor, walls, basements and attics. It is ideal for overcoming thermal bridging. It achieves the required U-values with minimum thickness with ease. It is often used as thermal insulation for floor systems, and flat roofs. It also helps in meeting the current as well as future requirements of the Building Regulations.


Celotex Insulation Board Certifications:


Celotex has achieved A+ rating when it is compared to BRE Green Guide and has certification from BBA certificate number 95/3197 and 09/4667.


The A+ rating is for all Celotex Insulation solutions within its range. Including TB4000, GA4000 and XR4000 ranges.


Celotex Insulation Board Key Features:

  • Features a good reaction to fire when measured in accordance with new European standards
  • Comes in conveniently sized boards for installation between cavity wall ties
  • A very cost-effective insulation
  • Very strong product that will not break easily
  • Easy to install and handle
  • Keeps performing long after it is installed for many many years
  • Lightweight product and easy to unload off a truck
  • Easy to cut making it easy then to install
  • Lightweight for ease of manoeuvring around site
  • Celotex Insulation has foil facings on both sides

Recent Name Change:


Recently Celotex boards went under strict review due to the Grenfell Tower incident. As a result, most of the general application boards (Celotex GA4000 and Celotex TB4000 range) were downgraded in their thermal performance from 0.022 to 0.023. As a result of this Celotex changed the names of the boards affected by this to TB3000 and Celotex GA3000 range.


This change as a result of the Grenfell Tower disaster has now been undone. Celotex and local government testing has done extensive testing on all the Celotex range and as a result, the new Celotex TB4000 and Celotex GA4000 range meets the required standards to meet the Thermal Conductivity of 0.022. As of now all Celotex range of products like celotex floor insulation are listed here meets and exceeds all requirements set upon it.




In conclusion, with all the above information it's easy to see why Celotex insulation board is such a popular choice of pir insulation for both domestic and commercial properties. By choosing celotex you can be rest assured that you will get great results.

For further details on Celotex Products please contact us here and we will be happy to assist you.

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