Welcome to the Celotex Insulation Blog

Here you will find the latest articles written by our insulation specialists focusing on product developments, building regulations and technical guidance notes.

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Category Archives: Technical

IMPORTANT: On 1 September 2017, Celotex took the precautionary measure to temporarily suspend the supply of Celotex FR5000, Celotex CG5000, Celotex CF5000 and Celotex SL5000 while we investigate the results of recent tests (Parts 6 and 7 of British Standard 476). Materials relating to these products are for information only.

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Over the last few months we have continued our Technical Twitter Takeover’s, featuring monthly hour long sessions dedicated to different topics affected by insulation and what we do here at Celotex. Within the Celotex Technical Centre (CTC) our fantastic team of technical advisors get asked a range of different questions so it is great to take some of those questions and explain them through a short afternoon of Twitter activity. It is also a great opportunity for those watching from across the social media stratosphere with a project enquiry to send in a Tweet using #AskCelotex to our technical team member to provide assistance.

The Celotex Floor Technical Twitter Takeover

So, February’s TTT focused on the top of your house with a pitched roof application and the topic for March was at the other end, looking at floor applications. Here are some of the questions that Celotex are asked regularly about floor applications and insulation solutions.

Question 1 – What membranes should I use in a solid ground floor with Celotex insulation?
Celotex should be positioned above a dpm and below a minimum 500 gauge polythene seperating layer.

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The Celotex Pitched Roof Technical Twitter Takeover

The February Technical Twitter Takeover saw focus on pitched rCelotex Insulation Technical Twitter Takeoveroof application, including topics such as Building Regulations, ventilation and insulation between rafters.

Let’s crack on with the questions.

Question 1 – What U-values do I need to achieve to hit Building Regulations for an existing pitched roof? #AskCelotex. Under normal circumstances, existing pitched roofs would require a u-value of 0.18 W/m2K. Read more »

Celotex and Sustainability

Did you know?

  • Energy used in homes is responsible for over 25% of the UK’s CO2 emissions
  • UK households account for 61% (and rising) of total UK gas consumption
  • UK householder spending on energy has doubled since 2003. A household is deemed fuel poor if it spends more than 10% of its income keeping warm
  • 45% of heat is lost through uninsulated solid walls. Installing solid wall insulation nationwide could save up to 14m tonnes of CO2. That’s the equivalent emissions of 3.5 million cars!
  • 2.3 million solid wall installations are required by 2022 to meet current climate change targets
  • High performance thermal insulation continues to be one of the most cost effective measures for improving thermal efficiency and tackling climate change

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It’s a new year which means a new start, but what were your top 8 questions of 2014? This brief blog looks at what we covered in the final Technical Twitter Takeover of 2014 pointing you in the right direction for some of the key questions sent in to us at Celotex.

Need to know where to find out about the installation of Celotex?

After some guidance on insulating walls, floors and roofs with Celotex?

Or perhaps just after some of the key benefits of using Celotex in your projects?

This post is a good starting point. So, let’s get into it! Here is the summary of the 8 questions tackled.

1.    How do I Install Celotex?

That depends upon your specific application. Celotex is suitable for use in your floors, walls and roofs. The best place to start is with our Handy Guide which is available on our website here: http://www.celotex.co.uk/resources/the-handy-guide. Our Handy Guide is a useful tool for identifying our range of product and their use, but it also includes our application installation guidelines. All applications from floors, to walls, up to roofs are included with installation guidelines in our Handy Guide.

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Celotex Technical Team Member Rob Firman

My name is Rob Firman and I’m a new member of the Celotex Technical Centre team. I joined the company following technical roles at a roofing systems manufacturer and a storage tank manufacturer. I have had some experience of insulation in the past so realise insulation is much more than the ‘fluffy stuff’ that sits in your loft. However, in my initial weeks with the company I have undergone a thorough and intensive training programme to allow me to ‘know insulation inside and out’. Throughout this time I have learnt many things about Celotex Insulation and PIR insulation in general. With this in mind I have used my blogging debut to share my ‘top 5 things I didn’t know about insulation’.

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Acronyms here. Acronyms there. Acronyms pretty much everywhere. It seems like you never have to go far in the world before you stumble across a sequence of letters that seemingly make little sense without knowledge of the topic. Very often though, they are important and need to be understood fully in order to grasp and talk confidently about industry specifics. So, if you are in the construction industry, and someone is asking what’s your SAP? How good is your U-value? Or have you done a SBEM calculation? You will have a heads up on what some of those mean and their importance.

This month’s Celotex Technical Twitter Takeover looked to point you in the right direction giving you an insight in to some of the various different acronyms and key terms that are present in the construction industry. From R-values to BREEAM, this brief blog runs through some of those terms that you might not have discovered yet.

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What are Celotex Energy Assessments?

Celotex Energy Assessments (CEA)
 provide a comprehensive range of energy efficiency and sustainability services.It can be difficult working to ever-changing Regulations but keeping up to date or even planning ahead is something we at Celotex can help with. Our energy assessment service demonstrates that we would rather build a long-term relationship with you than do a one-off job.

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Update – IMPORTANT: On 23 June 2017, in view of the focus on components of rainscreen cladding systems, Celotex stopped the supply of Celotex RS5000, pending further clarity.  RS5000 remains suspended. Celotex do not currently supply a solution for buildings over 18 metres.

In December 2017 we identified a compliance issue relating to our calculation and testing of the lambda value of products in our 4000 and 5000 range and the Crown-Bond and Crown-Fix products within Crown Flat Roofing range. Material such as product downloads & specifications is for information only.

On 30 January 2018, Celotex made a further public announcement in relation to the full system testing of RS5000 pursuant to BS8414:2.  The announcement can be read here


On September 19th 1928, construction started in New York on the Chrysler Building. Standing 319m high to the top of the spire the Chrysler building held the record for the world’s tallest building for less than a single year, when it was surpassed by the newly completed Empire State Building.


Designed in a distinctive Art Deco style, the façade of the Chrysler Building is constructed entirely of bricks over a load bearing internal steel frame.

Approximately 3,826,000 bricks were used in the construction of the outer walls – each laid by hand. The building was constructed over the course of 18 months and completed on 20th May 1930.

The Chrysler building stands today as an American cultural icon and still remains the world’s tallest brick structure. Whilst this building stands as a unique example of the versatility of bricks, the imperatives of modern building design make them a challenging choice for today’s high rise buildings.

Rainscreen Cladding

Ventilated facade systems offer a number of benefits to the building designer.

Lightweight, durable and available in a huge range of materials, rainscreen systems allow buildings to achieve their aesthetic goals whilst utilising practical construction methods.

A typical rainscreen construction consists of non-structural cladding panels supported by aluminium brackets and rails. A drained and ventilated cavity is maintained behind the cladding and the system is fixed back to a lightweight metal frame or masonry substrate. Insulation material can be provided behind the cladding and optionally between the metal frame where present.

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