Online U-value Calculator

The Celotex U-value Calculator gives you instant access to calculating your required insulation thickness and product solution.

U-value Calculator
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This professional U-value calculator provides a much-improved service, allowing you to specify your desired U-value before immediately calculating the required insulation thickness and product solution.

"I use the members area of the Celotex website on a daily basis. In particular I use the U-value calculator within the member area because I can quickly produce U-value calculations for inclusion within my projects' specifications" - Robin Bradbury of Bradbury Design

In order to access the Celotex U-value calculator and download your calculation pdfs, you must register for the members area, which is quick and easy!

How to access and use the Celotex U-value calculator

The following video explains how to access and step through using the online U-value calculator. 


Register now to use the Calculator Calculator Icon

Why register?

Our U-value calculator app is also available from the App Store.

If you require further help or advice on an already created U-value calculation and would like to speak with an advisor, please contact our Celotex Technical Centre on 01473 820850.

Lines are open Monday – Friday, from 8.00am – 5.15pm.

Please note, some products in the U-value calculator may not be available from stock and subject to minimum order quantities and extended lead times.