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Here you will find the latest articles written by our team focusing on insulation solutions, product developments, and technical guidance.

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Insulating a garage: how to insulate a garage conversion

Published Date Published : 08 October 2025
Authored By Authored By : David Milner

Garage conversions are a popular way to expand the living space in a home, transforming a previously under-utilised area into valuable living space, such as a lounge, a kitchen extension or even a bedroom.
Categories: Installation ,  Technical
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Insulation’s role in the Future Homes and Building Standard (FHBS)

Published Date Published : 11 August 2025
Authored By Authored By : Mike Vaczi

The Future Homes Standard was first proposed by government in 2019. Despite plans for implementation in 2025, as of the time of writing, the final details of the Future Homes and Buildings Standard (FHBS) have yet to be confirmed.
Categories: Part L ,  Technical
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What is cavity wall insulation?

Published Date Published : 23 July 2025
Authored By Authored By : David Milner

Masonry cavity wall construction dates to the early 1900s. Since then it has become the predominant method for constructing the external walls of low-rise buildings, and housing in particular.
Categories: Technical
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What’s the role of thermal insulation in preventing condensation in buildings?

Published Date Published : 18 July 2025
Authored By Authored By : David Milner

Effective condensation control in buildings can be summed up as a three-pronged strategy: insulate correctly, provide adequate ventilation and manage the movement of moisture.
Categories: Technical
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What is the standard assessment procedure (SAP) and how does it work?

Published Date Published : 15 July 2025
Authored By Authored By : Mike Vaczi

The Standard Assessment Procedure (SAP) is a method for assessing the energy performance of residential buildings. It applies to new builds or existing buildings undergoing refurbishment or material change of use, including extensions and conversions.
Categories: Technical
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Comparing insulation: which one is right for your project?

Published Date Published : 11 July 2025
Authored By Authored By : Mike Vaczi

Effective thermal insulation is an important part of building design. It plays a crucial role in reducing energy consumption, improving occupant comfort, supporting sustainability goals and meeting regulatory requirements.
Categories: Technical
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Understanding the performance gap: how BREL and BRWL reports support compliance

Published Date Published : 09 July 2025
Authored By Authored By : Mike Vaczi

The Building Regulations require all new homes in England and Wales to meet specific energy efficiency standards, both at the design stage and after construction.
Categories: Technical
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Guide to polyisocyanurate (PIR) insulation

Published Date Published : 04 July 2025
Authored By Authored By : David Milner

Polyisocyanurate, or PIR, is a type of thermal insulation which was developed as an advancement from polyurethane (PUR) insulation.
Categories: Technical
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Comprehensive guide to floor insulation

Published Date Published : 27 June 2025
Authored By Authored By : David Milner

Floor insulation is often overlooked with more focus typically placed on insulating walls and roofs. After all, if heat rises, how much impact can the floor really have on keeping us warm?
Categories: Technical
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The role of thermal bridging in energy efficient buildings

Published Date Published : 20 June 2025
Authored By Authored By : David Milner

Thermal bridging heat losses have been part of energy efficiency regulations and compliance calculations in Approved Document L since 2006. With every regulatory update since, in all parts of the UK, thermal bridging’s role has become increasingly important.
Categories: Technical
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Standards relating to insulation: what is BS EN 13165, BS EN ISO 13788 and BS 5250:2021?

Published Date Published : 27 May 2025
Authored By Authored By : David Milner

British and European standards relating to thermal insulation can be grouped into two approximate categories: those to do with the manufacture and testing of the insulation products themselves; and those relating to how products are used as part of wider building construction.
Categories: Technical
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How Celotex’s Technical Team adds value through expert insulation support

Published Date Published : 25 April 2025
Authored By Authored By : Mike Vaczi

Creating buildings designed for reliable thermal efficiency isn’t simply about material selection. It demands precise understanding of how insulation integrates with the entire building fabric.
Categories: Technical
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XPS vs. PIR insulation: Understanding the differences for your project

Published Date Published : 28 March 2025
Authored By Authored By : Mike Vaczi

When comparing XPS vs. PIR insulation for a building project it is important to understand how the properties of XPS insulation differ from those of PIR insulation.
Categories: Technical
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Understanding condensation risk analysis

Published Date Published : 05 March 2025
Authored By Authored By : Mike Vaczi

Effective moisture management is essential to prevent condensation risks, ensuring the health and comfort of a building’s occupants. Condensation risk analysis is therefore a key tool when designing and specifying building fabric elements, including floors, walls, and roofs.
Categories: Technical
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What are the full fill and partial fill insulation options for masonry cavity walls?

Published Date Published : 21 October 2021
Authored By Authored By : Mike Vaczi

Polyisocyanurate (PIR), glass mineral wool and blown insulation products may be specified as full and partial fill insulation solutions to improve the U-value of a masonry cavity wall.
Categories: Technical
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What full fill insulation options are available for masonry cavity walls?

Published Date Published : 02 September 2021
Authored By Authored By : Mike Vaczi

Masonry cavity wall constructions can be filled with a rigid full fill polyisocyanurate (PIR) insulation product, the selected product should carry third-party certification confirming its suitability for use in cavity wall applications.
Categories: Technical
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How does rigid full fill cavity wall insulation work?

Published Date Published : 26 August 2021
Authored By Authored By : Mike Vaczi

Traditionally, rigid insulation boards used in masonry cavity wall applications were offered only as a partial fill solution. Now, rigid full fill solutions for masonry cavity walls mean the clear air cavity can be significantly reduced or eliminated entirely.
Categories: Technical
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What is perimeter upstand insulation in solid floor constructions?

Published Date Published : 16 November 2020
Authored By Authored By : Mike Vaczi

The use of perimeter upstand insulation is key to stopping heat escaping through the edge of the screed or concrete oversite in solid floor constructions.
Categories: Technical
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What is a vapour control layer (VCL)?

Published Date Published : 10 November 2020
Authored By Authored By : Mike Vaczi

This post aims to cover what a vapour control layer is, why it’s important and when it’s applicable to roof and floor applications. Today, we are talking about another vital construction component called a vapour control layer, or a VCL.
Categories: Technical
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What is PAS 2030 and how does it apply to the Green Homes Grant?

Published Date Published : 19 October 2020
Authored By Authored By : Mike Vaczi

Publicly Available Specification (PAS) 2030:2017 describes how energy efficiency measures in dwellings should be specified, installed and commissioned. It forms part of a network of standards and quality assurance measures intended to deliver high quality retrofit work.
Categories: Technical
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A homeowner’s guide to the Green Homes Grant scheme

Published Date Published : 02 October 2020
Authored By Authored By : Mike Vaczi

The government has launched its new £2bn Green Homes Grant scheme. Through the scheme, eligible homeowners will be able to apply to help pay for the installation of energy efficiency measures such as thermal insulation, as well as new boilers, double glazing, draught-proofing and solutions such as air-source and ground-source heat pumps.
Categories: Technical
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