Can you use Celotex as a cavity closer?
No, you shouldn’t use Celotex as a cavity closer. Celotex is designed for insulation, not to seal the cavity around windows and doors in masonry walls. Cavity closers serve to prevent heat loss, improve fire safety and minimise moisture ingress. For correct installation techniques and compliance with regulations, choose purpose-built materials like uPVC and EPS.
Understanding Celotex
Celotex insulation boards are renowned for their effectiveness in providing thermal insulation within walls, floors and roofs. Composed primarily of polyisocyanurate foam, these boards excel in reducing heat transfer and enhancing energy efficiency within building elements. However, their composition and intended use as thermal insulation are distinct from the requirements of a cavity closer.
Why Can You Not Use Celotex As a Cavity Closer?
Structural Support and Durability
Cavity closers need to withstand environmental stresses and provide structural support around openings. Unlike purpose-built materials such as uPVC (unplasticised polyvinyl chloride) or EPS (expanded polystyrene), Celotex lacks the necessary rigidity and durability to effectively seal cavity walls. Over time, this could lead to compromised structural integrity and potential issues with moisture ingress.
Regulatory Compliance
UK building regulations, specifically Part L of the Building Regulations, stipulate specific requirements for cavity closers to ensure proper thermal performance and structural stability. Substituting Celotex for designated cavity closers may result in non-compliance with these regulations, posing risks during building inspections and potentially affecting insurance and warranty claims.
Thermal Efficiency Concerns
Cavity closers need to fit tightly and securely around window and door openings to prevent air leakage and thermal bridging. While Celotex boards can insulate effectively within solid building elements, they may not have the necessary flexibility or sealing properties to achieve a proper fit and seal around openings in masonry walls. This could lead to gaps or insufficient coverage, compromising the overall thermal performance of the building envelope.
Choosing the Right Product and Materials
Using Celotex inappropriately could compromise the building’s structural integrity, thermal efficiency and compliance with building regulations. It’s therefore essential to adhere to best practices in construction and utilise purpose-built materials like uPVC and EPS for cavity closing applications to ensure optimal performance and long-term durability of the building envelope.
By choosing the right materials and following correct installation techniques, builders and homeowners alike can contribute to creating energy-efficient and compliant buildings that stand the test of time.
Market-Leading Cavity Closers at Subframes UK
Subframes UK is the largest trade supplier of welded and mechanically joined cavity closers in the UK, offering a wide range designed to meet the diverse needs of modern construction projects. With a commitment to quality and compliance with building regulations, Subframes UK only partners with the most reputable brands in the industry.
Operating from our Midlands-based factory, our team manufactures high-quality cavity closers for both commercial and domestic properties. We prioritise precision and excellence in every product, guaranteeing exceptional thermal efficiency and structural integrity that meets and exceeds regulatory standards.
Whether you’re tackling a small renovation or overseeing a large-scale commercial build, the experienced team at Subframes UK is here to support you. For quotations, product information or technical support, please contact us today.
