18th Mar 2024 -

With growing concerns about the impact of buildings on the environment, there is an increased focus on reducing energy consumption and carbon emissions from homes and other building types. 

An effective way to reach sustainability goals is through the use of Celotex insulation boards. For this feature, we explore best practices for installing Celotex insulation to build sustainable construction projects.

How much does insulation impact sustainability? 

Insulation is a crucial element in designing an energy-efficient, eco-friendly building. The insulation you choose to lay or install plays a role in reducing energy consumption and lowering carbon emissions. 

By providing an effective thermal barrier, quality insulation helps minimise heat loss in winter and heat gain in summer. High-performance insulation also enables passive house principles, using the building’s envelope to maintain comfortable temperatures.

Learn more about how thermal insulation works with our comprehensive guide.

5 Celotex insulation sustainability benefits

Celotex insulation delivers multiple eco-friendly factors. From recycled content to renewable production methods, here are the 5 ways Celotex insulation provides environmental benefits.

1. Unmatched thermal performance

Some Celotex insulation board options offer an excellent R-value rating of up to R-9 per inch. An R-value measures the thermal resistance of insulation, indicating how effectively it resists the flow of heat. To compare, an average insulation board achieves an R-value of R4. 

Its polyisocyanurate (PIR) insulation delivers exceptional efficiency with minimised thickness, reducing environmental footprint.

2. Low global warming impact

Celotex has low global warming potential compared to other types. It uses blowing agents with low volatile organic compound (VOC) content and global warming potential. This limits its lifetime environmental impact.

3. Eco-friendly recycled content

Each Celotex board incorporates up to 50% of recycled content. As a result, it diverts waste from landfills and reduces demand for newer materials. Celotex boards are also recyclable.

4. Optimised building efficiency

The boards optimise the building envelope performance when properly installed. Continuous insulation from Celotex dramatically improves energy efficiency, lowering consumption and emissions.

5. Green building certifications

Celotex contributes to green building credits and certifications. Sustainability benefits like recycled content and energy optimisation help projects achieve industry recognition. This includes a Building Research Establishment Environmental Assessment Methodology (BREEAM) certification. 

What thickness of Celotex board to use

Board thickness has a major impact on the sustainability of the building envelope. Follow these guidelines for strategic insulation thickness selection.

  • Use thinner sheet options like 25mm Celotex GA4000 to reduce material usage in space-limited cavities. However, ensure R-values meet minimum requirements.
  • For standard 140mm stud walls, 100mm Celotex insulation is suitable in warmer climates, while 120mm or 150mm are recommended for colder regions to hit thermal targets.
  • In a 50mm cavity between rafters, 50mm Celotex can achieve up to R-7 with its high thermal resistance per inch. This avoids hindering performance for slimmer assemblies.
  • Limiting thickness variations to reduce board joints also improves moisture resistance and airtightness. Use consistent 150mm Celotex XR4000 for entire roof assemblies whenever feasible.
  • For high R-value ceilings, combine a thick 150mm Celotex insulation layer with 50mm insulation above the rafters to achieve higher R-values.

How to install Celotex into sustainable projects

Maximising the benefits of Celotex insulation should be a top priority for builders. Follow these top tips to boost the sustainability benefits Celotex brings to your green building structure.

  • Choose the optimal product: Consider required R-values, vapour barrier needs, thickness constraints and building standards. Select the Celotex product that delivers maximum thermal performance in the slimmest profile.
  • Master proper installation: Adhere to industry best practices for installing Celotex boards. For masonry walls, use adhesive dabs to avoid thermal bridging through fasteners. With framed walls, carefully seal joints with tape. Cut boards for a tight fit around openings.
  • Insulate the full envelope: Use Celotex insulation consistently across external walls, roofs, floors and foundations. This boosts the performance of the entire building envelope by eliminating thermal weak points. 
  • Target BREEAM criteria: Celotex insulation contributes to several BREEAM categories including energy and materials. Focus on criteria for building envelope, lifecycle impacts, insulation and thermal comfort.
  • Introduce advanced solutions: Use cutting-edge products like aerogel insulation boards for maximum thermal performance in space-constrained envelope areas. Aerogel insulation provides extremely high R-values in very slimline boards.

Can you adjust Celotex insulation by application?

While Celotex insulation enhances sustainability across the board, maximising eco-friendly benefits requires tailoring installation plans to each application type. Fine-tuning solutions for walls, roofs, floors and hybrid assemblies unlocks the full sustainable potential.

ApplicationSpecific installation tips
Exterior wallsUse Celotex external wall insulation such as GA4000 or XR boards with plasterboard laminate facers for improved moisture resistance.
Seal joints and penetrations with Celotex tapes to maintain air barrier continuity.
Adhere cavity boards with insulation adhesive to avoid thermal bridging from impaled fasteners.
Roof/loft spacesCombine layers between and over rafters. Use 150mm Celotex roof insulation boards for higher insulating performance.
Offset staggered joints and tape to prevent air leakage paths.
Incorporate vapour control layer (VCL) membranes or foil boards for vapour control.
For flat roofs, use Celotex FR5000 boards in two staggered layers with offset joints.
FlooringUse 70mm-150mm load-bearing floor insulation depending on joist spacing.
Trim boards tightly and apply edge strips to maintain the air barrier.
Hybrid assembliesSpecify Celotex PL4000 for external basement wall insulation with internal drylined ceiling for maximum envelope coverage.

Final checklist: Sustainability with Celotex insulation

To strive for peak energy efficiency and sustainability, proper installation is critical. Follow this checklist to ensure Celotex insulation delivers maximum green building performance.

  • Choose the appropriate Celotex insulation product based on project specifications such as thermal and sustainability criteria.
  • Ensure the selected product meets relevant Building Regulations for energy efficiency. 
  • Whether it is roof, floor or Celotex wall insulation, adhere to the above installation techniques to boost effectiveness. 
  • Seal any gaps or air leaks effectively to enhance building envelope efficiency and prevent energy loss.
  • Minimise waste disposal by introducing efficient handling practices.
  • Carry out quality checks to verify that insulation is installed without compression or gaps. Promptly fix any issues to avoid low performance.
  • Evaluate the performance of Celotex insulation post-installation to ensure it meets sustainability goals.

What is the future for Celotex and sustainability?

Celotex and Isover (another Saint-Gobain brand) have partnered with British Gypsum to form Saint-Gobain Interior Solutions. With precise plans developed through 2025, all 3 brands aim to make significant progress towards net zero carbon emissions by 2050.

Saint-Gobain has created a roadmap to sustainability, with 5 workstreams targeting manufacturing, operations, products and services. From revamping production processes to optimising customer recycling, their 2030 goals aim high.

  • Slashing water withdrawal by 50% in high-risk areas.
  • Cutting CO2 emissions across all operations - from raw materials to transport.
  • Diverting 80% of non-recovered production waste.
  • Increasing recycled and bio-sourced packaging content to 30%.
  • Completing Life Cycle Assessments for all product ranges.

Buy sustainable Celotex insulation materials

We proudly offer a high-quality range of Celotex insulation products for energy-efficient and sustainable construction. Our extensive selection ensures easy access to Celotex's cutting-edge insulation materials.

Whether you are working on a residential project or a commercial development, our commitment to quality helps you deliver exceptional results. You can rely on us for all your material needs, from Celotex floor insulation to Celotex plasterboard.

For trade customers seeking a streamlined and efficient experience, consider opening a trade account with us. With a trade account, you will benefit from knowledgeable advice, fast UK delivery and one-on-one account management.

We understand the importance of a smooth procurement process. By opening a trade account with us, you establish a partnership that prioritises your success. Join the many satisfied builders who trust us as their go-to supplier. Sign up now or contact the team to learn more.







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