Cavity Wall Insulation | Cavity Wall Insulation Board

Cavity wall insulation is an essential component in modern construction, offering energy efficiency and comfort to buildings. At Build4Less, we provide a comprehensive range of insulation solutions tailored to meet various requirements and budgets.

Types of Cavity Wall Insulation Products

Polyisocyanurate (PIR) Boards

Products like the Celotex CW4000 and Kingspan Kooltherm series are premium PIR boards known for their excellent thermal performance and compressive strength. These boards are easy to handle and install, making them ideal for new construction and refurbishment projects.

Mineral Wool Insulation

Rockwool products, such as RW3, RW5, and Rockwool Cavity, offer superb acoustic insulation, fire resistance, and thermal properties. These are particularly suited for projects where fire safety and sound reduction are priorities.

Glass and Stone Wool Slabs

Knauf Dritherm Cavity Slabs are non-combustible, water-repellent glass mineral wool slabs that provide thermal and acoustic insulation in cavity walls. They are designed to maintain their structural integrity over time, ensuring long-lasting performance.

Expanded Polystyrene (EPS) Boards

High-density EPS 200E boards are versatile and cost-effective insulation solutions. They are suitable for various applications, including cavity wall insulation, due to their excellent resistance to moisture and high insulation values.

Cavity Closers

Kingspan Kooltherm Cavity Closers prevent thermal bridging and provide a clean finish around openings in cavity walls. These are essential for energy-efficient construction, ensuring that the insulation continuity is maintained around windows and doors.

Speciality Insulation Products

Products like Sheepwool Loose Wool and Window and Door Filler provide sustainable and natural alternatives for cavity wall insulation, offering breathability and moisture control.

Hybrid Insulation Materials

Hybrid materials such as HControl Hybrid combine insulation with a reflective surface to provide a unique solution for thermal regulation, while Thin-R Cavity offers a slim-profile PIR solution for tight spaces.

Selecting the Right Cavity Wall Insulation

When choosing cavity wall insulation:

• Consider the U-value requirements for your project; lower U-values mean better insulation.
• Evaluate the fire rating needed, especially for high-risk areas or multi-story buildings.
• Think about acoustic needs; if sound insulation is a priority, mineral wool may be the best choice.
• Assess the space available; if the cavity is narrow, slim-profile boards like Thin-R Cavity could be ideal.
• For eco-friendly projects, consider natural options like Sheepwool products.

Benefits of Cavity Wall Insulation

• Energy Savings – Lower heating and cooling costs by reducing heat loss through walls.
• Improved Comfort – Creates a consistent indoor temperature all year round.
• Noise Reduction –  Mineral wool slabs and stone wool products also absorb sound for quieter living.
• Sustainability –  Many options are recyclable or made from natural fibres.
• Fire Safety –  Full-fill mineral wool insulation is A1 non-combustible, offering additional protection.
• Space Efficiency –  Phenolic and PIR boards achieve high thermal performance in slimmer wall cavities.

Applications of Cavity Wall Insulation

• New-build homes and extensions –  Cavity Wall Insulation is used to meet U-value targets and comply with Approved Document L.
• Commercial buildings – Cavity Wall Insulation is used in Offices, schools, and healthcare facilities where energy performance is key.
• High-exposure areas – Cavity Wall Insulation is used in Mineral wool solutions are widely specified in coastal or exposed regions.
• Refurbishments – Cavity Wall Insulation is Ideal for upgrading existing cavity wall systems to meet modern efficiency standards.

Installation Tips for Solid Wall Insulation

• Always follow manufacturer guidelines and BBA certificates.
• For partial-fill boards, maintain the required residual cavity and tightly butt boards together.
• Stagger joints and tape foil faces where recommended to minimise thermal bridging.
• Keep insulation dry before and during installation to protect performance.
• Use the correct cavity ties and retainers with mineral wool slabs.
• Ensure all wall openings are properly detailed with cavity closers for airtightness and thermal continuity.

Why Choose Build4Less (B4L)?

• Wide Range of Trusted Brands – From Celotex and Kingspan to Knauf, ROCKWOOL, and natural insulation brands.
• Competitive Pricing – Trade-friendly rates with bulk discounts and seasonal promotions.
• Fast UK Delivery – Reliable nationwide delivery direct to site.
• Expert Support – Our team can help with product selection, U-value calculations, and technical queries.