Cavity wall insulation

Cavity Wall Insulation: Save Energy and Boost Comfort.

What is cavity wall insulation?

Cavity wall insulation involves filling the gap between a home’s inner and outer walls with insulating material. This gap, or cavity, was originally designed to prevent moisture buildup by allowing air to circulate. By insulating this space, you enhance your home’s thermal efficiency, keeping it warmer in winter and cooler in summer. This straightforward and cost-effective solution reduces energy use and improves indoor comfort. Learn more about the process of cavity wall insulation.

Benefits of insulating cavity walls

Cavity wall insulation is suitable for most homes with cavity walls and offers numerous advantages:
Improved indoor climate: Maintains warmth in winter and coolness in summer for consistent comfort.
Lower energy bills: Reduces the need for heating and cooling, saving you money.
Enhanced living comfort: Creates a more pleasant and healthier home environment.
Increased property value: A better energy rating boosts your home’s market value.
Reduced environmental impact: Lower energy consumption means fewer CO2 emissions.
Quick return on investment: savings often recoup costs within a few years.

Costs of cavity wall insulation

Before starting, a Thuiseco specialist will visit for a free consultation and provide a detailed cost estimate. The price depends on factors like cavity width, home size, accessibility, and the chosen insulation material. Typically, the investment pays for itself quickly through energy savings.

Available subsidies for insulation

In the Netherlands, various subsidies can help offset the cost of cavity wall insulation. These include:
ISDE Subsidy: The Investment Subsidy for Sustainable Energy and Energy Conservation (ISDE) is a key national program supporting energy-efficient upgrades, including cavity wall insulation.
Local Incentives: Many municipalities and provinces offer additional subsidies for home insulation. Availability and amounts vary, so check with Thuiseco for guidance on local options.

Insulation materials for cavity walls

Thuiseco offers five high-performance materials, each chosen for specific cavity widths and construction needs, ensuring optimal results across the Netherlands, Germany, Belgium, and the UK:

HR-Isowool (Knauf Supafil Cavity 033): A blown-in mineral wool with a Lambda of 0.033 W/mK, ideal for cavities 40–100 mm wide. It’s durable, moisture-resistant, and won’t settle over time, ensuring long-term performance. Perfect for both new and existing homes, it also provides excellent acoustic insulation.
Rockwool Fulfill: Advanced stone wool with a Lambda of 0.034 W/mK, designed for blown-in applications. Its lower blowing density makes it ideal for noise reduction—great for homes near busy roads or airports in urban areas like Amsterdam, Berlin, or London. It’s fire-resistant (Class A1) and suitable for cavities 50–150 mm wide.
HR-Isoplus 35 (Plixxent Plixxopol RF 640070): A two-component closed-cell polyurethane foam (PUR) with an R-value of ~6.2 per inch, injected into cavities 30–100 mm wide. It forms a seamless, airtight barrier, excelling in thermal insulation and moisture resistance. Ideal for new builds and renovations in damp climates like Belgium or the UK.
Isover Insulsafe Plus: Blown-in glass wool with a Lambda of 0.034 W/mK, perfect for cavities 40–100 mm wide in new or existing homes. It’s non-combustible (Class A1), water-repellent, and enhances both thermal and acoustic comfort, making it a versatile choice across all regions.
HR IsoPearl (Neopixels HR++ EPS Pearls): Graphite-enhanced EPS pearls with a Lambda of 0.033 W/mK, blown into cavities 30–100 mm wide. Their oval shape ensures a better fit, improving heat reflection and insulation efficiency. A top pick for cost-effective insulation in the Netherlands and Germany.

How cavity wall insulation is installed

Cavity wall insulation is applied by injecting or blowing insulation material into the cavity between the inner and outer walls. The process includes:
Inspection: A technician assesses the cavity’s suitability and measures its width.
Drilling: Small holes are drilled in a specific pattern at joint intersections.
Insulation Application: Material is blown or injected into the cavity until fully filled.
Finishing: Holes are sealed, restoring the wall’s appearance.
Ventilation Check: Crawl space ventilation is evaluated, and ventilation grilles are installed if needed to maintain airflow.
The process is efficient, typically taking a few hours to a day for an average home, depending on size and complexity.

Is your home suitable for cavity wall insulation?

Homes built after 1920 often have cavity walls, making them prime candidates for insulation. A specialist can determine if your cavity is suitable by assessing its width and condition. If your home lacks a cavity, alternatives like internal false walls or external insulation may be options. For homes built after 1995, which often have some insulation, other upgrades like facade maintenance (e.g., waterproofing) can extend wall lifespan and reduce maintenance costs while preserving property value.

Energy savings with cavity wall insulation

Cavity wall insulation is a sustainable way to save energy and enhance comfort. Its longevity depends on high-quality materials and proper installation. When done correctly, the insulation maintains performance for decades, delivering lasting savings.

Why Choose Thuiseco Insulation?

Trust Thuiseco Insulation for professional cavity wall insulation. Our experienced team specializes in home, floor, and roof insulation, using only top-quality materials. We offer a free consultation to assess your needs and provide expert guidance. Contact our customer service for answers to your questions.

Disclaimer

Last updated: May 28, 2025
At Thuiseco, we strive to ensure all information on this page is accurate and up to date. However, if you encounter any inaccuracies or outdated content, please don’t hesitate to contact us so we can address it promptly. While we aim for precision, no rights can be derived from the content of this page, and Thuiseco cannot be held liable for any errors or omissions.

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