Mega Expanding Foam 750ml

Bond It B3 Fill & Fix PU Foam is a one-component, fast-curing polyurethane foam engineered for high-performance filling, bonding, sealing, and insulating in construction applications. This versatile product is supplied in both handheld and gun-grade variants and is ideal for professional installers who demand consistency, efficiency, and high yield from an expanding foam.

Product Overview and Features

This foam is based on a moisture-curing polyurethane prepolymer that expands on application and cures to form a semi-rigid, predominantly closed-cell structure. Once cured, it exhibits minimal shrinkage, ensuring a long-lasting, secure fit that resists deformation or separation from the substrate. Its impressive expansion (up to 28 litres per can) makes it particularly suitable for filling large gaps and cavities.

It adheres well to most conventional building materials, including wood, concrete, plaster, metal, PVC, and polystyrene. However, it does not adhere to polyethylene, Teflon, silicone, or oily/greasy surfaces.

Performance and Benefits

• Fast Tack-Free and Cutting Time: With a tack-free time of 6–12 minutes and a cutting time of under 45 minutes, installation can progress quickly.

• Thermal and Acoustic Insulation: The cured foam offers excellent thermal conductivity of 0.033 W/(m·K) and a sound reduction index of 62 dB, making it effective for energy efficiency and noise control.

• Durable and Weather-Resistant: Once cured, the foam remains effective in a temperature range of -50°C to +90°C. It is resistant to ageing, although it must be protected from UV exposure.

• Mechanical Strength: Offers compressive strength greater than 10–35kPa, tensile strength (dry surfaces) of >65kPa with 13% elongation, and >30kPa with 8% elongation on moist surfaces.

• Low Vapour Permeability: Water vapour permeability is rated below 0.04–0.06 mg/(m·h·Pa), ensuring reliable sealing performance.

Applications

This product is suitable for a wide range of building and renovation tasks, including:

• Installation of window and door frames

• Insulating and sealing pipe penetrations

• Filling holes and gaps in construction elements

• Sealing of thermal and acoustic insulation boards

• Joint connections and reducing thermal bridging

Application and Installation Notes

For optimal results, the substrate must be firm, clean, and well-moistened before application. Moisture is critical for proper curing and post-expansion control. The foam expands 1.5 to 2 times its original volume, so joints should not be overfilled.

Application temperatures should range from +5°C to +30°C, with an ideal working temperature of +20°C for both can and ambient environment. Cans must be shaken thoroughly (15–20 times) before use and kept within the correct temperature range to avoid performance issues or safety risks. If the foam is being applied in colder temperatures, the can should be warmed gently in lukewarm water, ensuring it does not exceed 50°C.

For the gun-grade variant, care must be taken during attachment to avoid accidental discharge. Foam output can be adjusted via the gun trigger for precise application.

Storage, Shelf Life, and Cleaning

The foam must be stored upright in cool, dry conditions (5°C to +30°C) and kept away from direct sunlight or heat sources. Shelf life is 12 months in unopened containers from the date of manufacture.

While wet, excess foam can be cleaned using Bond It FOAM CLEANER or MULTI-WIPES. Once cured, foam must be removed mechanically.

Environmental and Sustainability Notes

The foam contains a propellant that complies with current EU regulations banning CFCs. Additionally, SPS Envirowall promotes responsible disposal and recycling of its packaging materials through site-based environmental recycling schemes.

Limitations

• Cured foam must be protected from UV rays using a suitable opaque finish.

• Not suitable for adhesion to non-stick surfaces like polyethylene, Teflon, and silicone.

• Lightweight elements should be firmly fixed before foam application due to the product’s high post-expansion.

Technical Data