Foams

Expanding Foams for Sealing, Insulating & Fire-Stopping - PU, Acoustic & Fire-Rated Foams

Expanding foams are essential filler tools in construction and property maintenance, offering an efficient way to seal gaps, fix components, and improve thermal and acoustic performance. Formulated to expand on application, these foams fill voids and irregular spaces that would be difficult to address using traditional sealants or fillers. Once cured, they create a semi-rigid barrier that is resistant to air movement, moisture, and in some cases, fire and sound transmission.

Our foam range includes single-component polyurethane foams for general filling and sealing, low-pressure foams for precision work around doors and windows, and fire-stopping foams that comply with compartmentation requirements in walls, floors, and ceilings. Acoustic foams reduce airborne sound transfer, making them ideal for sealing voids in internal partitions or service risers. Whether you need a flexible, high-yield product or a foam with structural rigidity, we supply variants to meet the needs of trade professionals and experienced DIY users alike.

Foams are typically dispensed from aerosol cans, either by straw (handheld) or via a foam gun for controlled, continuous flow. Most products cure in just a few hours and can be trimmed once hardened. They adhere well to common substrates including wood, brick, concrete, and plastics. Some foams are moisture-cured and require surface dampening before use, while others are formulated to expand with minimal pressure - ideal for delicate frames or lightweight assemblies.

From installing door frames and window units to sealing pipe penetrations or insulating loft spaces, foams deliver quick, professional results with minimal mess. We also stock foam applicators, cleaners, and accessories to support precision work and ongoing maintenance. With high coverage rates, ease of application, and multi-purpose performance, expanding foams are a practical solution for air sealing, insulation, and joint filling across countless building scenarios.

Foams FAQs

What’s the difference between handheld and gun-grade foam?

Handheld foam comes with an attached straw for simple, one-off applications. Gun-grade foam requires a dedicated applicator gun, allowing for better control, more precise flow, and cleaner starts and stops - especially useful for repeat or large-scale work. Gun-grade foams are typically preferred by professionals for their accuracy and reduced waste.

Can expanding foam be used outdoors?

Yes, many foams are suitable for external use once cured. Outdoor-rated foams are resistant to moisture and temperature fluctuations, though they may require protection from UV exposure using sealant, paint, or cladding. Always check the product label to ensure it's intended for exterior use.

How long does expanding foam take to cure?

Most expanding foams become tack-free within 5–15 minutes and can be trimmed after 30–90 minutes, depending on conditions and product type. Full curing usually occurs within 12–24 hours. Moisture in the air or surface can accelerate curing - some foams perform best when substrates are lightly misted with water beforehand.

Can expanding foam be used for fire-stopping?

Only fire-rated expanding foams are suitable for fire-stopping. These are tested to resist flames and prevent fire spread through service penetrations, cavities, or joints. Always use a product with verified fire resistance performance and follow the installation guidelines for certified fire protection.

Is expanding foam safe to use around electrical cables or pipes?

Yes, most foams can be used safely around cables and pipes once cured, but they must not be applied directly onto hot surfaces or used to insulate live electrical equipment. For large pipework or sensitive areas, select a foam that specifies compatibility with electrical or plumbing applications.