Expanding Foam Guns

About Expanding Foam Guns

Expanding foam guns, also known as PU foam guns or foam applicator guns, are professional-grade tools designed to dispense expanding polyurethane foam with precision and control. Unlike disposable aerosol cans with fixed straws, these reusable tools feature adjustable flow control, trigger mechanisms for start-stop accuracy, and threaded baskets that accept larger gun-grade foam cartridges. MyToolShed.co.uk stocks expanding foam guns from leading manufacturers including Everbuild, Draper, Roughneck, Fischer, and Sealey, ranging from medium-duty models for occasional use to heavy-duty professional guns with Teflon-coated barrels for enhanced durability and easier cleaning.

Whether you're sealing around window frames, insulating cavities, filling structural gaps, or securing fixtures, a quality foam gun transforms polyurethane foam application by reducing waste, improving accuracy, and allowing partially used cartridges to remain attached between jobs for weeks at a time. Professional models feature quick-release cartridge mechanisms, precise flow adjustment from narrow beads to full discharge, and compatibility with standard foam gun cleaners for straightforward maintenance.

Applications

Expanding foam guns are essential tools for a wide range of construction professionals and tradespeople:

• Builders and General Contractors: Cavity filling, structural gap sealing, and insulation work on residential and commercial projects
• Window and Door Fitters: Sealing around frames, eliminating draughts, and ensuring weather-tight installations
• Insulation Specialists: Professional cavity wall insulation, loft work, and thermal bridging solutions
• Plumbers and Heating Engineers: Sealing pipe penetrations, insulating pipework, and filling voids around installations
• Electricians: Sealing cable entry points, fire-stopping requirements, and maintaining building integrity
• Roofers: Sealing roof penetrations and gaps around roof windows
• Property Maintenance Professionals: Repairs, draught-proofing, and general gap-filling tasks
• DIY Enthusiasts: Home improvement projects including loft insulation and renovation work

Choosing The Right Expanding Foam Guns

Build Quality: Professional metal-bodied guns offer superior durability for daily site work, whilst lighter-duty models suit occasional users. Teflon-coated barrels significantly ease cleaning and prevent foam build-up, making them worthwhile for regular applications.

Duty Rating: Match the duty rating to your workload—medium-duty guns suit lighter applications and occasional use, whilst heavy-duty models like the Everbuild P65 are engineered for continuous professional use with multiple cartridges daily.

Adjustability: Look for guns with precise flow control mechanisms allowing fine adjustment from narrow beads to full discharge. This versatility is essential when working across different applications, from delicate seal work to large cavity filling.

Cleaning Features: Models with easy-clean designs, quick-release cartridge mechanisms, and compatibility with standard foam gun cleaners save considerable time. MyToolShed.co.uk recommends investing in professional models with accessible mechanisms for straightforward maintenance.

Ergonomics: For extended use, consider grip comfort and trigger action. Well-balanced guns with smooth trigger operation reduce hand fatigue during prolonged application work.

Safety Information

Always wear safety glasses or goggles to protect eyes from accidental foam discharge, and disposable gloves to prevent skin contact with uncured polyurethane foam. Work in well-ventilated areas as expanding foam releases isocyanates during curing, which can irritate respiratory systems. For enclosed spaces, consider appropriate respiratory protection in accordance with COSHH regulations. Never point the gun at people or animals, and protect surrounding surfaces with masking tape and dust sheets, as cured foam is extremely difficult to remove. Store cartridges and guns away from heat sources and direct sunlight.

Frequently Asked Questions

How do I clean my expanding foam gun?

Clean immediately after use by removing the empty cartridge and attaching foam gun cleaner to the basket. Discharge cleaner through the gun until it runs clear, then wipe the nozzle and basket threads. Never allow foam to cure inside the gun, as this will render it unusable.

Can I leave a foam cartridge attached between uses?

Yes, this is a key advantage of foam guns. You can leave a partially used cartridge attached for several weeks, as the gun mechanism seals the cartridge and prevents curing. Clean the nozzle tip before storage and check operation before your next job.

What's the difference between gun-grade and standard expanding foam?

Gun-grade foam comes in larger cartridges (typically 750ml) that screw onto foam guns, offering better value, more precise control, and higher output than standard aerosol cans. Gun-grade formulations provide more consistent quality and expansion characteristics, making them more economical for professional or frequent use.