EVER BUILD Ever Flex CONTRACT AC50 Acoustic Sealant & Adhesive 380ml

EVER BUILD Ever Flex CONTRACT AC50 Acoustic Sealant & Adhesive 380ml is a professional-grade, permanently flexible water-based acrylic sealant and adhesive from Sika Limited, engineered specifically for acoustic sealing and plasterboard bonding in dry lining applications. Independently tested to BS EN ISO 140/3, it forms a durable, airtight acoustic barrier that significantly reduces sound transmission through walls, floors, and ceilings — making it the go-to choice for contractors, dry liners, and serious DIY soundproofing projects.

Key Features and Specifications

• Format: 380ml C4 cartridge — fits any standard 380ml sealant gun
• Composition: Water-based acrylic; solvent-free and low-odour
• Flexibility: Permanently flexible after cure — will not crack or shrink with building movement
• Grab: High-grab formula suitable for walls, ceilings, and overhead applications
• Colour: White
• Tack-free time: 15–60 minutes
• Full cure time: 1–5 days (dependent on joint thickness and conditions)
• Application temperature: Do not apply below 5°C
• Storage: 12-month shelf life; store at 5–25°C, protect from frost
• Solid content: Approx. 80%
• Certifications: BS EN ISO 140/3 | EN15651-1:2012 | EN13963:2005
• Properties: Mould resistant, non-flammable, overpaintable, easy clean-up with damp cloth
• Manufacturer: Sika Limited (Everbuild), Leeds LS9 0SW

Applications

• Sealing gaps between plasterboard walls, floors, and ceilings to create a continuous acoustic barrier
• Bonding plasterboard to plasterboard, timber studding, metal studding, and direct to blockwork or masonry
• Sealing and bonding kraft-lined insulation boards in dry lining systems
• Sealing around partitioning systems, socket boxes, and service penetrations for airtight acoustic performance
• New-build and refurbishment soundproofing — suitable for both first-fix and retrofit installations
• Note: intended for internal use only; not suitable for prolonged external exposure or contact with bituminous materials.

Why Choose This Product

The Everbuild Everflex AC50 is widely regarded as the industry standard for acoustic sealing and plasterboard adhesion in the UK trade. Its dual-purpose formula eliminates the need for separate sealant and adhesive products on site, saving time and cost. The permanently flexible, non-shrinking formula accommodates structural movement without breaking the acoustic seal, while the water-based acrylic composition keeps the working environment safe and clean. Overpaintable once cured, it leaves a professional finish with no reworking required.

Delivery in and Around London

We deliver the EVER BUILD Ever Flex CONTRACT AC50 Acoustic Sealant & Adhesive 380ml to all London boroughs, including Croydon, Lewisham, Southwark, Camden, and Hackney, as well as Greater London areas such as Enfield, Bexley, Redbridge, and Barnet. We also supply to the surrounding counties of Kent, Essex, Surrey, and Hertfordshire. Single cartridges and trade quantities (boxes of 12) are both available — ideal for contractors and fit-out teams working across multiple sites.