The Thermo-loc Platinum Multi Cavity Closer is a high-performance solution designed to prevent dampness and eliminate cold bridging around external doors, windows, and sills. Ideal for both professional tradespeople and DIY projects, this smart and efficient product is a must-have for meeting modern building standards with ease.

Suitable for cavities ranging from 100mm to 150mm, this 150mm cavity closer features pre-cut grooves, making it simple to adjust and cut to your required size on-site, saving time and reducing waste. Whether you're working on new builds or refurbishments, this cavity closer adapts easily to the task at hand.

At 2.4m in length, it delivers reliable thermal insulation while sealing cavities to protect against heat loss, cold ingress, and moisture. It's the ideal solution for creating a clean and secure seal at window jambs, door reveals, and sills.

Looking for a smaller size? We also stock an option for cavities from 50mm to 100mm. Whether you need cavity closers in 150mm or 100mm, Mitcham Builders Merchants has you covered.

As South London's largest independent builders merchant, we make it easy to get what you need. Order online with fast same or next-day delivery available depending on your location, or visit us in-store at one of our branches to see the full range. Our expert team is always on hand to help you choose the right product for your project. From cavity closers to concrete, we stock all your building supplies under one roof, making it easy to complete your project with confidence.