Kingspan Cavity Closers

Kingspan offers a range of high-performing cavity closers that are designed to meet various building needs and specifications. Their products typically emphasise thermal efficiency, ease of installation and long-term durability.

Kingspan places a strong emphasis on innovation and sustainability. It has committed to significant sustainability goals, aiming to reduce its environmental impact. This includes using renewable energy sources and reducing carbon emissions in its production processes.

Cavity closers are integral components used in the construction of cavity walls, particularly within the frames of windows and doors. These closers serve multiple essential functions: they help to mitigate condensation, reduce thermal bridging (cold bridging) and prevent the growth of mould. By doing so, cavity closers enhance the overall energy efficiency and structural integrity of buildings.


Kingspan Kooltherm Cavity Closer

  • Material Composition: PVC-U extrusion with a rigid thermoset insulation core.
  • Thermal Conductivity: 0.022 W/mK.
  • Range of Sizes: Available in thirteen sizes, ranging from 50 mm to 150 mm.
  • Extendable Width: Features jointing clips that allow sections to be joined, extending use for cavity widths up to 300 mm.
  • Compatibility: Suitable for use with timber, metal or PVC window frames.


Kingspan Kooltherm Cavity Closer PLUS

  • Custom Configuration: Prefabricated into a U-shape to match specified opening sizes.
  • Made to Order: Tailored to individual project specifications.
  • Compatible Cavity Widths: Available for the same range of cavity widths as the standard Kingspan Kooltherm Cavity Closer.
  • Precision Fitting: Helps achieve accurate opening sizes for installations.

Kingspan Thermabate Cavity Closer

  • Material Composition: uPVC extrusion with a fibre-free rigid thermoset urethane (PUR) core.
  • Thermal Conductivity: 0.034 W/mK
  • Application: Maintains continuous insulation around window and door openings in masonry cavity walls.
  • Compatibility: Suitable for use with timber, metal or uPVC window frames.#

For quotations, product information or technical support please call us on 01773 590100 or email


Why choose a Kingspan Kooltherm Cavity Closer for your project?

Why choose Kingspan Kooltherm Cavity Closer for your project?
Kingspan Kooltherm Cavity Closer (KKCC) is an ideal choice for construction projects, providing exceptional thermal insulation with a low thermal conductivity of 0.022 W/mK.

Versatile and environmentally friendly, the product suits various window and door frames, including timber, metal or plastic. Its durable design also simplifies construction by eliminating the need for cut bricks and blocks, saving time and money.

Can the Kingspan Kooltherm Cavity Closer be used with different window and door materials?

KKCC is compatible with various window and door materials, making it suitable for both new build and refurbishment projects. It can be used with uPVC, timber, metal and composite window frames. The product is available in thirteen profile widths ranging from 50-150mm, ensuring a perfect fit for different cavity widths and construction requirements.

A line of compatible accessories, including Jointing Clips, Jointing Strips and Optional Fixing Ties provides flexibility in design options and efficient installation.

How does Kingspan Thermabate Cavity Closer prevent condensation and mould growth?

The Thermabate Cavity Closer features a core of rigid thermoset urethane (PUR), which is known for its excellent insulating properties. This core effectively reduces thermal bridging by retaining more heat at window and door reveals, thereby minimising the risk of condensation on these typically colder surfaces. Additionally, Thermabate acts as an integral damp proof course (DPC), preventing moisture ingress around openings and reducing the likelihood of mould growth in these areas. Together, these features provide a durable and mould-resistant solution to traditional methods of closing cavities, addressing condensation concerns and enhancing the longevity of building materials.

What is the difference between Kingspan Kooltherm Cavity Closer and Kingspan Kooltherm Cavity Closer PLUS?

The main difference between Kingspan Kooltherm Cavity Closer and Kingspan Kooltherm Cavity Closer PLUS lies in the installation and design. The PLUS version consists of pre-formed sections assembled into a frame, reducing both labour and installation time.

KKCC PLUS shares the same profile widths as the standard Cavity Closer and is manufactured off-site to precisely match specified opening sizes. It’s compatible with various window frames, using either an insulated lintel or a KKCC section at the head.

Are Kingspan Cavity Closers environmentally friendly?

Kingspan is committed to environmental sustainability, particularly evident in their range of cavity closers. As part of their “Planet Passionate” initiative, Kingspan aims to meet sustainability goals by 2030, focusing on using renewable energy, reducing carbon emissions, promoting circularity and managing water resources responsibly. Products like the Kooltherm Cavity Closer are a testament to this commitment.

They are constructed with a uPVC J-section and a high-performance, fibre-free rigid thermoset phenolic insulation core, utilising a blowing agent with zero Ozone Depletion Potential (ODP) and low Global Warming Potential (GWP). These materials and manufacturing processes are designed to enhance thermal efficiency while aligning with Kingspan’s dedication to reducing environmental impact across their product line.

Is Kingspan Kooltherm Cavity Closer fire rated?

The Kingspan Kooltherm Cavity Closer itself does not have a specific fire rating. While Kingspan products are designed to meet high standards of safety and performance, including considerations for fire safety in many of their products, this particular cavity closer does not come with an independent fire rating certification.

For applications where enhanced fire performance is necessary, it is important to consult with us directly to discuss solutions or additional measures that can be implemented to meet fire safety requirements.