Kooltherm K8 Cavity Board

Product Details

Kooltherm K8 Cavity Board is a partial-fill cavity wall insulation board with reflective facings on both sides. It is made for the cavity of masonry wall construction , double brick and brick veneer , where the board insulates while a clear residual cavity is maintained for drainage and ventilation.

The closed-cell structure matters in a cavity: the board does not act as a wick for moisture crossing the gap. Its board size is deliberately smaller than the soffit and lining boards in the range, sized to sit neatly between wall ties.

Best for K8

• Double brick cavity walls
• Brick veneer construction
• Blockwork cavity walls
• New residential and commercial masonry builds

Selecting the Right K8

Choose your thickness

K8 comes in 25 mm and 40 mm, giving declared R-values of R1.10 and R1.75. Your choice is usually driven by the cavity width, because a clear residual cavity has to remain.

Check your cavity width first

Board thickness plus the residual cavity has to fit the designed cavity. Measure before ordering , a board that closes the cavity is worse than no board at all.

Confirm board size

Board size is 1200 x 514 mm, sized to masonry coursing and tie spacing. Other dimensions are available on enquiry with minimum order quantities.

Why Builders and Designers Specify K8

• Sized for masonry cavity wall construction
• Closed-cell phenolic core that will not wick moisture
• Reflective facings to both faces
• Fibre-free core
• Available in 25 and 40 mm
• CodeMark certified
• Compliant with AS/NZS 4859.1:2018
• Global GreenTag GreenRate certified
• Australian made

Installation Notes That Prevent Callbacks

Working in double brick or brick veneer? Ask us to check thickness against your cavity width.

• Build boards into the cavity as the outer leaf goes up, retained against the inner leaf by the wall ties.
• Keep a clear residual cavity between the board face and the outer leaf. This is the detail most often got wrong on site, and closing the cavity compromises drainage and ventilation.
• Keep boards tight to one another and cut neatly around ties so there are no gaps in the insulation layer.
• Confirm residual cavity width, tie spacing and board thickness against your specification and the current Kingspan installation guide.

Does K8 fill the whole cavity?

No, it is a partial-fill board. A clear residual cavity is kept between the insulation and the outer leaf so the wall can drain and ventilate.

What thicknesses are available?

25 mm and 40 mm, giving declared R-values of R1.10 and R1.75 respectively.

Why is the board smaller than the other Kooltherm boards?

At 1200 x 514 mm it is sized to suit masonry coursing and wall tie spacing, so it builds into the cavity as the wall goes up.

Is it suitable for brick veneer as well as double brick?

Yes, K8 is used in both double brick and brick veneer cavity construction.

Will it absorb moisture in the cavity?

The core is closed-cell, so it does not wick moisture across the cavity the way an open-cell or fibrous product can.

Related Products

• Kooltherm K17 Insulated Plasterboard , insulate and line an internal wall in one fix • Kooltherm K10 G2 Soffit Board , soffit board for concrete ceilings • Kooltherm K10 G2W White Soffit Board , white finish for visible soffits • Kooltherm K10 PLUS Soffit Board , fibre cement face, Group 1 NCC classification