Cavity Closers

The simplest and most effective way to seal cavities around wall openings

PVC-U cavity closers with mineral wool insulation offer 60 minute fire integrity. Can be used in conjunction with any window or door material or system and is suitable for second fix applications and timber frame installation, the economical way to achieve building regulations compliance,


The rigid PVC-U profile encloses a core of CFC-free EPS insulation which forms a continuous insulated cavity closer preventing cold bridging. Supafix, available from Norman Piette, can be used with all types of door and window openings. These cavity closers overcome the traditional difficulties of closing cavities at wall openings by providing a simple and efficient solution to thermal bridging. Primarily designed for second fix applications and can be simply cut to length and push fitted into the cavity after the window or door opening has been made thus eliminating the need for cut blocks, bricks or special reveal blocks.

Supafix is available in a range of sizes to fit cavity widths from 50mm – 100mm, with sufficient design flexibility to tolerate rogue cavity widths, thus reducing time and cost on site.

Kingspan Thermabate Cavity Closer

A PVC–U extrusion with a fibre free, rigid thermoset insulation core that maintains continuous insulation around window and door openings. It is suitable for use with timber, metal or PVC window frames.

For further information on Cavity Closers, call us on +44 (0) 1481 245801 or email


Insulated Cavity Closers Datasheet

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