Cavity Closers

Cav 2

Cavity Closers provides an accurate template during construction insulates the cavity and ensures efficient window installation.

An indispensable part of any new build project, Profix manufactures the market leading BBA and NHBC accredited PVC-U Cavalok Cavity Closers which provides a rigid bricklaying template, window acceptor, damp-proof course and thermal break, all in one innovative, fast and easy-to-fit product. The closers are installed as the brickwork is going up and act as a former for the window. At a later date during the build process, the installation team will return and the windows are simply clicked into place in a matter of seconds.

In line with Profix’s Cav 1green credentials and commitment to the highest levels of sustainability within building, our cavity closers are made entirely from 100% post-consumer waste. Covering cavity widths from 70mm to 150mm, this unique innovation helps builders, installers and site teams save time, cost, energy and avoid inaccuracies and call-backs when putting volume windows in new build developments.

The Profix manufactured Cavity Closer insulates and seals cavities around windows and doors improving thermal performance and eliminating draughts. Its robust design can stand even the toughest site conditions and its universality means it accepts all window systems.


Standard Specification

  • Recycled profile extrusion
  • Acts as brickwork former
  • Closes 75, 90, 100, 115, 125 and 150mm cavities with flat, 33mm inset or check reveal (other cavity widths available upon application)
  • Eliminates moisture penetration around reveals
  • Prevents thermal bridging in accordance with Part L regulations
  • Assists Building Regulation compliance for air tightness
  • BBA & NHBC approved
  • Achieves thermal resistance path (0.45m2/KW)


Assessed to the thermal Path method (0.45m²/KW)