ICF Construction

Our passive window sills are designed to work with Insulated Concrete Formwork (ICF) construction and are installed in the same way as a traditional concrete sill.

For most ICF builds we recommend our P4 passive sill – 225mm deep with a 25mm upstand. Our sills have excellent insulation value, this improves the overall insulation value of a building by reducing the cold bridging at the point where the sill and window meet. It also improves the overall performance of your window.

The Passive Sills P4 window sill is approximately 10% of the weight of a traditional concrete or stone sill and reduces the risk of manual handling injuries on site.

Our passive window sills are available in sandstone, white granite and grey granite effect finishes.

Why choose Passive Sills

Complies with all building regulations

Best for thermal efficiency

Super lightweight

Quick and easy to install

Lower carbon footprint

Best for manual handling

Competitive cost when installed

10 year warranty



Stone Finishes

Technical Model


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