Case Study

Cementaid (UK) Limited

Executive Summary

Success is often attributed to innovation and research and this is certainly true for Cementaid (UK) Limited whose founder invented and delivered Hydrophobic and Pore-blocking Ingredients (HPI) to structural concrete.  The famous HPI called Caltite is today installed in 38 countries around the world.

About Cementaid (UK) Limited

The Cementaid Group was founded by Peter Aldred, *DFC, in 1954.  Peter was a decorated airman of the Second World War who on his return to civilian life started a concrete admixtures business.  His interest and research into advanced concrete technology led him to being recognised as one of the Industry’s pioneering developers of admixtures and additives for enhanced concrete performance.

Caltite was launched in 1958 and to this day the proven formulation has remained unchanged.  2018 is the Silver Anniversary of the BBA Agrément Certificate 93/2888 for Caltite.

About the Product

Cementaid (UK) Limited’s Caltite is an aqueous, hydrophobic liquid incorporating pore-blocking and corrosion resisting components, for use in concrete mixes to provide watertight concrete for basements, roofs, swimming pools, tunnels, and culverts, without the requirement for additional applied protection.


Gaining acceptance with Specifiers, Structural Engineers and Architects is always a challenge.  So when approached by an architect for a project that was in a conservation area and wasn’t covered by building regulations the team at Cementaid (UK) Limited were delighted to be involved.

The Results

The Amphibious House, Marlow, Buckinghamshire.

The first ever “Floating” House in the UK was built on the flood banks of the River Thames in Marlow and completed in 2014. The amphibious performance of the house is made possible by the use of Cementaid’s Caltite additive to provide a truly waterproof concrete structure.

The Floating House, which is situated in its own “Dock”, is designed to allow the natural movement of rising floodwaters over the site. The dock extends to 5 meters below ground level. Four tall galvanised steel “dolphins” were installed around its perimeter to guide and stabilise the house structure during floatation.

The Caltite concrete basement slab and retaining walls of the house structure itself were then constructed inside the dock. The dock structure is designed to permit rising floodwaters to enter into the approximately 600mm space between the dock and the house basement, allowing the entire house to rise and float when sufficient flood water has entered into the dock. The house is designed to be able to rise up to two and a half metres, based on worst-case scenario flood predications from the Environmental Agency and some additional tolerance for climate change.

This was only possible by the use of completely waterproof, dry and corrosion resistant concrete achieved by the incorporation of Caltite into the concrete mix.

Working with the BBA

Maintaining the BBA Agrément Certification requires dedication from the team at Cementaid (UK) Limited and whilst the continued monitoring is timely it ensures the product remains fit for purpose.

How Agrément Certification has helped

James McDonald, General Manager of Cementaid (UK) Limited, commented:

“British Board of Agrément certificates are recognised in many countries as proof of quality and efficacy of products and this has been a great help to us in promoting the use of Caltite around the world”.

For more information please contact:

Cementaid (UK) Limited
1 Baird Close,
West Sussex,
RH10 9SY

Tel: +44 (0) 1293 653900