A Private House by Top Haven Properties

Ian Johnson MD Top Haven Ray Cllins from Wienerberger - Horton Northants

A property developer has been so impressed with Wienerberger’s precision clay block walling system and bricks that he used them to build his own home.

Project: Private House in Northamptonshire
Contractor: Top Haven Properties
Customer: Ian Johnson
Building size: 2,800 sq ft
Project length: Nine months
Porotherm Build: Two weeks
Time saving: Three times faster than traditional concrete block
Porotherm Block: PT100
Wall spec: 50mm partial fill insulation, 50mm air gap,
Brick: Wienerberger Terca Renaissance Multi facing brick
Wall thickness: 300mm
Thermal performance: 0.25W/m2K

“We are always on the lookout for innovative new construction methods and I was delighted to see Porotherm come to the UK after having seen it used so successfully on the continent for many years. The system has so many benefits for residential developers, especially as it achieves great thermal performance values which helps us to meet the Code for Sustainable Homes standard.” Ian Johnson, Managing Director, Top Haven Properties.


Ian Johnson MD Top HavenA property developer has been so impressed with Wienerberger’s precision clay block walling system that he used it to build his own home. Ian Johnson, managing director of Top Haven Properties, was one of the first contractors to trial Porotherm following its launch to the UK market in March 2009 and wanted to realise the benefits for himself. Mr Johnson used Porotherm for the internal walls and cavities of the 2,800 sq ft property which significantly increased the speed of the build over its nine-month programme, and enabled him to achieve latest sustainability standards.

The property, in Northamptonshire, is a five-bedroom dormer bungalow. The Porotherm PT100 block was used as the inner leaf of a cavity wall with a 50mm partial fill insulation, 50mm air gap, and finished externally with Wienerberger Terca Renaissance Multi facing brick. This inner wall was built independently of the outer facing brick due to the strength and stability of the Porotherm construction method which creates a watertight shell enabling internal fixes and external finishes to be carried out simultaneously, further shortening the build programme.

Porotherm is quick and easy
The system has many environmental benefits. It uses 95% less water on site than traditional blockwork and the Porotherm blocks include up to 30% recycled content. In addition, the wall construction will achieve a thermal insulation U-Value of around 0.25W/m2K, thereby reducing energy consumption. The scheme incorporates other sustainability measures including a modular roof system and a rain water harvesting system has been installed to feed grey water to the toilets.

Mr Johnson said that since completing the project his gas heating bills have dropped from around £125 per month in his previous home, to just £40 per month thanks to the increased thermal insulation created by Porotherm.

Although popular throughout Europe for more than 30 years, Porotherm was launched to the UK market at Ecobuild in March 2009. It offers a modern construction method with the reassuringly traditional values of clay. Wienerberger has now established a dedicated training centre at the Longbridge site of builders’ merchant and Porotherm system distributor EHSmith.

“My site supervisor agreed Porotherm offered the best option as it is light weight, easy to cut and, most importantly, simple to use with large sections laid far faster than traditional blocks. The team has achieved speeds up to three times quicker than traditional blockwork which meant I was able to move in far sooner than I might have done if we had gone with another product.” Ian Johnson, Managing Director Top Haven Properties.