Case Study: Aircrete blocks for an Efficient Self Build Home

When demolishing their family home in Bourne End, Buckinghamshire to make way for a new ultra energy efficient property the Thomas family were very particular when it came to specifying the correct products to use in the build.

It was decided early on in the process that the internal and external walls of the four double bedroom property would be built using H+H Standard Grade Celcon Blocks and Celcon Foundation Blocks with traditional mortar.

Why aircrete?

H+H aircrete was specified for one particular reason – its strong sustainability credentials. Not only does it provide first class thermal and acoustic insulation and contributes significantly to improving the air-tightness of a property, the material itself is manufactured from up to 80% recycled materials.

On top of this around 99% of all raw materials are sourced from the UK reducing the need for transportation around the country. The primary ingredient is pulverised fuel ash (PFA) which is a by-product from coal fired power stations, which would otherwise be sent to landfill.

H+H Celcon Blocks have the ability to help control the temperature of a room, an attribute that appealed greatly to Mr and Mrs Thomas. Being of a relatively high thermal mass, aircrete can control temperatures in a way non masonry materials cannot. It absorbs heat during the day and releases it at night creating a comfortable internal environment in the building.

Energy efficiency

Aircrete blocks have a low lambda value (the measure of thermal conductivity) and provide excellent insulation due to the millions of tiny non-interconnecting cells that make up the structure of the blocks, helping to reduce heat loss.

To further improve the energy efficiency of their house the couple opted to finish the external walls with 10mm external wall insulation above DPC and 80mm below. This resulted in a minimum U-Value of 0.24W/m2K and a ‘B’ rating in the energy performance certificate.

The perfect finish

“This was the first time I had built a house with external wall insulation, although I am very familiar with block-work building,” says the contractor Chris Page. “The single skin went up very quickly and I am very pleased with the end result. I would love to build another house like it.”

The new house ticks all of the boxes for the family: large living spaces and a light open plan feel “My favourite thing about our new home is the comfort factor. It is so warm and homely; there are no cold spots at all,” says Mrs Thomas. “Despite being bigger than our old bungalow it uses less energy. We really enjoy living here.”

For further information on H+H, its products and services, visit www.hhcelcon.co.uk. You can also follow them on Twitter @celconblocks, like their Facebook page ‘H+H Celcon’ or watch videos on the YouTube channel ‘hplushuk’