Clean and green future with soap-based home insulation

University of Salford researchers are set to clean up thanks to a cheap, environmentally friendly alternative to petroleum-based insulation for homes – blocks of soap.

Increased pressure to make buildings more energy efficient is leading to greater demands for insulation to be added in order to conserve heat, but most insulation products used in buildings are petrochemical materials such as polystyrene and polyethylene. Manufactured from crude oil which is in finite supply and subject to rising prices, the insulation also comes with a significant carbon footprint caused by extraction and refining.

Instead, researchers Dr Yusuf Arayici and PhD candidate Lee Read have patented the idea of using waste oils such as animal and vegetable fats to produce soap which can be cut into blocks to provide insulation.

The majority of synthetic insulation is difficult to recycle and is sent to landfill sites when it is no longer needed. This type of insulation degrades slowly and leaches toxins into the soil as it does so. While wool, straw and other natural insulations are also used, they are only a niche part of the market and are much more expensive than the synthetic alternatives.

Using traditional soap-making methods the researchers created a variety of types from waste beef, pork, vegetable and engine oil. This was added to lye made from hardwood ashes and allowed to form into solid blocks. It was found that the animal and vegetable fats set best.

It was also necessary to reduce the weight of the blocks, so straw was introduced to make them lighter. In another experiment bubbles were added using the same method used in making chocolate bars like Wispa and Aero.

The team has now been able to prove that it is possible to make soap from recycled materials and that it is strong and light enough to provide insulation. The next phase is to test variations of design within the university’s labs in order to find the most effective methods.

Dr Arayici explained:

“By using reclaimed materials in the making of this soap we are reducing the amount of plastics going in to landfill. Insulation does reduce carbon emissions, but by making it out of oil we take a huge chunk out of the overall savings.

“There’s a lot of work to be done on making soap an effective material, but if we can design a good product that can be made cheaply, then we can insulate our homes without damaging the environment.”