The house Mears built from videos and carpet tiles

A house built almost entirely out of rubbish, including toothbrushes, video cassettes and carpet tiles, will open its doors to the construction industry next month for a half-day seminar explaining its construction.

The Waste House, located in Brighton, was designed by architect BBM and built by main contractor Mears Group in collaboration with the University of Brighton and recycling website Freegle. Roughly 85% of the building’s structure is made up of discarded materials, including timber, rubber and plastic, which has enabled it to achieve a negative carbon footprint, yet also gain an Energy Performance Certificate “A” rating.

The seminar on 13 June, entitled Waste Not Want Not, will be hosted by sustainable building specialist The Green Register, along with members of the Waste House design team, who will discuss their experiences on the four-year project, as well as provide a guided tour and answer questions.

The Waste House is a prototype based on an earlier eco home, also designed by BBM, for industry green-guru Kevin McLeod and the Grand Designs TV programme. It is similar in size to a detached house and will function as the university’s sustainability learning centre, accommodating a large teaching room, an entrance hall and staircase and a disabled-access toilet on the ground floor and an open plan combined teaching area and kitchen on the first floor.

Video cassettes have been used as insulation in the walls

The building makes use of more than 2km of decking, 2km of timber, and 2,500 nuts and bolts, taken from structures dismantled after a previous Brighton Festival. These were re-used to build the structural columns and beams and timber cassette floors. Builders merchant Travis Perkins provided 350 sheets of plywood, damaged during transit, to create the walls.

The walls were filled with a range of unconventional insulation materials, including more than 2,000 toothbrushes, as well as video cassettes, floppy disks, CD cases and old denim jeans.

“Thermal performance of all the materials used in the building will be tested over the coming months to determine whether they are an effective form of construction,” said David Pendegrass MCIOB, at Mears Group, who managed the build process and also oversaw the many University of Brighton and City College students and public volunteers who have helped build the house since work started on site in April 2013. “We are optimistic that the video cassettes will perform well, as a previous office block in China used these in a similar way.”

Carpet tiles were used for the cladding

The roof is made up of a single large sheet of EPDM rubber made from recycled Pirelli car tyres, and the rainscreen cladding comprises 2,000 carpet tiles discarded by a nearby office. Although these were inverted to create a weather-resistant rubber outer layer, a conventional vapour barrier was still required to boost performance.

Other materials that could not be sourced as waste were donated by product manufacturers, such as three rooftop windows from Velux, windows and doors from a Russian manufacturer and a heat recovery unit from Vent-Axia.

Heating and cooling performance was enhanced by incorporating a large amount of thermal mass, including a rammed-earth central wall made of chalk, plus discarded Poratherm clay blocks and Termalite blocks stacked loose within the walls.

“Part of the idea of the project was to try to assess the value of the materials people typically throw away without thinking about the consequences,” said Pendegrass. “For example, plastics cannot be disposed of environmentally, and are typically either incinerated or go into landfill. A lot of plastics went into the walls to see if they have a value as insulation.”

Working with mostly salvaged materials and non-professional construction workers posed a number of challenges for the project team, he added: “We were essentially coming up with a new form of construction, which made early planning all the more important as you really need to know what materials you have available to build with before you can design anything. And because all the labour was voluntary it was a case of train as you go, instructing people on the day when they turned up to provide support.”

The Waste House project is due to launch on 10 June 10 and the Green Register seminar will run from 2-5pm on 13 June. Places cost £59 for Green Register members, or £85 for non-members. Visit www.greenregister.org.uk for more information and online booking.