Materials

Timber Frame

The FSC timber frame, manufactured by Advanced Timber Frames, is the load bearing structure of The Renewable House and significantly reduces embodied energy compared to non-renewable equivalents, meaning lower emissions over the lifecycle of the house. The design of the frame is being developed to reduce the timber content by maximising composite construction interaction with internal boarding and Hemcrete®.

Walls

The walls utilise Hemcrete®, a material manufactured by Lime Technology that is renewable and sustainable, as well as delivering high levels of insulation, airtightness and vapour permeability. The 300mm Hemcrete® wall delivers a steady state U value of 0.19 W/m2k and has been designed to achieve an airtightness of 2.0m3/(hr m2). The monolithic nature of Hemcrete® means this is easily achievable.

Hemcrete® is made from the core (shiv) of hemp plants and a special lime based binder (Tradical® HB); which together form a bio-composite building material. By using Hemcrete® TheRenewable House has locked 110 kg/m2 CO2 into its walls. Hemcrete® is mixed on site for fast track construction before being cast around the frame. An external finish of Limetec® render and an internal finish of Limetec® plaster completes the walls.

• High thermal, insulation and airtightness properties, reducing in-use energy consumption
• Locks CO2 within the wall construction
• Produced from renewable resources
• Offers a highly sustainable and fast track method of construction
• Cost effective when compared to conventional masonry
• Enough hemp to produce one house can be grown in just 14 weeks in one hectare of land

Windows

The use of renewable materials continues with the high-performance triple glazed timber windows from Jeld-Wen. The windows provide a U value of 1.3 W/m2K, and careful attention to detailing has minimsed conductivity. The style of the windows has a high percentage of glazing to maximise daylight.

Thermafleece^TM loft insulation

The insulation is Thermafleece^TM, which is made from the wool of British hill sheep. Natural insulation doesn't mean sacrificing performance for principles. It can at least match the market-leading mineral materials in terms of providing effective insulation. Natural materials can also offer several additional benefits including reduced greenhouse gas emissions, ease of handling and good acoustic insulation properties.

Roof

The roof tiles, manufactured by Sandtoft, have a high recycled content to minimise use of finite materials. The roof delivers an overall U value of 0.16 W/m2K.

Render & Plaster

The Baumit range of lime renders and plasters from Lime Technology is ISO 9001 certified and has European Technical Approval (ETA) demonstrating the company's firm commitment to quality. Lime Technology specifies Baumit renders and plasters as part of its walling systems because of the sustainable benefits of a breathable and flexible lime solution.

Baumit renders contribute to a healthy internal environment and are economic, practical alternatives to renders containing gypsum or cement that are less vapour permeable. Baumit renders and plasters are designed for spray or hand application as a two coat system. Suitable substrates include brickwork, blockwork or concrete