The story of Earth Lab

Glulam Beams

A natural alternative to steel or bricks, we chose ‘glulam’ beams – literally ‘glued laminate’ – to form the structural elements of the walls and roof.  Glulam is a strong and attractive material comprising wood layers, which can be customised to unusual shapes and designs.

All of the straight glulam beams have been made by a German glulam manufacturing firm, specialising in the mass production of standard spruce glulam. For this type of product they have very energy efficient machinery and manufacturing systems, which goes a long way to offsetting the carbon emissions of the haulage. The curved beams were manufactured by UK specialist Buckland Timber, based in Devon. The raw glulam materials are machined by hand, before fitting metalwork as necessary and sending them to site.

All of the timber used to manufacture the glulam beams in this project was sustainably grown PEFC certified spruce of Scandinavian origin. The energy used to fabricate a glulam beam is 5-6 times less than a steel or concrete beam of the same mass and length.

Rammed earth wall

One of the prominent features of the project is the ‘rammed earth’ wall that is constructed inside Earth Lab. Rammed earth walls act as a natural heat and humidity regulator, which is extremely useful for spaces with significant flows of people. Advice was been sought from rammed earth specialist Rowland Keble, who was most significantly involved in the Eden Project in Cornwall. The materials for the wall have been carefully selected from spoil arising from the reduced level and foundation excavations on the site, mixed with soil from archaeological excavations at Little Wittenham.

A small demonstration section was been erected outside the Earth Trust Centre, in order to test the suitability of the local materials. This section remains in place to give visitors an insight into the construction process.

Straw insulation

‘Modcell’ is a prefabricated cell that contains shredded and compacted straw for insulation. The cells are constructed from a timber frame, insulated with straw and clad to the faces with plywood. Straw has excellent thermal insulation qualities, as well as being 100% renewable material with carbon sequestering properties. The frames are constructed using FSC or PEFC timber sourced in the UK.

Waste generated during the manufacturing process is also reused. Trimmings from the straw bales can be used as animal bedding or turned into biomass fuel along with the timber off cuts and used in the manufacturer’s biomass boiler. Being prefabricated, journeys to site are minimised. Modcell deliveries were made on two vehicles and lifted into final position to reduce the labour force on site along with the noise and dust typically generated from traditional construction methods.

Wildflower roof

The roof of the Earth Lab is a true green roof with the ability to support wildflowers. It offers multiple benefits including habitat creation, increasing biodiversity, water filtration and creation, and carbon capture. Species are reflective of the wildflowers native to the area, and were introduced through a combination of plug planting and seeds.

Gateway to green spaces

Earth Lab was created in 2021 under Phase 1 of the Gateway Programme, our initiative to find new ways to welcome and excite people about the natural green spaces and heritage at Earth Trust. Our plans for Phase 2, continuing our journey to improve the facilities and accessibility at Earth Trust Centre are underway throughout 2023 onwards.