On 8th February 2018 A&DS collaborated with the Scottish Ecological Design Association to present an evening on strawbale construction. Practitioners with experience of designing and building with straw bale presented a wide variety of built examples and straw building techniques Here are some of the things we learned–
1. It’s nothing new
In 1885 the first straw baler was invented and shortly after that settlers in Nebraska started using straw for building. Eileen Sutherland from the School of Natural Building presented a variety of buildings from simple houses in Nebraska to the Burritt Mansion in Alabama.
2. Structurally speaking…
There are four different methods of employing strawbale construction. These are:
- Load Bearing
- Infill – in conjunction with a timber frame
- Hybrid – a mixture of both hybrid and load bearing
3. Strawbale Council Houses?
Straw is not just the preserve of one off self-build houses – the first strawbale council houses were built by North Kesteven District Council in Lincolnshire in 2009.
4. You need to raise the roof
As strawbale construction requires a dry (covered) environment for construction it is common for the roof to be in place on props and then dropped onto the loadbearing strawbale once the walls have reached the correct height. Architect Sam Forster explained that this was the method used in the building of The Piggery new build house.
5. Three is the magic number
When it comes to finishing straw buildings, that is:
- Three coats of clay in the inside
- Three coats of lime on the outside.
6. It’s not just a new build scenario
Eileen Sutherland from the School of natural Building introduced the UpStraw project an EU funded Northwest Europe project with partners in the UK, Belgium, Germany, France and the Netherlands. The project will primarily raise awareness and knowledge of strawbuilding while also producing one example public building in each participating country. The Dutch intervention will retrofit a sports hall in Tilburg with a straw outer skin.
7. Right Angles are the right angles
When building with straw bale follow the shapes and dimensions of the bale, 90o is the best angle to employ between walls because cutting the bales to other angles is not easy.
8. It has Fire Resistance
Tests carried out by BRE in 2004 confirmed that strawbale construction can withstand fire for 2 hours and 40 minutes.
9. Forward Planning is required
In presenting the Tullis Russell Environmental Education Centre in Glenrothes, Fife Richard Atkins, Architect confirmed that you have to source the strawbales for construction the year before and store them until the building starts onsite.
10. Information on strawbale building is readily available
Eileen directed event attendees to a number of resources and networks on building with straw including:
The training program from the European Learning Partnership for Professional Training in Straw Bale Building.
The Speakers at the Event were:
Eileen Sutherland MBA FRSA
Partner and Director of Business Development in Straw Works, and teacher of several courses. Eileen has been involved in establishing the Straw Works School of Natural Building and pioneered the building of the first straw bale property in Bulgaria.
Sam Foster RIBA FRIAS
Principal of Sam Foster Architects, a practice specialising in ecological design and a focus specifically on creating truly green buildings and sustainable spaces. Experienced lecturer on sustainable practice for conferences, and deliverer of lecture programmes for Local Authorities and Universities.
Richard Atkins RIBA FRIAS
Chartered Architect who designs sustainable buildings, advises clients, government and stakeholders of companies in energy efficiency whilst being a current Director of SEDA. Richard also played a key role in the publication of SEDA’s latest book 100 Sustainable Buildings.
Image: Sam Foster Architects