Get a whole year of cutting-edge eco-building news for just £24.00 pa.
Built upon 30 years of experience, this fabulous new medium will feature inspiring and in-depth articles on eco-building projects from across the spectrum and from all over the UK, most of which are written by the very people that designed or built them. Perfect for architects, builders, developers, self builders and anyone interested in keeping right up-to-date with green building trends and friends.
For subscription options:
please go here
|
|
|
The latest thinking on compost toilets |
|
 
|
|
|
|
6 Dec 2013, 9:17 PM
|
A sophisticated compost toilet was born in 2005 when long time AECB members, Nick Grant and Andy Warren decided to pool their experiences of composting facilities and respond to the growing demand for 'off grid' toilets.
|
Warren had developed a compact twin vault toilet with a novel system of urine separation. Grant also had many years of compost toilet experience. In building his home around one he had to solve the problem of odour and flies that plague so many systems.
Neither was confident to specify currently available commercial dry toilets but it was clear that one off design and manufacture was an uneconomic solution. So they decided to design a product that incorporated the lessons they had learnt and met their demanding performance requirements. Their company, NatSol, now supplies fully wheelchair accessible toilets nationally and has become the market leader with over 350 installations.
The pair have been involved with green building since the 1980s and the product reflects this. The twin vault chamber is made from glass reinforced cement (GRC). This is a high quality material with a design life of over 60 years. For practical reasons the first pedestals were made from GRC but they switched in 2013 to a unique stainless steel pedestal manufactured in-house. External timber cladding for buildings is Western Red Cedar sourced in Wales.
The two vaults provide for batch processing of solid wastes in a simple way This means that all the material to be removed has had plenty of time to compost.
Urine is the biggest challenge for compost toilets due to the ammonia and the sheer volume of liquid that must be evaporated or drained. Warren and Grant had not found evaporation to be reliable in the UK climate except for very low-use situations. Draining the vault from the base typically requires the chamber to be out of the ground, making level access difficult, unless a pump is used. By diverting urine to a shallow soakaway it does not enter the compost pile. The unique stainless steel urine diverting pedestal is common to all NatSol toilets and is the result of many years of development.
More about how this works and the story of its development can be read on the company website, there is even a little animation!
NatSol accessible toilets on remote sites are passively vented and need no water, no power, no sewage connection and no chemicals. If installed in a larger airtight building, rather than as a stand alone toilet, a I Watt fan would typically be used to assist ventilation.
Common sites for installation are allotments, rural churches, nature reserves, amenity sites, campsites and farm diversification projects.
The company also offers a compact version for private use away from the mains e.g. summerhouses and outbuildings. Timber buildings can be provided locally made with Welsh timber, or steel framed buildings with box profile cladding as standard options. Bespoke models are also available. You can, of course, design and build your own and utilise the toilet vaults as a foundation and floor. The website includes some examples and a Sketchup file to download.
|
|
|
|
