UK rammed earth guidelines, standards & resources

 

rammed earth is recognised in energy standards and specifications

 
   
 
 



 
   

         

Rammed earth doesn't have a British Standard or Eurocode yet. But it does have a well researched Guideline which has begun to act a a de-facto standard. Published in 2004 the Rammed Earth Design and Construction Guideline covers most of the aspects of design, testing and practical aspects needed to get a rammed earth structure through planning and building regs in the U.K. The Guideline has three sections for the architect, engineer and contractor, appendix A, B and C.

In the UK materials like rammed earth with no national standard has to be underwritten by an engineers design. This is the usual route to Building Regs. acceptance where the recognised regulators don't have a standard to follow. The engineers rely on material test results to understand the strength of a particular material and the Guideline appendix C to understand the specifics of designing for the material.

Likewise contractors not familiar with handling soil on site for earth building rely on the Guideline, for advice on material extraction, storage, mixing and placing. Appendix B also has a very useful specification which can be used and adapted for particular circumstances. Some expert consultation will help in this process but it is by no means unthinkable that an experienced builder could use rammed earth simply following the guideline.

Architects are not routinely trained to think about materials like

 

   
     
  The guideline is becoming the de-facto British standard for rammed earth  
     

earth, this is changing slowly but is by no means the norm. Most architects were trained before the introduction of the Guideline, but have access to the Rammed Earth in the National Building Specification (NBS), now an online tool from the Royal Institute of British Architects. The NBS have published a specification based on the Guideline, 25-00-70 150 Non- stabilized rammed earth wall system.

The NBS specification advises the architect that money for sample testing may be needed, as it would be with concrete. This practical kind of advice is an invaluable help to those who have used the material before as well as those who have not.

Rammed earth in BREEAM is also a very useful tool, putting the embodied energy of the material into context with other wall building systems. It allows designers to compare rammed earth using BREEAMs IMPACT system, calculating the parameters of energy used in each of the built elements.

There are other resources out there, the American ASTM Standard Guide for Design of Earth Wall Building Systems

     
       
    BREEAM energy standard lists rammed earth and chalk  
       
has been a welcome addition to the available information and standards for earth building. The forthcoming European training standard for earth structures will also give both designers and builders resources for training not previously covered.

For a very practical guide to building Rammed Earth Structures: a Code of Practice is the basis for a national standard in 15 countries in Africa. The tests and site advice are more hands on than the UK Guideline, it's a good place to start for a self builder.

And of course the existence of a national organisation co-ordinating efforts in the development of earth building has been and remains a fantastic resource.

   
         
    BREEAM rates rammed earth as an A+ material  
         
     
         
    The NBS specification for rammed earth, you need to be in the system to use this  

 

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