RENDERING FOR EARTHEN BUILT AND EARTHEN COVERING Sussex Coast College Hastings students workshop June 5th to 7th Parc des Marais du cotentin et du Bessin Pascal Lebas

Role of rendering: Applying the rendering on the wall can have several functions:  It protects more or less exposed external façades against bad weather and allows the maintenance which is easier and cheaper than the reparation of a damaged wall  It insulates thermally and acoustically and allows regulating the moisture between the interior and the exterior. Its thickness and its composition can replace a traditional insulating material.  It embellishes both the interior and the exterior and decorates them with various shapes, colours and textures. March 16

Composition: In order to understand the rendering: all rendering is made of the same basic ingredients which are  aggregates which constitute Mortar framework, like sands (crushing, river or sea sands after washing)  binders which reinforce the framework by sticking aggregates together  a diluent which allows the workability of the mortar the same way as water March 16

BASIC MORTAR Binders Earth Lime Plaster Cement + Aggregates Sand Gravels Shives and hemp fibres Wood chips + Water Optimised mortars Fibres Horsehair Cow hair Shives Hemp fibres Cut straw Hay Etc… Adjuvants Linseed oil Beeswax Milk Egg Alum potassium Etc… March 16

Variation of mixture in accordance with the nature of the earth Clay earth Lime earth % Sand Lime ( type CL 90) March 16