Clay Exterior Plaster
Life Cycle Transition
About the Product
homemade sample with linseed oil: Ramona schäfer, Mara Joergens
(Manufacturer: Lehmwerk Kleinfahner GmbH & Co. KG)Loam is a type of soil composed of sand, clay and silt. It is formed by the weathering of rock layers and is regionally available almost everywhere.
Air-dried components require less energy and thus cause fewer emissions than fired ones. Clay plasters are made of fat loam mixed with sand and organic fibres (e.g. hay). The bond is based on the clay contained in the loam. To apply clay plaster, clay mortar is thrown onto the wall in several layers, whereby the last layer is rubbed off again with a friction board and, if necessary, covered with thin lime slurry or similar to ensure better adhesion of the coating.
The clay plaster Universal Exterior by Kleinfahner is composed of natural, sieved raw clay and mixed-grained sand. The clay is quarried locally and air-dried. Regionally extracted straw (0–5 mm) is then added and mixed in the right composition. Final packaging is only done if the product itself is not collected locally and can be returned for a deposit. As a result, the production of the product amounts to a low primary energy consumption.
The application is mainly limited to indoor use; for outdoor applications, constructive moisture protection and/or sealing must be ensured. The coarse grain size leads to a high stability and allows the application as exterior render on façade surfaces (max. 1.5 cm per render layer; up to a total of 3 cm). Experience shows a weather resistance of at least 15 years. The product is also suitable as a clay mortar for laying light clay blocks. 15 kg is sufficient for a joint thickness of 10 – 15 mm for approx. 0.5 m2 of light clay blocks.
The clay plaster Universal Exterior can be recycled due to its natural composition. However, care should be taken that it does not contain any additional binders or stabilisers. For this purpose, the plaster is chipped off and mechanically crushed. When newly mixed with water, the recycled product is suitable as a base coat and to level out unevenness in the wall. A fresh layer of plaster should be applied on top.
Manufacturer: Lehmwerk Kleinfahner GmbH & Co. KG