Assessment of natural aging and ecological surface treatments in earth renders


  • Tânia Santos CERIS – Civil Engineering Research and Innovation for Sustainability e Departamento de Engenharia Civil, Universidade NOVA de Lisboa
  • Ricardo Gomes Departamento de Engenharia Civil, Universidade NOVA de Lisboa
  • Paulina Faria CERIS – Civil Engineering Research and Innovation for Sustainability e Departamento de Engenharia Civil, Universidade NOVA de Lisboa



Mortar, In situ characterisation, Durability, Natural exposure, Clayish earth, Coating


In conservation, earth renders can be used as sacrificial coatings. However, earth presents vulnerability when in contact with water. The application of ecological surface treatments on earth renders can be of great relevance, ensuring their durability while increasing eco-efficiency and extending its range of applications. The behaviour of a ready-mixed earth render applied in situ, on adobe and concrete block masonry experimental walls exposed outdoors with protection, and under controlled laboratory conditions, on hollow bricks, was evaluated after four years. Several superficial treatments were applied on the renders: linseed oil, mucilage of aloe vera and pasta and rice cooking water. The renders were characterized by non-destructive tests. The surface treatment with linseed oil presents good results and improves the durability of the earth render, giving it adequate protection against natural degradation.


Received: 2019-3-1
Revised: 2019-4-17
Accepted: 2019-10-20
Online: 2020-4-15
Publication: 2020-11-27


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How to Cite

Santos, T., Gomes, R., & Faria, P. (2020). Assessment of natural aging and ecological surface treatments in earth renders. Conservar Património, 35, 31–44.




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