Materials and Structures

, 52:28 | Cite as

Recommendation of RILEM TC 243-SGM: functional requirements for surface repair mortars for historic buildings

  • Jan VálekEmail author
  • John J. Hughes
  • Francesca Pique
  • Davide Gulotta
  • Rob van Hees
  • Ioanna Papayiani
RILEM Technical Committee


Surface repair mortars are used for the compensation, or repair, of lost portions of surface materials in historic masonry buildings. It is recommended that their design and application should be performed in a wider context of conservation values related decision making, to prioritise preservation of original fabric, authenticity of approach and maintenance of integrity, and not just on technical principles alone. However, a technical context for their design does exist, that requires understanding of the properties of the substrate that they will be applied onto, and adherence to minimum aesthetic (colour and texture) requirements. The principles of physical, mechanical and chemical compatibility of repair apply and the attributes of the repair mortar should be carefully matched to the substrate alongside a sacrificial behaviour (not more durable than the material being replaced). Guidance is given on the design, application and the functional requirements that must be met when using surface repair mortars.


Surface repair Mortar Historic masonry Functional requirements 



The publication was written within the frameworks of RILEM TC 243-SGM with a special contribution of Dr. Ana Velosa of University of Aveiro.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© RILEM 2019

Authors and Affiliations

  1. 1.Institute of Theoretical and Applied MechanicsCzech Academy of SciencesPragueCzech Republic
  2. 2.University of the West of ScotlandPaisleyUK
  3. 3.SUPSILuganoSwitzerland
  4. 4.Department of Chemistry, Materials and Chemical Engineering “Giulio Natta”Politecnico di Milano and INSTMMilanoItaly
  5. 5.TNO, Delft & TU DelftDelftNetherlands
  6. 6.Aristoteles University of ThessalonikiThessalonikiGreece

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