Abstract:
This paper addresses the study of renders and plasters’ physical and mechanical characteristics
from selected buildings awarded during the 20th century with a renowned architectural
prize in Lisbon, Portugal. The characterisation was done to understand mortars’ physical and mechanical
properties and their evolution during the 20th century. These characteristics will also help
determine compatibility requirements for future conservation and restoration interventions. Since
these buildings have a heritage great interest status, the need to preserve them is a paramount issue.
Fifty-three samples from nine case studies were studied via capillary water absorption, drying rates,
open porosity, dynamic modulus of elasticity, and compressive strength. There were limitations in
sample collection due to the buildings being in service and technical constraints regarding sample
quantity for testing and separating layers of the multi-layer mortar system. Nevertheless, the results
showed different ranges of quantitative values for these tests, whether the mortars were lime, gypsum,
cement-based or had lime–cement blended formulations.
