Renders are an important item in historical buildings and the need for their periodical
re-application is a basic conservation procedure. In modern times there has
been a trend towards the replacement of traditional pure lime mortars by new
formulations including Portland cement or hydraulic lime. Apart from those interventions
on specific and very important monuments, in which the use oftraditional
non-hydraulic mortars can be enforced, in most of the projects involving less than
first order magnitude heritage the use of some sort of hydraulic components is
becoming the rule rather than the exception.
The present paper describes and analyses the results of an experimental study with
ten formulations of current mortars - including some that can hardly be considered
as adequate conservation procedures - allowing a direct comparison in terms of
some of the most relevant characteristics
