The following interviews with master plasterer George O’Malley were recorded at the Provost’s House, Trinity College Dublin, on 24 May 2023. The purpose of this work is to document the insights of practicing craftspeople on historic interiors to better appreciate both the skill and the labour that went into creating them. In these pieces we hear about the value of the apprenticeship system, the importance of understanding lime plaster as a material, and the accretional tacit knowledge that underpins plasterwork when executed at the highest level.
While George was visiting, there was an opportunity to examine the attic space above the saloon which shows the wooden casing from which the plaster ceiling is suspended.
The coffered ceiling and its superstructure of structural carpentry reflect the interdependent skills of plasterer, carpenter and architect in creating the illusion of a solid classical vault. The three-coat lime plaster surface, modelled and enriched by hand, with additional use of wooden moulds, is fixed onto wooden laths, which are nailed to the timber framework.
The first application of rough plaster is applied over and through the laths to create a vital keying coat, onto which successively fine coats of plaster are applied. The great weight of the lime plaster would have been estimated by the plasterer and the architect while the timber framework, seated on the brick walls of the room and partially supported by the roof timbers, was created by carpenters likewise in consultation with the architect.
The use of animal hair as a binding agent can be seen in a loose fragment below, which shows clearly the method discussed here by George O’Malley.
For more insight into seventeenth and eighteenth century plasterwork, see plaster conservator Jenny Saunt’s ‘Drawing out a surface in lime and hair’ in Enriching Architecture: Craft and its conservation in Anglo-Irish building production, 1660–1760, edited by Christine Casey and Melanie Hayes, 262–288. UCL Press, 2023. For the wider European context, see Making Magnificence by Christine Casey (Yale University Press, 2017).