London Stone Conservation offers several methods to sensitively clean the fabric of a building, in-line with approaches to conservation approved by Historic England. These include:
DOFF & Thermatec Cleaning: Using steam (superheated water) and controlled pressure to carefully lift staining, friable materials (paint) and other organic contaminants from the surface of the masonry.
Torc & Jos: A light abrasive system, that combines organic compounds, pressurised air and water to gently remove carbon staining and sulphation crusts from stone and brickwork. This system utilises a swirling vortex washing action, delivered through a ceramic nozzle, gradually removing staining from affected areas of masonry without damage to the substrate.
Poultices: a chemical, non-aqueous cleaning process that can be specifically designed to target contaminants within the stone surface, and successfully draw out soiling without over saturating the stone with moisture.
Soot Washing: in some cases the overall appearance of a building has suffered atmospheric staining. Historic England’s conservation philosophy acknowledges that this original patina forms part of the historic context of a building and as such, needs to be preserved. In cases where the majority of the façade is blackened by historic staining, any repairs and replacements can be soot washed by hand to achieve a close match in the appearance of the original stained façade