Lime was employed in the construction of nearly all old buildings in Britain. An understanding of this versatile natural material is fundamental to their conservative repair and long-term protection.
Lack of maintenance is a key reason why old buildings deteriorate. Maintenance essentially means preventing rainwater getting in where it can cause harm. Water is potentially most likely to enter through the roof, so putting right minor problems here before they worsen can avert the need for more extensive repair.
Historically, many building interiors were plastered with non-hydraulic lime, sand and hair (sometimes gauged with gypsum) or, alternatively, clay, a lime binder and reinforcement such as straw, concealed under a lime skim. Such plasters are applied directly to solid backings, such as masonry or cob, or flexible supports, including timber laths or reed. Lime or clay plaster can have a more pleasing character as well as offer better internal comfort and sound insulation than substitutes widespread by the 20th century.
Historically, many building interiors were plastered with non-hydraulic lime, sand and hair (sometimes gauged with gypsum) or, alternatively, clay, a lime binder and reinforcement such as straw, concealed under a lime skim. Such plasters are applied directly to solid backings, such as masonry or cob, or flexible supports, including timber laths or reed.