Coving
/ ˈkəʊvɪŋ /
Also known as: cornice, cove, ceiling moulding, plaster coving
Definition
Coving is a concave moulding fitted at the junction between the ceiling and the wall, covering the joint between the two surfaces and providing a decorative transition. A simple plain cove has a smooth concave quarter-round profile; more elaborate multi-profile versions with decorative detail are properly called cornice and are characteristic of period interiors. Materials include gypsum plaster (traditional, heavy, best finish), polyurethane foam (lighter, good detail, preferred for modern work), and polystyrene (cheapest, least durable). Fixed with proprietary adhesive, mitre-cut at corners. Edges are filled flush and decorated.
In practice
The most critical skill in fitting coving is the accurate cutting of mitre joints at internal and external corners. A standard internal corner is a 45-degree mitre on each of the two joining pieces; in practice, rooms are rarely perfectly square and the actual corner angle varies from 90 degrees. Using a digital angle finder to measure the actual corner angle and halving it for the mitre cut produces a much tighter fit than assuming 45 degrees. Proprietary coving mitre boxes are available for the most common coving profiles and simplify this process considerably.
Plaster coving in older properties can come away from the ceiling over time, particularly in rooms above bathrooms where moisture rises through the structure. The traditional method of cutting the falling coving back and re-fixing with new plaster and the original profile can be difficult to match. For large areas of failed plaster coving, it is often more practical to cut away the entire run, patch the ceiling and wall surfaces, and fix new polyurethane reproduction coving to match the original profile - polyurethane reproductions of most common Victorian and Edwardian cornice profiles are available.
See also