Painters & Decorators

Choosing paint for an old building

Let the substrate choose the paint. Lime plaster and lime render need a vapour-open finish such as limewash, distemper or a mineral paint; modern vinyl emulsion and masonry paint seal them and cause blistering and damp. On external joinery and ironwork, linseed oil paint penetrates and stays flexible, whereas a hard modern film cracks and lets water behind it.

Take preparation seriously and slowly. Aggressive sanding, abrasive blasting and hot-air stripping all destroy historic surfaces and can ignite dust in old timber. Careful hand preparation, poultices and low-temperature methods take longer and preserve the substance of what is being decorated.

Assume lead paint on anything decorated before 1970. Sanding or burning it releases lead dust and fume; the safe route is controlled removal by a contractor who tests first and works wet, or leaving sound coatings in place and overpainting.

Ask to see comparable work. Traditional paints behave differently in application, coverage and drying, and their success depends far more on the decorator's experience than on the tin. Photographs of finished heritage projects say more than product literature.