14 July Preparation Is Ninety per Cent of an Exterior Finish
The difference between exterior paintwork that lasts eight years and paintwork that fails in two is almost never the paint. It is what happened to the surface before the first coat went on. On the Dorset coast, where salt air, driving rain and strong summer sun all work on the same elevation, that preparation matters more than most people expect.
Here is the sequence we follow on every exterior job, whether it is a bungalow in Winton or a three-storey block in Boscombe.
Start with a Proper Wash Down
Render and masonry collect algae, dust and salt deposits that stop paint bonding. Everything gets washed down and treated with a fungicidal solution, then left to dry fully. Painting over a damp or dirty surface is the single most common cause of early failure.
Deal with Cracks Before They Spread
Hairline crazing can usually be bridged with a flexible coating, but anything wider gets cut out, filled and stabilised. Ignore it and water will keep getting behind the render, which pushes the new coating off from underneath within a season or two.
- Remove all loose and blistered coatings back to a sound edge
- Stabilise chalky or powdery render with a penetrating primer
- Repair and repaint rainwater goods while the access is up
- Use a breathable system so trapped moisture can escape
Choose the Weather, Not Just the Colour
Most exterior systems need surface temperatures above 8°C and a dry spell either side of application. In practice that means booking exterior work between spring and early autumn in Dorset, and building a little contingency into the programme for rain. We would rather move a day than rush a coat on before a downpour.