Exterior Archives - Darren Slater Painter

To ensure the longevity of a paint system that is exposed to extreme elements, regular inspections should be carried out and general maintenance made to any areas that are damaged or under stress.

There are several key things to look for when preparing a surface for repainting:
•   Is there mould present? A quick wash with water will not remove spores or small particles, a chemical treatment is required. Moulds can regrow underneath new paint films popping them off the surface.
•   Is the surface chalky or dirty? Proper cleaning involves both washing and rinsing. Cleaning solutions bind up dirt and small particles so that they are washed away from the surface, rather than just moved around.
•   Are there old sealants and puttys? Failed sealants and puttys should be removed and replaced with new materials. Adhesion tests should be carried out on any previously painted areas. • Are there cracks, loose render or exposed rebar? If your building is in a seaside location these are some of the issues you can be faced with. These issues need to be dealt with quickly as allowing water ingress will increase the amount of damage and therefore repair work needed. Wind driven rain, especially with a high salt content erodes the weather protection of the building.

External paint coatings don’t last forever, and recoating must be carried out routinely to maintain decorative and weather-resistant properties. How long external paint will last depends on the:
•   quality of surface preparation and condition of the old paint. Paint will last better when the old paint is still in a reasonably sound condition and the surface is well prepared for the new paint
•   quality of the paint used. Typically, you get what you pay for – extremely cheap paints are likely to deteriorate faster than better quality (more expensive) paints
•   amount of sun shining on it – paint on the side of a building that gets less UV light exposure and will last longer than paint on a full exposed side
•   colour – lighter colours tend to last longer than darker because they absorb less heat, so expand and contract less
•   size and type of material under the paint. Paint properly applied to cement-based materials tends to last longer than paint on timber
•   cleanliness of the painted surface – wash down often to remove airborne chemicals and dirt from the surface
•   number of coats applied
•   underlying colour – applying a dark colour directly over a light one can cause a previously sound paint to lose adhesion because of the higher surface temperature.