HOW TO PAINT YOUR EXTERIOR WALLS
28th January 2018
If your exterior walls have been painted, then they will need to be maintained. This is a big job that requires a lot of planning and thought before you start to ensure that you have all the necessary tools and equipment before you start. A high level of surface preparation is essential if the job is going to look good and last a long time.
- If the surface is very bad then it may be necessary to wash some of it down first with a detergent solution to remove dirt, grease etc. Obviously this is not an easy thing to do on the outside of a house, but it will help give the best results. Rinse off with clean water and allow too dry.
- Carefully scrap back to a firm edge all areas of poorly adhering or defective coatings and rub down thoroughly to “key and feather” broken edges of existing coatings. Don’t use a wire brush as bits of the wire may break off embedding themselves in the surface, which may rust when the water-based paint is applied. Treat any areas affected by mould, lichens, algae and moss with a good fungicidal wash Make good minor defects with an appropriate filler.
- New or sound bare surfaces should be sealed with a thinned first coat of the masonry paint (smooth or textured) to ensure good adhesion of the finishing coat(s). Surfaces that remain powdery, friable or chalky after thorough preparation should be sealed with a coat of stabilising primer but never seal sound, new or bare surfaces with stabilising primer as it will do more harm than good.
- Masonry paints are designed to let the walls breathe so if you apply a glossy sealer that is not required then any moisture vapour passing through the paint film will condense on the glossy sealer causing the masonry paint to blister and flake.
- Painting metal gutters and pipes outside:The inside of metal gutters are best coated with a layer of a suitable bitumen-based paint for protection against damp conditions. The outside, brackets and downpipes can all be painted with either normal undercoat and gloss. Any bare areas of metal must be prepared and primed with metal primer first
- Painting Plastic Gutters and Pipes Outside:Plastic gutters and pipes are normally left unpainted but if they have discoloured then they are best painted by applying 2 coats of gloss paint direct to the cleaned plastic. Primers and undercoats are not required.
- Stripping Wood:There is no need to strip existing paint coatings unless they are in a very bad state. It is always better to continue painting and build up the surface than to start again from bare wood
- If you do have to strip down to bare wood, use a good quality paint stripper