Preparation is key
- When decorating exteriors it is important to plan the project to ensure that you achieve the best results.
- It is important to understand that paint will only perform well with the correct surface preparation.
- Using the correct preparation products and application tools can make the job easier and result in a longer lasting, more aesthetic finish.
- Understand why do we paint exterior masonry. Two key motivations are protection and decoration.
- Protection is achieved by the paint creating a barrier against not only moisture and wind but also the adverse effects of UV rays from the sun that damage exterior surfaces.
- Old flaking or blistering paint
- Worn or damaged surfaces
- Damp and fungal growth
- Unstable chalky surfaces
- Consider access to out of reach areas and the need for ladders or towers
- What protection is required e.g. dustsheets, masking tape etc
- It is important to choose a suitable day as exterior painting in especially cold weather (below 8°c) or extremely hot weather creates its own challenges with paint not drying or indeed drying too quickly.
When removing old flaking masonry paint, use a scraper where possible then for small flakes a stiff bristle brush will remove residual flakes. It is important NOT to use a wire brush on the masonry surfaces as metal particles can become embedded on the surface, these react to the water based masonry paint thus resulting in potential rust spots that will make the walls look unsightly. When removing old paint it is recommended that you wear safety goggles / glasses, gloves and a mask, this will reduce the risk of damaging your eyes or breathing in dust particles.
Apply the fungicide solution to the affected area plus an overlap to ensure the solution penetrates the surface and kills the organic growth. Again check the manufacturers pack instructions as to the recommended time prior to painting over the fungicide solution, this is usually 24 hours. This will ensure a clean surface for a better adhesion of the masonry paint.
Mould tends to grow in damp conditions so it is important to deal with not just the mould problem but also the cause of the problem as this could be a leaking gutter concentrating water on the wall creating a damp area.
To check for this issue wipe your hand on the surface to be painted and if you have dusty particles on your hand then you will require to use a stabilising solution. The stabilising solution is very easy to apply using a 3” brush direct to the surface, allow to dry for 24 hours prior to painting. The stabilising solution seals, and stabilises to allow for good adhesion of the masonry paint, it also allows the paint to cover further.