PREPARING AND PAINTING EXTERIOR WALLS

SURFACE CHARACTERISTICS

  • Many building materials (brick, sand, cement) used in building walls are alkaline.
  • With moisture, this alkalinity can attack the paint coating.
  • Sufficient drying time is required especially when using good quality paints.
  • Special attention to new walls or old walls with leaks, faulty damp course or structural defects must be paid to, to ensure that ample drying time is given before applying paint.

WHAT TO LOOK OUT FOR:

Efflorescence and Fungal growth

Click here for more information about these conditions. Disruption to the PVA drying or paint discolouration poses a risk and the treatment under the problems section is advised

Chalky Surfaces

Surfaces with existing coatings that are crumbling or powdery

Treatment

  • Very thorough surface preparation to ensure that the paint has a solid base to adhere to is required.
  • Preparation includes: chipping, scraping and brushing of all loose contaminants. If insufficient, consider blast cleaning.
  • Application of a penetrating sealer such as Sparcolux KeyBond

See the the Sparcolux range of Wall & Ceiling paints for our choice of top coat paints

New Surfaces

Exterior surfaces not previously coated

Treatment

  • Ensure surface is clean and adequately dry
  • Minor cracks that won’t be bridged by the paint, need to be filled with cement mix or and exterior crack filler
  • Prime with with either Water based Plaster primer or Solvent Based Plaster Primer paying special attention to instructions provided with these products.

     

Apply one of our Sparcolux range of Wall & Ceiling paints for our choice of paints

Enamel Painted Surfaces

Enamel based paint on wall, typically gloss enamel or eggshell enamel paint products

Treatment

  • If existing paint is in poor condition, remove completely by scraping, scrubbing and sanding off.
  • Fill cracks with exterior crack filler.
  • Prime bare areas with a penetrating sealer such as Sparcolux Paints KeyBond.
  • NB: Gently sand entire surface with 100-120# Sandpaper to key the surface for good topcoat adhesion.
  • Clean down surface and ensure adequately dry.

Apply a top coat from one of our Sparcolux range of Wall & Ceiling paints.

PVA painted or lime-washed surfaces

Water based Wall & Ceiling paint previously applied on the wall.

Treatment

  • Clean down and ensure adequately dry.
  • If existing paint is in poor condition, remove completely by scraping, scrubbing and sanding off.
  • Fill cracks with exterior crack filler.
  • Prime bare areas with a penetrating sealer such as Sparcolux Paints KeyBond.
  • Clean down and ensure adequately dry.

See the Sparcolux PVA paint range for choice of paints.