INTERIOR WALLS

SURFACE CHARACTERISTICS

  • Covers interior walls and ceilings and includes materials such as plaster, cement, concrete brickwork, wood chip and lining papers and similar materials
  • As large amounts of water are used in the building of internal walls and ceilings, the risk of moisture interfering with the paint drying process is high and needs to be managed.
  • Highly impervious paints like enamels are especially at risk of damage from moisture

WHAT TO LOOK OUT FOR:

Drying time (New builds)

  • Can take weeks, even months.
  • As a rule of thumb, for every 5mm of thickness, allow 1 week of drying time.
  • Where painting cannot be delayed, a relatively permeable primer such as water based plaster primer should be used.

Drying time (Mature builds)

  • Leaks, damage to damp course or any other issues result in mature walls being structurally damp, which result in major paint problems and even pose a health risk to the inhabitants.

Alkalinity

  • Results in Saponification of oil-based paints, which needs to be avoided at all costs.

     

  • Alkalinity of PVA emulsion paints results in discolouration and efflorescence.

     

  • Both conditions need to be avoided.

Unsound Coatings

  • Older buildings painted with water-paint or lime-wash will almost certainly be flaky or powdery in appearance.
  • Thorough preparation involving the removal, as far as possible, of all surface contaminants and unsound paints is required.
  • Apply an alkali resistant plaster primer or use penetrating sealer such as Sparcolux Paints KeyBond.

Hard wall plasters

  • Gypsum based plasters are a favourite for interior surface preparation for their quick drying abilities.
  • Due to surface smoothness (from trowelling) and invariable fine dust film, best practice is to apply a KeyBond.

SURFACES:

New Surfaces

Exterior surfaces not previously coated

Treatment

  • Ensure surface is clean and adequately dry (using time guide above).
  • 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.