Interior Walls and Ceilings

Surface Characteristics

surface-characterstics-check (1)

  • 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

attention

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 PVA should be used. Contact us for more advice.

Drying time (Mature builds)

  • Moisture is not generally a problem, except where leaks, damage to damp course or any other issues result in mature walls being structurally damp

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 should 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 primer or use Bonding Liquid

Hard wall plasters

  • Gypsum based plasters are 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 Bonding Liquid

 

New Surfaces

newly-plastered-wall[1]

What is it?

  • 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 crack filler

PVA emulsion

  • Priming not necessary
  • See the Sparcolux PVA paint range for choice of paints

Enamels, Flat Alkyd finishes

Solvent painted surfaces

enamel-painted-wall[1]

What is it?

  • Enamel based paint on wall, typically gloss enamel, eggshell enamels

Treatment

  • Clean down and ensure adequately dry
  • If existing paint is in poor condition, remove completely by scraping, scrubbing and sanding off
  • Prime bare areas with Sparcolux Paints Bonding Liquid

 

PVA painted or lime-washed surfaces

pva-painted-wall[1]

What is it?

  • Previously PVA based paint on 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 Sparcolux Paints Bonding Liquid
  • Gently sand entire surface to provide adhesion
  • See the Sparcolux PVA paints range for choice of paints, no primer required
  • For Enamels, first prime surface with Bonding Liquid

 

Wood chip and lining paper

wallpapered-wallWhat is it?

  • Wood or paper based materials typically used in kitchens and cupboards

Treatment