Water stains and mould can ruin the appearance of exterior surfaces, causing unsightly black stains on exterior walls and bleed-through on fresh paint. This guide shows you the best way to paint over exterior water stains, blocking marks effectively and preventing mould from reappearing for a flawless, durable finish.
All surfaces must be clean, dry and free from anything that will interfere with the adhesion of the materials to be applied. Remove loose and failing material by scraping or brushing with a stiff bristle brush to a sound edge. Feather sound edges with a fine grade abrasive paper.
Prior to painting, the moisture content should not exceed 18%. Remove all dust. Remove all visible signs of organic growth and treat the areas with Zinsser Mould Killer in accordance with the manufacturer’s instructions. Allow to dry.
Wash with hot water and liquid detergent solution to remove any contaminants, frequently changing the water. Rinse thoroughly with clean water to remove all residues. Allow to dry. Fill any cracks and small surface defects with a suitable filler in accordance with the manufacturer’s instructions. Allow to dry. Rub down with a fine grade abrasive paper.
Remove all dust. Patch prime all bare and filled areas with one coat of Cover Stain® Primer Sealer in accordance with the manufacturer’s instructions. Allow a minimum drying time of 2 hours in normal drying conditions. Bring forward patch primed areas with one coat of Cover Stain® Primer Sealer. Allow to dry.
Prime all water stained areas with one full coat of [Cover Stain®](Prime all water stained areas with one full coat of Cover Stain® Primer Sealer. Allow a minimum drying time of 2 hours in normal drying conditions.) Primer Sealer. Allow a minimum drying time of 2 hours in normal drying conditions.
Decorate with two full coats of AllCoat® Exterior Satin or Gloss in accordance with the manufacturer’s instructions. Allow a minimum drying time of one hour between coats.
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Computershare Governance Services
The Pavilions
Bridgwater Road
Bristol
BS13 8FD
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Tor Coatings Ltd
21 White Rose Way
Follingsby Park
Gateshead
Tyne & Wear
NE10 8YX