For exterior surfaces it is very important to undertake repairs of any wall imperfections before commencing painting. The most common problem with exterior walls, especially old constructions, is cracks in the wall. Avoid applying putty or filling compound while painting exterior surfaces. Fill up cracks with a 1:3 cement and sand mixture. All external drainage pipes must be checked for rusting or leakage. Any faulty plumbing must be rectified.
Special attention must be given to the roof. Check for cracks near the edges and close to the water reservoirs. Proper masonry or waterproofing work on the ceiling will enhance the performance of the painted surfaces.
- Newly plastered surfaces must be allowed to cure for at least 35 to 45 days before painting.
- To ensure long protection, the surface to be painted should be free from dust, grease and any loose materials.
- Remove any fungus and algae growth thoroughly by brushing it vigorously with wire brush and then cleaning it with bleaching powder solution in water (dissolve 10% bleaching powder in 1 litre of water, filter the solution and apply with a brush or sponge). This treatment should be done with greater care on the top of the awnings, sunshades, parapets and other horizontal surfaces where water is likely to accumulate during monsoon.
- Previously oil painted surfaces should be sanded thoroughly to remove loose particles and made dull and matte for better adhesion. Exterior rough surfaces, previously coated with cement paint, should be wire brushed and washed with water thoroughly and dried completely. Before painting, ensure that the surface is free from chalking.
- The exterior surface should not be affected by water and constant dampness should be avoided. If you are painting during the rains, allow for 2-3 days of total sunshine for the surface to dry out completely and before commencing painting.
- Apply a liberal coat of Asian Paints Exterior Wall Primer using recommended method.
- Apply two coats of top coat paint at recommended dilution. You can use Apex Weatherproof Exterior Emulsion or Apex Textured Exterior Emulsion or Ace Exterior Emulsion as top coat.
- A gap of 4 to 6 hours must be given between two coats.
- It is recommended that horizontal surfaces like the tops of awnings and parapets must be given an additional coat for greater protection.
Surface should be free from dirt, dust, grease, rust, moisture etc. The area which is not to be painted must be covered by a masking tape, paper and/or cloth.
- De-grease and de-rust ferrous metal substrates by suitable treatment.
- For nonferrous metal substrates like aluminium as well as galvanised iron, tin, etc, pre-treat the surface with Apconyl Wash Primer - WP 636. For ferrous metal substrates, apply AP Metal Primer - Corrosion Resistant either by brushing or spraying.
- If necessary, the use of AP Knifing Paste Filler is recommended to fill up dents and rectify surface imperfections.
- Ensure that the surface is free from moisture and loose matter.
- Apply one more coat of AP Metal Primer- Corrosion Resistant by brushing or spraying to cover puttied areas.
- For best results, allow the primer coat to dry for 6 hours and dry sand with emery paper no. 320 before application of subsequent coat.
For best results
- Allow the surface to dry overnight after application of primer as above.
- Apply top coat (Apcolite Premium Gloss Enamel or Apcolite Premium Satin Enamel, Gattu Synthetic Enamel) using the recommended thinner. For best results, apply two coats allowing 8 hours of drying time between two coats.
- The first coat should be wet sanded with waterproof emery paper grade 400 before applying the second coat.