EXTERIOR WOOD SEALING REQUIREMENTS
Exterior finish must protect wood from the elements besides making it look good. Protection against deterioration is a high priority.
WATER & MOISTURE RESISTANT
Water and moisture resistance is a high requirement especially at the coast and particularly at the sea shore.
The biggest consideration in our South African climate is the damage done to surface coatings and consequently to the wood by the sun. UV-radiation (Ultra Violet radiation) is the culprit and a sealer must have high UV-absorption factors. Note: The inclusion of tinting in exterior sealers increases the UV-absorption ability.
Despite extravagant claims by some manufacturers transparent exterior coatings last about 18 months before they need refurbishing. This depends on the severity and exposure to the elements.
Because outdoor applications do deteriorate, ease of general maintenance and re-coating is a major consideration.