HOUSE PAINT TO SUIT ALL CONDITIONS

Bay of Plenty Beacon, Volume 15, Issue 61, 26 June 1950, Page 7

HOUSE PAINT TO SUIT ALL CONDITIONS

For some time house paints made to* specifications of the New Zealand Standards Institute have been available, and it is possible that when weathering tests throughout the Dominion are completed recommendations will be made for paints suitable for specified areas like the Bay of Plenty. Primarily to find out the effect of climate on the paint of outdoor woodwork, structres some 200 feet long, built in sections of four panels, each of three 6ft. weatherboards, are to be seen in exposed places in the Provinces of Auckland, Wellington, Canterbury, Westland and Otago. The structures are ■a project of the Dominion Laboratory, Department of Scientific and Industrial Research, and every six months, a research chemist from its Paint Section visits these outdoor paint exposure test fences, and inspects each panel. Detailed 'records of weathering effects and failures are recorded under* eight to i.en headings for comparison with the records of previous visits and other areas.

The. location of these test fences was decided only after careful study had been made of the types of weather prevalent in districts throughout New Zealand, and it has been found that most weather conditions normal to this country are experienced at one or other of toese sites. Given a standard paint correctly applied, under similjar conditions and on similar timber, its durability is largely determined by the weather, and whilst one compound will be ideal for one district, it may not be the best for another district.

Only after prolonged tests will the many factors influencing paint failure be put in their proper relation, but a simplified explanation of the effects of two of the main pigments—white lead and zinc oxide—will show her climate affects durability. White lead “chalks” easily, and sunlight accelerates chalking, but the early failure of this class of paint is experienced only when the chalk coat is frequently washed away—it is therefore unsuitable in districts of heavy rainfall.

Tests have already shown that paint mixtures with the two pigments, in varying percentages related to the prevailing weather conditions of the areas, have given paint surfaces of good durability.