Timber iQ October - November 2019 // Issue:46 | Page 45

FEATURES FIND THE BEST TREATMENT OPTION • Hardwoods and softwoods often require different treatments. A reputable surface-treatment supplier should be able to advise you in this regard. • Keep to the supplier-recommended maintenance schedule. This will ensure a longer-lasting, good- looking product that will ultimately be less costly to maintain. • Naturally durable hardwoods should be used for applications where the recommended maintenance schedules cannot be met. • For higher-exposure classes, such as protection against insects and in-ground or water applications, additional impregnation treatments are required. • Timber is a natural product and therefore cannot be used in all applications. either within a certain timeframe (for example, within 24 months), or when the surface appears dry. Penetrating treatments such as oil-based products are similar, but with one key difference: they are far more forgiving when not timeously maintained, and a fresh coat can usually be applied without the need for any remedial action. In such cases, though, the wood’s appearance might have changed, depending on how long the surface remained unmaintained. Certain treatments were shown to provide very good alternatives to regular oil or varnish products, with regard to both penetration and maintenance requirements. Significant advancements were demonstrated with penetrating sealers and water-based treatments. A very high-density tropical hardwood showing the importance of matching surface treatments to the species being treated. FILM-FORMING VS NON-FILM-FORMING In addition to the maintenance requirements of different surface treatments, users should be aware of the differing effects of film-forming and non-forming treatments on wood. A film-forming treatment can prevent moisture from penetrating the timber and therefore help maintain its original aesthetic appearance for as long as it is regularly maintained. If the wood is not maintained, however, or surface wear causes flaking, its appearance can very quickly deteriorate. Penetrating treatments may allow in some moisture, but, because the wood is already penetrated by oils or waxes, the effect on the wood’s properties is minimal. The surface might discolour over time, but the structural condition of the wood remains intact. FACTORS TO CONSIDER WHEN CHOOSING A TREATMENT Ease of application should be considered when considering surface treatments, as some products are not easy to apply with a brush or roller. The initial treatment cost, in addition to maintenance costs, should also be considered. In some test cases, the more expensive treatments did not perform better in the long run. The aesthetic appeal of a treatment should also be considered. Gloss and matte-type finishes are available for most product options and generally have similar protective properties, but a glossy surface might not stay glossy in certain applications. www.timberiq.co.za Merensky walkway after 18 months’ exposure and a fresh maintenance coat. // OCTOBER / NOVEMBER 2019 43