NVD Hardwood
The natural durability of timber is classified in five broad categories based on their performance in ground contact. Timbers in the Naturally Very Durable Hardwood category have a life expectancy, without preservative treatment, of more than 100 years in UK ground contact for section sizes of 200mm upwards. These timbers are usually very hard, extremely strong and have good fire and chemical resistance.
Dense Very Durable Hardwood in large sections seasons slowly over a number of years. During the acclimatisation process cracks/checks may appear, especially during periods of hot
dry weather. These are more noticeable early in the seasoning cycle, than after in-depth equalisation of moisture content has taken place.
The above characteristics of solid timber may cause a certain amount of concern until it is understood that they do not generally compromise the strength or durability of manufactured components. Unlike preservative treated softwoods, the durability of NVD Hardwood is throughout the full section and any moisture ingress would not normally result in internal decay.
All hardwoods exude tannin as part of the natural weathering process, when certain tannins (particularly Oak) come into contact with ferrous particles they can react and create a blue/black ink type stain. This is perfectly normal and can be removed with standard household detergents/bleach. For more stubborn stains an Oxalic Acid based product can be used.
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