Over the last 30 years, timber decking has firmly established itself as a quick and aesthetic option for external landscaping. With a meteoric rise thanks to the TV makeover programmes in the 1980s and then the introduction of alternative materials in the last 10 years, the traditional timber deck has recently had to look at its shortcomings and adapt to market demands for safety, performance and quality.As a material, timber with its sustainability, natural durability and timeless looks, remains a natural choice for architects today, and many are now coming back to specify timber for its simplicity, ease of installation and enhanced safety.
The biggest barrier that timber has had to overcome is its propensity to become very slippery, very quickly in the UK climate. And for commercial designers, the need for safety and peace of mind over the lifetime of the project is paramount. Timber is an attractive substrate for algae to quickly take hold – the timber surface retains moisture and therefore the can remain damp long after the rain has gone. Repeat this cycle many times over the season and you have perfect growth conditions for algae. Of course this algae growth can be physically removed, but particularly on commercial sites, this incurs additional time, costs and even logistical difficulties.
The solution lies in specifying a non-slip timber decking board. These boards use an unobtrusive aggregate treatment to give a long lasting slip resistance finish. And they can be independently assessed to a slip resistance test BS7976, providing an objective measure to help rate the boards. This test is available as an initial measure of the new board, but also now as a measure after 10 years – an “extended performance guarantee” of how well the anti slip properties of the board will last.
Great developments have been made in the treatment of timber since those early days of arsenic based chemicals. And by using the latest micronised copper technology softwood timbers can be treated for up to 30 years ‘in-service-life'. By using the Use Class Tables as defined in British Standard BS EN 335, there are 5 “use classes” to which timber can be treated. For timber decking it depends on the application i.e. where it is being used as to what will determine the level of performance expected from it. For example, if the timber is in direct contact with either the ground or freshwater it should be treated to Use Class 4, but where the timber is above the ground Use Class 3 applies.
Make sure the timber for your deck is treated to the appropriate Use Class, not just for the deck boards but for every element of the structure.
Quality of Timber
When looking to specify timber decking, the application should determine the most suitable species, grade and finish that is chosen.
Softwood timber is extremely popular, versatile, and readily available from many sources. Scandinavian timber is great value for money, and provides a good balance between quality of slow grown timber stock versus cost. It comes in several grades, but the most frequently specified ones are Fifths and Unsorted.
Hardwoods are another option to consider, particularly for marine/freshwater applications, and with many hardwoods having an expected in service life of 40 years plus, the higher initial cost can be a good investment when taken across its whole lifetime. And many hardwoods will now come with a fully certified “chain of custody” to ensure they are a safe environmental choice.
Which brings us to the use of timber for decking compared to other materials. By specifying either FSC or PEFC certified timber, you can be sure the decking has come from a sustainable forest and will be environmentally sound. Being a natural grown material, the harvesting, production and treatment of timber also provides sustainable employment, so by choosing timber over other “plastic” based materials goes beyond just the product – you help sustain the whole supply chain.
Timber decking is a naturally grown material that is wholly sustainable, and given the current range of finishes, species available and its performance characteristics, it is a material that is more than fit for purpose for buildings of the future. Its versatile, safe and extremely durable. Throw away any prejudices about slippery timber decking and specify a product that is timelessly beautiful, renewable and measurably safe!