From designing an outdoor play or dining area to a nature reserve or urban development, carefully planned landscaping – including decking – has a role to play. Laura Qualters from Marley discusses
Decking continues to be a popular way of adding an extra dimension to outdoor areas, from creating additional living spaces in the garden, through to boardwalk-style exteriors, or extra dining space at hospitality and leisure establishments.
Decking provides context for the building; not only affecting how it sits on the site and in the wider landscape, but also shaping visitors’ impressions as they approach – especially for the first time.
And, for those keen to select materials which deliver increased environmental credentials, timber decking has the lowest embodied energy when compared to other hard landscaping materials. When sourced sustainably with full FSC & PEFC accreditation, it can effortlessly combine style and substance.
Grooved vs smooth
Part of providing a pleasant experience for users of all abilities is ensuring the decking specified provides a consistent, level surface to move across, which might otherwise create a hazard and can make the experience uncomfortable.
When thinking about decking, many people picture the traditional grooved appearance, but smooth profiles are becoming increasingly popular. A smooth board offers a different feel and appearance to the deck when compared to the traditional look of a grooved board but also has many other benefits.
A smooth board with less abrasive grit can give a more comfortable surface for urban footwear, wheelchair users and pushchairs while still exceeding the slip resistance requirements of the Health and Safety guidelines.
Anti-slip
Traditional decking boards with a high level of grip can exacerbate trip hazards, especially at the boundary with a different surface where there’s a transition in grip level. For the less able, that high level of grip continues to cause a problem across the deck.
Slip resistance in commercial decking is best achieved by using factory applied anti-slip strips. A board can feature two or three strips depending on the level of resistance required, three being suited to high-risk areas. Using a less abrasive grit for the inserts reduces any trip hazard while still achieving good levels of slip resistance.
As a further aid to accessibility and inclusivity, specifying anti-slip inserts in bright or contrasting colours helps to highlight changes in level or direction.
Decking is independently tested to confirm its slip resistance. The Health and Safety Executive’s (HSE) preferred method is the pendulum test – described in BS 7976, parts 1 to 3 – which replicates the action of somebody’s heel striking the surface and measures the dynamic coefficient of friction.
Regulations
One of the first points of reference when planning outdoors spaces and circulation routes is the guidance in national Building Regulations relating to access. Provisions apply whether the design relates to a new building or extending/altering an existing building.
Following the guidance in Approved Document M for England and Wales helps to achieve compliance with Building Regulations. Section 4 of the Building Standards technical handbook in Scotland, and Technical Booklet R in Northern Ireland, also deal with access considerations.
Compliance with Building Regulations does not necessarily require strict adherence to the guidance contained in these documents. Alternative solutions are permissible, and the more complex the project, the more consultation with the local authority is recommended.
BS 8300 is the code of practice for designing accessible and inclusive buildings and Approved Document M is based on the guidance in this standard, though there are some differences.
The Equality Act 2010 should also be considered when designing and specifying outdoor spaces and areas of decking. The Act is broader in scope than national Building Regulations, so meeting regulatory requirements does not automatically mean compliance with the Equality Act.
Safety is another element of Building Regulations. Approved Document K in England details guidance for stairs and ramps; the requirement only applies to external stairs and ramps at a building’s entrance. If not at an entrance, then only the requirements for access apply.
For other UK countries, guidance on safety can be found in Approved Document K in Wales, Section 4 in Scotland, and Technical Booklet H in Northern Ireland.
Low maintenance
When looking to specify a decking solution, many people are surprised to hear that timber decking is a low maintenance option. Modern timber decking boards, with the right preservative treatment from the outset, require very little maintenance.
Aside from a brush with a broom and an annual clean with a deck cleaning product to remove any grease or discolouration, they can be left to weather naturally with no need to re-treat.
The most important thing is to make sure products are pressure treated correctly in the first instance to get the best out of them through their lifespan. Default anticipated service life is usually around 15 years, but some specialist suppliers will treat to achieve a 30 year desired service life.
By choosing the right product through applying these considerations, architects can specify the ideal decking to achieve a stylish, safe and low risk space to transform a landscape.
Laura Qualters is national technical manager for Marley