The importance of correct deck building is not always fully appreciated. Peter Bissett of Cottage Concepts, Timber Deck Member of the Institute for Timber Construction South Africa (ITC-SA), says that it is not uncommon for clients to be told that they don’t need plans or an engineered design for their timber deck.

“This is simply not true and the general rule is that if anyone can be injured because of a structural failure, like a decking slat breaking, for example, then an engineer should be engaged to check the contractor’s design. Anyone interested in having a deck built must be aware that if they do so without plans, when the time comes to sell their property, they may well end up having to submit plans, as most councils now require that plans are up to date prior to the release of rates clearance certificates,” says Peter.

Legislation governing timber deck construction
Timber structures must be designed and built in accordance with the South African National Standards (SANS) 10163, which governs the structural use of timber and SANS 10082 “Timber Frame Buildings”. An engineer would make use of SANS 10163 on a timber decking project.

SANS 10082 is the code of practice for timber structures and your decking contractor should have a copy of this document as well as SANS 10043 (Solid Wood Decking) on hand. The National Building Regulations must also be strictly adhered to when constructing a deck – or any other structure for that matter – and will refer the designer, builder and engineer to the relevant code or regulation for correct execution of the project.

Deck maintenance
A number of factors will influence the required maintenance of a deck, including location, extent of exposure to the elements, type of timber and the type of coating used. A deck should not be left for longer than 18 months before receiving routine maintenance; a 12-month maintenance cycle is preferable. If the deck isn’t in a bad condition, then it shouldn’t be sanded down with an industrial floor sander as this reduces the number of times the deck can be sanded.

Do not accept a deck if…
There are a number of individuals in the market who are not qualified or experienced in the field of timber decking. Do not accept a deck if:
• The deck bounces when walked over.
• Balustrade posts are nailed instead of bolted to the sub-structure, as they will eventually come lose.
• The balustrade has any gaps through which a 100mm diameter ball can fit.
• There is any part of the deck that is higher than 1m off the ground that doesn’t have a balustrade.
• There is not at least 450mm of space below the decking for air to flow around the timber.

For more information, contact The Institute for Timber Construction South Africa on Tel: +27 (11) 947 1961 or via www.itc-sa.org.