author:Malcolm D Kay
To ensure that your deck has a long, trouble free life, it’s important to use the right fixings used to fix the planks to the bearers. This choice can be influenced not only by the prevailing climatic conditions, the proximity to marine environments, but also the actual wood used. As your deck will around for a long time, it?s best not to compromise too much on the fixings as the higher cost of better quality products will be repaid many times over with a longer service life and better looking deck.
Normally, standard iron nails should not be used on external decking as they can rapidly corrode in certain climatic conditions or close to marine environments and not only leave black stains around the nail holes, but can eventually corrode so extensively that they will simply snap. Remember that all wood will twist and warp to some extent so its important that wood planks are firmly fixed to the bearers at regular spaced intervals to keep the timber from moving. If you wish to use nails, then you should use a good quality galvanized nail, recommended for exterior decking. Note that some species of lumber – in particular, Western Red Cedar, Merbau and Redwood – contain tannins that can cause corrosion to occur more rapidly than with other species of lumber.
If using screws to fasten the decking planks to the bearers, then again you shouldn?t use standard steel screws, but either stainless steel or good quality plated screws. But there are many different methods of plating screws and some of the cheaper products may look great in the packet when they?re purchased but not so pretty after a few years of use. Plating may be only superficial at best and in the process of fixing screws into the plank, the plating can be damaged which allows corrosion to start from day 1. So it’s important that you use a good quality plated screw and is specifically recommended for use on exposed decking.
For the best long term results, stainless steel screws will always be the best option. Although these screws can be significantly more expensive, the extra cost will be repaid in their long life, their ongoing appearance and lack of blackening around screw holes. Note also that in marine environments, stainless steel screws should always be used, as even plated screws can be subject to significant corrosion problems in such harsh environments.
Apart from nails or screws, other fixing devices are also available on the market. These devices generally rely on the metal fixture (typically galvanized iron) being driven into the sides of the planks rather than the top, and the fixing itself is nailed to the bearers. One of the obvious advantages of this fixing method is that there are no screws or nails visible on the top surface. However, one of the disadvantages of this particular fixing system is that if you need to replace planks at any time, it?s very difficult to both lift up and replace any plank in the middle of a deck. Normally the replaced plank would need tobe fixed in a conventional manner with nails or screws. Fortunately such replacements are rarely needed so, this may not be such an important issue.
It’s also possible to cover a deck with a timber surface that does not require any nails, screws or any other fixing devices. Modular wood decking tiles are available on the market which simply lock together by means of an integral plastic base. The base not only allows any water to drain away freely from underneath, the tiles but keeps each tile, securely locked together. Whilst such decks cannot be installed over traditional timber bearers, they can be very useful for covering old concrete patios and courtyards to avoid the trouble and expense of ripping up the lot and rebuilding.