How to Choose the Right Wood for Your Deck – Ease of Working with Tools
If you’re planning on building a wood deck yourself, one of the important considerations is the degree of difficulty in working with the lumber chosen. Not only do you want the lumber to be relatively easy to cut with normal hand or power tools, but you need to consider if splitting may easily occur when nailing, how easy it is to drive nails into the wood, and how easy it is to obtain a smooth finish on the surface of the decking.
The surface finish of course is taken care of by the lumber mill. But even with the best mills, for some exceptionally hard species you may notice machining marks remaining on the surface or a surface roughness due to lifting of the grain whilst machining.
Most durable hardwood species are both dense and hard and should ideally be cut with a carbide tipped saw. For softwood species, a handsaw can be quite OK, but even in this case, a carbide tipped saw makes the job a lot easier and quicker.
With some hardwood species such as Teak and Turpentine, rapid blunting of cutting edges can occur due to the presence of a higher than normal level of silica. Ipe is another species which can cause blunting of cutting edges and care also needs to be taken when working with Ipe due to the fine yellow dust produced when sawing or drilling, as it has been known to cause dermatitis with some workers exposed to the dust.
Splitting when nailing is a common problem and some species are more prone to splitting than others. For many hardwood species, pre-drilling will be virtually essential, although use of a nail gun can overcome this requirement to some extent. Even with some of the more brittle softwoods and in particular cypress species, care needs be taken when nailing. If nailing close to the end of the decking planks, pre-drilling is always recommended to avoid stress in the timber which may cause to cracks to develop at later stage.
If using nails to fix the planks to bearers and the deck is fully exposed to the weather, standard iron nails should not be used as they will rust. Instead you should use galvanized nails or nails specifically designed for exterior use. Another point to note is that some lumber species can corrode iron fixings or fastenings due to the extractives in the wood. Although this will only occur when the deck is situated in exposed weather conditions, it can speed up the corrosion of standard iron nails and cause them to fail quite rapidly. Western Red Cedar is one such species with extractives that can cause corrosion and some other species which are slightly acidic such as Kempas, can also cause corrosion with standard iron nails.
Similar precautions need to be taken against corrosion if using screws rather than nails to fix the planks to the bearers. Stainless steel screws are certainly the best option, but plated screws could be considered provided they are recommended for exterior exposure. Remember that as the head of screw is much larger than a nail, rust stains will be more of a problem and can leave unsightly black marks around the screw holes if inappropriate screws are used.
Alternative fixing devices
A number of alternative fixing materials are also available which have the advantage of leaving the surface free of nail holes or screw holes. These systems generally rely on a fastening device which is driven into the side of the planks and attached to the bearers below. The only obvious drawback of this system is that replacing a single plank if damaged or decayed in any way can only be achieved by nailing or screwing the replacement plank back in place in the conventional manner.