This was a wooden deck built in balau for a client who had opened a Bed and Breakfast on the coast. As you can see form the pics the wooden deck was built in the front of the property overlooking the sea. There were of course strict time lines in which we had to complete this wooden deck as they had already made confirmed bookings. With these job which are a fair distance from home we normally rent accommodation and pay the builders a live out allowance for food etc. It inevitably pushes the cost of the build up slightly which is unavoidable.
There are some before and after pics in this article. We had to excavate the soil below. It is always best to leave a fair amount of space below the bottom of the structure and the bottom of the deck boards to allow sufficient airflow for water evaporation. If the deck structure is touching the ground then one would need to use H4 CCA Treated timber which has a minimum life span of 20 years in constant contact with wet soil as per SAWPA (South African Wood Preservers Association). H3 CCA Treated pine as a structure which is NOT in constant contact with wet soil has a minimum life span of 50 years if correctly installed. So it makes sense to keep the structure to H3 for cost purposes, and expected minimum life span, but keep it well clear of any soil. By allowing air to flow freely between the structure and the ground keeps everything relatively dry below and the deck structure will last a lot longer. Continual dampness below speeds up rot and premature failure. In this instance we excavated to at least 300mm below the structure.
There was a pool that had been installed prior to our build by Clear Blue Pools – Gary Botha (071 679 1013) and we worked closely with the pool builder so that the concrete ring beam of the pool was set down 60mm from the desired deck height (top of deck). This allows us a 40mm batten on top of the concrete ring beam and a 19mm deck board. 40mm is the minimum we like to allow for this purpose, again to allow for sufficient air flow to keep things dry between the deck surface and the ring beam. These cleats or battens are fixed directly to the concrete ring beam and the rest of the joists which are suspended above soil become a 38 x 114 to give it lateral strength.
The rest of the deck was pretty much the same then as the other decks we’ve built using 19 x 68mm yellow balau deck boards, counter sunk screw holes filled with clear epoxy and saw dust mixture, sanded flat and oiled using a decking oil.
For a free no obligation quote on your deck please call us on 082 496 5444 or use the contact us form below.
Here’s a straight forward wooden balau deck we built in Kloof, Durban in October 2018. There were a few angles that had to be cut precisely to finish it neatly but other than that the deck was straight forward to build.
We used an H3 and H4 CCA Treated pine substructure. Because the pine is S5 (Industrial SABS approved grade) it is strong enough to be used as a structure for various building purposes. It is also relatively inexpensive in comparison to other hardwoods that could be used as decking structure. Being S5 it contains a certain amount of knots per square metre and is therefore SABS approved as structural timber. Timber with more knots per square metre is normally used as knotty pine ceiling boards where there is very little structural pressures on the timber. Timber with less knots per square metre is referred to as semi clears or S7 grade. S7 becomes quite expensive and is used as deck boards at times to eliminate knots failing on the deck surface. However because one would need to use twice as much wood (38mm thick) when using pine deck boards, the cost is the same as using a 19mm x 68mm balau deck board at half the quantity of wood. As such we use 19 x 68mm yellow balau deck boards as the surface for most of our wooden decks in Durban. The balau is far more stable being twice as dense and hard with a regular straight grain and as such these balau deck boards don’t twist, cup or bow as easily as pine. With the pine being H3 CCA treated it has a life span of at least 50 years outdoors in the rain and weather.
We added a small flight of open riser steps to this deck to gain access to the garden. These are done in full solid balau using 30mm stock. Normally the stringers are 30 x 215 and the treads are made of multiple pieces of 30 x 102 with cleats fixed to the stringers and the treads are fixed to the cleats. They don’t work that well in pine as the pine becomes very visible throughout and one ends up cladding it anyway which brings the cost back to the same as solid balau. The alternative to open risers steps is to do closed risers where box type steps are made of pine structure and then clad resulting in the riser being closed.
The screw holes of all our decks are counter sunk with a Kalgard decking screw and filled with a clear epoxy and saw dust mixture to match the colour of the wood and then ground flat and sanded smooth prior to oiling the deck. You’ll find other articles on this site where we discuss the pros and cons of using oil vs other finishes available on the market and leaving the deck to naturally grey and weather. If you use the search bar at the bottom right and search for maintenance you’ll find a complete article on deck maintenance.
For a free no obligation quote on your wooden deck in Durban and surrounding areas, please use the contact us form below or you can call us on 082 496 5444.