Wooden Balau Stairs built in Blythdale Beach

Wooden Balau Stairs Durban

 

Towards the close of 2017 we built these wooden balau stairs in Blythdale Beach, KZN. The original treads had been made of 19 x 68mm balau deck boards. Because the spacing between the stringers was 1m the stairs were very springy and were bouncing. The general rule is that a 19mm thick piece of balau can be spanned a maximum of 500mm before it needs to be supported by a bearer of sorts. In the case of open riser stairs this is often not possible because one would need a third stringer that would need to be notched to accommodate the tread. As such when we build stairs using balau that are normally 1m wide we increase the thickness of the balau to 30mm which stops any bounce. 40mm can also be used but is really just a waste of wood and therefore money.

The original balau stair treads were installed in 1997. The way the treads had been made up was to attach a cleat to the underside of each tread at the ends. The cleat was screwed from below to the treads (deck boards) and then the whole tread in its complete form was fixed to the steel cleats which were welded to the steel stringers. A bolt had been used to secure them from the top through all the timber and steel with a nut below. Water had therefore been able to penetrate the balau from the top where the bolt hole had been drilled and this, over a 20 year period of time had caused the balau to rot at the bolt hole. Then rest of the treads were in perfect condition with no rot whatsoever, 20 years down the line. Not all balau behaves that way. The balau that was used was obviously of very good quality. Nowadays the quality varies a bit more but balau still remains the most cost-effective hardwood for outdoor applications, be it decking, pergolas or screens.

To avoid the same fate of rotting at the bolt hole we fixed the entire tread in its made up form from below with a stainless steel coach screw instead of a nut and bolt all the way through the timber. As such the only way water can penetrate the timber now is from below which is highly unlikely. Water can still get trapped between the timber cleat and the timber treads but with no end grain to penetrate it should give us more than 20 years of life. 99% of water ingress is absorbed through the end grain of wood and not the face grain. By drilling holes, especially from the top, one exposes a section of end grain and water sits in the hole and gets absorbed. As a precautionary measure when we build sun decks and have to drill from the top to fix our board to the bearer we fill the screw hole with epoxy to keep the water out. There are other hidden fixing methods but I am yet to find one that works the way it was intended to. Deck boards screwed from the top through the face and filled with epoxy remains the strongest and long lasting method. But it is vital to check the epoxy plugs at maintenance intervals and replace if necessary. In the case of these stairs drilling from below into a 30mm piece of balau was ample fixing strength and reduces water ingress.

These balau stair treads we pre -oiled before installation which made it quicker and easier to get them installed.

For a free no obligation quote on timber decking, stairs, pergolas, balustrade and any other outdoor timber project, please contact us on 031- 762 1795 or use the contact us form below.

Wooden Yellow Balau Deck – Kloof, Durban KZN

Here’s another wooden deck we built in Kloof, Durban which is similar to one we built in Hawaan Forest estate a few years ago. It has a fire pit with a U Shaped bench which double up as steps around it. These steps were designed so that they were wide enough to sit around the fire and with a riser that is not too steep to climb.

The substructure or frame was the normal H3 and H4 CCA Treated S5 pine we use. All our decks are built with an S5, H3 and H4 treated pine substructure. S5 refers to the grade of pine which is commonly called industrial grade. It is graded as such based on the number of knots per square metre. S5 is SABS industrial grade and has been passed by SABS to be used in construction. It doesn’t however make a very good deck board as there are too many knots which are not only unsightly but also they can become dislodged leaving a hole in the deck board. H3 and H4 CCA Treated refers to the hazard classification of the treatment as set out by The Wood Preservers Association of South Africa. Each H classification has a specific application and provided the correct H classified timber is used, the life span of the timber can be many more than 50 years.

The deck boards that went on top of the substructure were 19 x 68mm yellow balau deck boards. The other option for deck boards is 19 x 90mm yellow balau deck boards but they do carry a surcharge as they cost more per square metre than the 68mm wide boards.

There are two types of balau readily available in South Africa. Yellow balau and red balau. Yellow balau is more common and is superior to red balau. What we are seeing in South Africa nowadays which is called red balau is a lot more porous and softer and as such will absorb more water and rot more quickly. We only stock and use yellow balau.

This project in Kloof also included a pergola. What we have found to be most cost effective in pergolas is to use a 90 x 90 square balau post, 30 x 215 balau beam and 30 x 102 balau purlins or trusses at about 600 centres. This spec gives the pergola enough timber to be attractive and serve its purpose whilst still keeping costs down. With this particular job we also installed extra battens on top of the purlins. We used 30 x 40 balau for this purpose which again keeps costs down whilst still providing enough timber to keep it looking good and to do it’s job. Other options for battens on pergolas are to use a 30mm wide strip of balau with a 30mm or 60mm gap between. This provides more shade but of course comes with a higher price tag because more timber is being used.

The timber was sanded and sealed with an oil based sealer we use which doesn’t dry on the surface of the wood so it cannot peel and flake. Unlike other coatings which dry on the surface. These tend to peel and flake.

For a free no obligation quote on your wooden deck, pergola, balustrade and stairs requirements please contact us on 031 – 762 1795 or use the contact us form below.

Wooden deck in Massaranduba, Hillcrest, Durban

This deck was built with Massaranduba. Although Massaranduba is about 30% more per square metre than balau the client insisted on it as it is a much harder and denser wood than balau. As such it will last longer. It has a slight reddish tinge to it. This deck is to be left unsealed so will eventually turn grey / sliver. Therefore one will not notice that is massaranduba, but it will last longer. When choosing between balau or massaranduba one needs to weigh up the difference in cost vs. the longevity of both timbers. There is nothing wrong with balau, it will also give you a long life span. Massa is of a better quality and will therefore outlast balau.

We decked around the pool flush with the tiling on the patio which resulted in a single 90mm deck board being used as a fascia on the inside of the pool. Hence the difference in height between the water level and the deck is not that great. Often the deck can come up too high resulting in a big step up to the deck from water level. The pool therefore needs to be set at the correct height, in relation to the patio, to accommodate the deck at the correct height.

A quick note on new pool decks. The hardwood typically used in decking contains tannins which leach out when it rains. Storing them on a tiled surface almost always results in stains being left on the tiles after a downpour. Likewise one needs to be careful of installing the fascia on the inside of the pool, or deck boards that are installed on the pool’s edge, prior to filling the pool with water. If there is no water in the pool and it rains, these tannins will leach out and run down the new marbelite pool surface, staining it. The only way to get rid of the stains successfully is to sand it off. It is advisable therefore to get the pool done and filled before decking up to the sides of the pool and installing the fascia board. Alternatively, don’t marbelite until these tannins have completely leached out. It’s a tricky one because the pool contractor doesn’t want to marbelite until the lawn is done because of dust. The landscaper normally comes last, so it’s a bit of juggling that is required.

We decked around a circular concrete slab which is to be a fire pit and up to the edge of the brick and plaster bench around the fire pit.

We also installed a small pergola above the sliding door and included a small bar counter that can be accessed from both sides of the patio and deck. There was also a small decked area at the back of the house next to the fish pond and a screen on the front of the house.

For the screen we used a 20 x 30 slat instead of a normal 19 x 68 deck board. Although a 19 x 68 deck board works well as a screen, a narrower piece (30mm) with a smaller gap is a bit different and not the run of the mill timber screening. Although it is slightly more expensive than a normal 68mm wide deck board screen, it is very effective.

All in all a very nice job to work on and a pleasure to work with Massaranduba. It is lovely stuff. Hard as nails and long-lasting.

For a free no obligation quote on your wooden decking, pergola or screening needs in Durban or Cape Town, please call us on 031 – 762 1795 or use the contact us form below.