Monthly Archives: April 2013

Wooden Sundeck Built in Gillitts – April 2013

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Timber deck builder Durban

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This was our second deck we built in Durban using CCA pine as a substructure. I can confirm that there is a substantial cost saving using pine as a substructure and provided it is CCA treated to the correct Hazard Level (H level), then it is guaranteed by the supplier and manufacturer against rot and insect infestation for up to 50 years. So at least H3 must be used which is good for outdoors, exposed to the elements and if there are parts of it that are making contact with ground then H4 is better. In fact the cost difference between H3 and H4 is so slight that I am tending to just use H4 throughout as a matter of course to err on the side of caution.

This deck extended from the house outwards about 5m. Half of that 5m length was on existing tiles and concrete so we placed batons of 38 x 76 and the rest of it dropped down about a metre onto soil. We chose 76mm as our width of baton because it brought us up to exactly where we wanted to be in terms of height of the deck in order to clear the bottom of the door. We therefore had very little space between joist and the tiles so there was very little packing to do. When we place batons on the ground as joists, we fix them using a hilti. The hilti is really just to stop the joist moving sideways and not really up or down as once the deck is built the weight of it keeps it from lifting up. However the hilti provides enough fixing power in both directions so sleeve anchors are not necessary. Often the ground on which you are fixing these batons / joists to, is not completely flat and in order to get the surface of the deck level, one needs to shim one end of the baton or joist. This results in one end being higher than the concrete ground level and as such a gap exists between the baton and the ground. Because these batons are relatively thin (between 38mm and 76mm) they are not strong enough in their width to support the deck. They therefore need to be packed with structural grout or a building sand / cement mixture to take up the gap between the baton and the ground.

Timber deck builder Durban

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The rest of the deck was elevated about 1m off the ground so from that point we installed 38 x 114 joists with a main beam running the width of the deck (parallel to the stairs in the picture). We set that back 300mm so that our span between beam and wall was only 1.9m which is the maximum I am happy to go with a 38 x 114 joist.  The rest of the deck was therefore cantilevered by about 300mm.

Deckboards went on without a problem, and we then built the stairs that you can see in the picture. We took a different approach to the stairs that we normally do, or have done in the past. In the past we have secured a beam all the way along the front of each riser. In this case we built treads and risers in line with each joist and then only on the front riser we fixed a fascia beam which was then secured to posts that had been set in concrete in the ground. It was much quicker than, and just as stable as our previous method. The structure that we built can be seen on one of the pics alongside.  The client wanted to leave the sides open as he is planting some indigenous plants alongside to cover the gap thus allowing his access beneath the deck if need be, but once the plants grow they will cover the sides.

Timber deck builder Durban

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This deck was left unsealed as the client wanted the greying effect. I will re-visit it in a few months’ time and if the client is agreeable we can bleach it and high pressure clean it in order to bring it back to its natural colour.

For a free, no obligation quote please complete the form below and I will contact you.  Or you can call us on 082 496 5444.

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Wooden Sundeck, Toti, Durban

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Wooden Sundeck Installer Durban

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We built this wooden sundeck in Toti using CCA Pine, for the first time, as our substructure and decked it using balau deckboards. For a long time I have been using only balau as a substructure. But after some careful investigation I have accepted that a CCA treated pine substructure is as good if not better than a balau one.

The manufacturers of the solution that is used to pressure treat the timber guarantee their product for between 30 to 50 years depending on which manufacturer you use. Provided the company doing the pressure treatment treats it correctly and provided the correct Hazard Level (H level) is used in the correct application, the timber will be guaranteed against rot and insect infestation by the manufacturer of the solution. I will write another more detailed article on CCA pressure treatments, but for the purpose of this article you will need to know what it broadly means.

Wooden Sundeck Installer Durban

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H2 CCA Treated pine is good for roof trusses where it is not exposed to the elements such as rain. H3 treated is good for outdoors such as decks and H4 is good for in the ground or in contact with wet soil. H5 is good for in salty water and is normally a combination of CCA and creosote treatment. H2 is commonly sold off the shelf at most timber yards. H3 and H4 is more specialised so one needs to find a supplier who is regularly treating to H3 or H4. Under no circumstances should H2 be used as a substitute. It will rot within a few years. Simple. Do not use it in decks, keep it for the roof.

Wooden Sundeck Installer Durban

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In order to activate a guarantee against the manufacturer one would need to take photos of the deck going up ensuring that the correct H level is used, an audit process would need to be completed on the company treating the timber and the build would probably need to be registered with the manufacturer and possibly inspections conducted during the build. So although it is possible to activate a guarantee, it is not really practical as the substructure will go up in 2 days and the deck will be done in 5 days. However, if the manufacturer is willing to offer this sort of guarantee, then we can safely assume that the timber we are using will hold up to its promise. In a nutshell, H3 or H4 treated CCA Pine is suitable for a substructure for a deck and may very well outlast a balau substructure. I would not be too keen to use it as deckboards for two reasons. Although it won’t rot or get eaten by ants, it will expand and contract a lot more than balau which will result in checking, cracking, warping, bowing etc. over time. The second reason is that because it is half as dense, one needs to use a 32mm thick deckboard as opposed to a 19mm deckboard in balau. So twice as much timber is used and the cost is actually slightly more in pine per square metre than balau. So why not use balau in the surface? It is much better looking and much more stable (i.e. it remains flat for many more years).

Wooden Sundeck Installer Durban

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The cost saving in using CCA pine vs. balau in the substructure is great and this allows me to keep my prices low whilst still providing a quality product. The CCA Pine will last as long if not longer than the balau substructure if the correct H grade of CCA pine is used.

All areas that have pine exposed are clad with deckboards so that the pine is not visible. Balustrades remain full balau.

For a no obligation quote on wooden decks, balustrades, pergolas and any other outdoor timber construction, please complete the form below and I will get back to you.  Or you can call us on 082 496 5444.

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