The structure was made with treated pine, which is much cheaper than more durable timber such as meranti but is still weather-resistant.
For Piet Steyn of the Zevendal Estate in Kuils River near Cape Town who built this pergola, CCA-treated timber was sufficient. The acronym refers to the copper, chromium and arsenic in the solution in which the timber is soaked – this gives the wood its distinctive light green colour. Depending on where and for what the timber is used, the strength of the CCA mixture can be adjusted and is indicated with ratings from H2 (internal use such as roof trusses) to H5 (outdoor use, in contact with water). Anything higher than H3 is suitable for outdoor structures.
1 Each of the crossbeams is set in a joint that Piet and a helper from PG Handyman sawed in the support beams beneath them.
2 Bluegum latte form the ceiling of the pergola. They might not be waterproof, but the garden furniture is water-, wind- and weather-resistant. “We were more intent on creating shade than providing protection against rain,” says Piet. “Luckily, the angle at which the sun shines means we get excellent shade under the pergola.”
3 The supporting beams rest in a recess made by cutting the central plank of each pillar shorter; a great way to make a joint in a jiffy.
4 The six pillars of the pergola each consist of three 10cm-wide treated pine planks bolted together.
5 The pillars rest on U-brackets which have been set in concrete so that the wood doesn’t touch the soil and stand in water when it rains. For extra protection, you can treat the wood at least once a year with a product such as Woodoc 35 for a low-gloss finish or Woodoc 55 for a gloss finish. These products are available in a variety of colours, simply choose the colour you prefer.