This was an interesting wooden pergola we built in Durban. Most often pergolas are built using planed all round pieces (PAR) in the traditional pergola design which is vertical posts to support the structure and horizontal purlins of varying width and thickness to cover the top. Wooden pergolas don’t really offer any functional benefit as the rain still comes through and it offers limited sun protection depending on the density of the purlins above. This one however offered both protection from rain and sun yet still allowed light to come through.
We built a structure using H3 CCA Pine which is guaranteed for 50 years against rot and insect infestation. On top of this we placed polycarbonate roof sheeting which we got from Modek. We used their bronze translucent one so that it breaks the sun yet still allows light through and of course offers protection from rain. It is best to use custom-made lengths so as to avoid any joins which would need to be waterproofed. It is not sufficient to overlap them in the direction of the fall. Because the angle or pitch of the roof sheeting is relatively gradual, the wind can blow the water backwards, up hill and through the joins. So it must be waterproofed to avoid any leaks. It is therefore much better to use one full length, the same length as the structure itself.
Once our roof sheeting was on we installed thatching laths beneath with no gaps between them. These laths vary in diameter from 20mm to 35mm. So one needs to install them head to toe to limit the size of the gaps between them. This way they become quite dense so that one can’t see the structure or roof sheeting from beneath, but they still allow enough light through. In other jobs we have installed them with as little as half a laths diameter gap, but that still allows quite of lot of visible roof sheeting from beneath. It is therefore better to stack them tightly up against each other.
After these we clad the sides to cover or hide the pine we used with balau deck boards. The balau is a much better looking wood in terms of grain, colour and the straightness of each board. Balau is very stable and will tend to warp or cup less than pine over the years. So the appearance of the structure will remain flat and square a lot longer than pine.
The final product was a rustic looking pergola which offered protection from sun and rain yet still allowed natural light through. The client later installed a sound system and lights beneath. They had a pizza oven installed and a gas braai with a bar area which made for a very nice outdoors entertainment area which was protected from the elements.
For a free no obligation quote on pergolas or other decking needs as well as floors or laminates please contact us on 031 – 762 1795 or you can use the form below to e-mail me.