1. Planning considerations for your Shade Sail
There may be opportunities for creating attachment points for your sail on existing structures, or you may need to install steel or wooden posts.
1.1. Movement of the Sun
The sun rises daily in the east and sets to the west. As the seasons progress, it also moves from low in the sky during the winter months to high in the sky during summer. Your structure should be planned to provide maximum shade protection during the height of summer, or summer solstice, as this is when it will be needed most.
1.2. Shade Sail Shapes
Shade Sails work best and look more appealing when they are designed to have a “twist”, or hypar effect. This is where the fixing points, being posts or brackets, are created at different heights, such that the sail is then twisted in order to fit.
A flat shade sail is harder to tension correctly, it flaps in the wind, and in times of heavy downpour can hold water, thus putting excess load pressure on the fixing points and stretching the fabric.
If the shade sail is a triangle or is installed in a flat plane, a minimum fall of 1:4 is required to shed water.
If two or more triangle sails are being considered, remember there will be hollow in their edges so an overlap will be required for total shade.
Shade Sails use the hollows/curves in the edges to set up tension through the sail. As the corners of the sail are tensioned the edge hollows/curves try to straighten, in turn pulling the fabric tight.
The twisted shape in a sail is not just for looks, by adding the high and low points into the sails the shape of the sail also pulls tension through the fabric by the high points trying to pull the fabric up and the low points trying to pull the fabric down. By inducing this twist the set up tension in the sail is also reduced as you are no longer just relying on the edges to tension the sail.
1.3 Shade Sail Size.
The actual Shade Sail will be smaller then a straight line between your fixing points. In some corners of the sail (nominated by you) we design 300mm (12”) short of the fixing points to allow for a turnbuckle which is used to tension your sail. The sail edges also are not straight, we design a necessary hollow in the sides of the sail. You need to take this into consideration if you plan to have more than one shade sail. For these reasons you should install your fixing points further apart from each other than the actual area you desire to shade.