How to Build a Vanishing Edge Pool
A vanishing edge pool creates a dramatic illusion if it is done correctly. If this is not done well then the wall will be obvious or the water coverage is uneven. Ultimately the weir needs to be strong enough so that it can stand without any additional support and the top of the weir should be level and shaped so that it suits the surroundings. Basically the pool looks as if one edge of the pool drops off and there are only 3 sides to the pool.
Step 1 – The Weir
This is the basis of the entire pool. These walls can be very long, up to 50 feet, and need to be strong enough to deal with the water pressure from the pool. Normally it should be at least 12 inches thick. If the weir is not built properly then it can crack over time. There are many construction issues with this type of pool and building and architectural knowledge is needed.
Step 2 – Height
As the height of the wall increases, the thickness of the wall will need to increase. This is because of the pressure that will be on the wall. There is more pressure applied to an 8 foot wall versus a 4 foot wall.
Step 3 – Material
The type of material that is used will depend on the environment as they all with contract and expand at completely different rates. Traditional materials will include mortar, shotcrete and gunite. Sometimes these may even be applied in layers. If using cement then it is important that it is poured properly. For additional support it is possible to use steel rebar within the weir.
Step 4 – Level
The top of the weir should be 3 inches less than the surrounding elevation. This will ensure that the water will cover it and create a natural looking edge. Make sure that the entire top of the weir is level. If the level is off then the edge may have wet and dry spots which kills the vanishing effect.
Step 4 – Pumps
It is best to use as small a pump as possible to save on energy. Ultimately the longer the wall the greater expensive this will be as even a change of a gallon per minute will equate to large costs. The cut of the weir will also affect the pump as most will bevel the weir so that the water runs toward the catch basin. Think about how much water you want running over the weir. Look into how much difference a change of a gallon per minute plus or minus will affect the cost and then buy and install the appropriate pump.
Step 5 – Options
There are many different things that can be altered in order to get the desired effect. Creating your own vanishing pool is tricky, but if you have the knowledge and architectural know how then it is possible. Check with you local building code as it may be necessary to have the plans for the vanishing pool checked by an engineer or architect before actual construction can start.