Negative edge pools, also known as infinity pools, are pools where the water’s edge gives the illusion of blending in with the horizon. There are no edges that can be seen on the “negative edge” since water actually will spill into a basin that pumps it right back to the pool. These are the most beautiful pools in how they look like they stretch on never ending. The illusion is supposed to be dramatic, and will appear that way if done right. The weir, or wall’s edge, should be level at the top and stand without any extra support. The location you choose to install your negative edge pool in should have a beautiful backdrop. Installing a negative edge pool can be tricky. There are a lot of options you can use to get the effect you want. You may need to have an engineer check the pool plans. This install takes just a little knowledge and architectural skills. When the installation is complete, it should give the appearance of a pool with 3 sides, with one side looking like it dropped off. Just a few tools and tips, and you’ll have a negative edge pool installed in no time.
Step 1 – The Weir (or Dam)
This is the foundation of the pool. You can create the weir to be up to 50 feet long. However long the weir is, it will need to be strong. It has to handle the pool’s water pressure, otherwise it will eventually crack and shatter. Keep in mind that the higher the wall is made, the thicker it will need to be due to the pressure it will have to maintain. The higher the wall, the more pressure it will have applied to it.
Step 2 – Materials Used
The material usually used to install negative edge pools are gunite (a cement mixture), mortar and shotcrete (concrete conveyed through a hose). These can be applied in layers. All cement mixtures need to be poured properly and with caution. A steel rebar can be used in the weir for extra support.
Step 3 – The Water Level
The water level should be the same for 3 sides of the pool, and at water level on the weir. This allows it to flow over the “ledge” and recycled to flow back into the pool. The top of the negative edge (weir) should be about three inches shorter than the other 3 walls. This is why it is important that the weir is level at the top. Otherwise, it would look like it has wet or dry spots and that will mess up the vanishing effect of the water.
Step 4 – Pumps
Smaller pumps are energy efficient, but it the wall is long, this could turn into a big expense. The pump will trigger the water to the catch basin below, so it is important to decide how much water will run over the negative edge. You may need to factor in the difference a gallon per minute will make to install the right pump.
Step 5 – Make Sure Pool is Up to Codes
Always check with the local building codes to see if you are within the standards and regulations. You want to stay in compliance with all codes. An architect may need to check your pool area before installation begins.