Rooftop Pools

A rooftop pool is quite a different challenge than an in- ground pool. The structural engineers must make sure that what the pool is going to be built on will support the extra weight of the shell of the pool as well as the water. The two types of pools that are suited for this type of pool are (1) stainless steel and (2) shotcrete.  Stainless is quite a bit more expensive.

Challenge

The challenge consists in calculating and controlling a multiplicity of factors from the blueprint stage:

  • Calculating precisely the load that the building can support (work done in conjunction with the main architect of the building);
  • Determining the location where the rooftop pool can be placed without endangering the structural equilibriums of the building;
  • Taking into account the natural and exceptional rocking motions (lateral deflection) of the building (due to factors such as wind, earthquakes, landslides, etc.);
  • Selecting materials that will be light enough to limit the increase of the load but strong enough to hold a massive body of water safely and without leaks;
  • Designing the pool and its access ways to address all safety concerns;
  • Designing the rooftop area for failure events (where does the water go if all hell breaks loose?);
  • Channeling pipes to bring water to the pool and treat it;
  • Calculating the pressures necessary to manage the water flows;
  • Hauling and installing all the heavy construction equipment necessary to build the rooftop pool in an urban environment;
  • Managing the construction site with minimum disruption of traffic on public roadways and inside the property on which the pool is built;
  • Obtaining all the permits necessary for the project to be greenlighted…

The list is long and does not stop at the blueprinting and construction stage, but extends to the mechanical engineering of the pool itself and its maintenance systems, and passing all the safety and regulatory inspections mandated by the local, State and federal authorities to ensure public safety.

Process

Usually a vault is built by the contractor of the building which will “house” the shotcrete structure that is shot inside of it.  This concrete vault is anywhere from 8” to 12” thick and stands about 4’ above the floor.  It is thoroughly sealed and in some instances the general contractor fills it up to make sure it does not leak. Shotcrete pools, even though they have a “waterproof” interior, will lose water through osmosis.  That is the reason that the waterproofing is very important.

To obtain the required slopes on the floor of the pool we use structural foam so as not to put any more weight than necessary on the floor under the pool. The rest of the process is pretty much just like a normal pool.

Another major difference is the fact that the plumbing is (obviously) not underground where it would be protected from freezing.  Therefore, we use variable speed pumps to keep the water moving 24/7.  Since moving water does not freeze, this engineering solution takes care of the problem.

Building a rooftop pool is a major endeavor that takes months of preparation before the first crane goes up. Few pool contractors have the experience, the financial resources, the manpower and the liability coverage necessary to successfully bid and execute projects of this nature.

Cimarron Circle has successfully built three such pools on the rooftops of private buildings located near the University of Arizona, including on the rooftops of two student housing structures.

The following are photos of the rooftop pools built on high-rise student housing buildings in downtown Tucson:

Rooftop Pools