In ground swimming pools should always be built by professionals, but how do they do it? let’s assume that all of the leg work going into the build has already been done (ie. the sale of the pool, the planning stages etc.) This brings us to the start of the dig.
This is the part of the process where the builder will actually break ground and start removing dirt. Typically this part will be completed in one day. In some cases they may actually get to building the pool. However before they get that far they will need to make sure that the dig is to the specifications of the plan. This means that if the plan dictates that the pool be 8′ deep in the deep end, then the dig should reflect that. However, they have to allow for 2″ of bottom material. The bottom material is typically either vermiculite, or a sand/ cement mix. So technically they would have to over dig the pool by at least 2″. They would have to be careful not to over dig it too much because you cannot replace dirt that has been taken out. If the pool is over dug too much they will have to bring in stone to bring the dig back within specs. Throughout the dig, someone will have to check the depth with a transit (laser) to ensure that it is being dug correctly.
At this point the builders will begin to assemble the pools walls. The pool walls come in individual panels of different lengths. They will also come with a detailed layout showing which panel goes where. These panels are fastened together with nuts and bolts. Once the structure is built, they will square it (provided that it is a rectangular shape). Next they will stake the corners, then straighten the walls and stake the rest of the pool. Next they will level the pool with a laser/ transit. After the pool has been straightened and leveled, the plumbing and electrical conduit is ran to the appropriate locations. At this point the footer is poured.
The next day they will come back, and install the coping. Once the coping is installed they will backfill, typically with pea gravel or stone chips. If the pool will have an auto cover the auto cover box is installed as well. Lastly they will bond. Copper wire is ran around the entire pool. If the pool has steel walls every panel gets bonded as well as anything else metal within 5′ of the water. Next they do the rebar (sidewalk prep).
This day they will come back and pour the sidewalks. Every foot away from the waters edge the side walk has to fall 1/8 of an inch. This ensures that when it rains the water will run away from the pool rather than into it. Once all of the sidewalks are formed they will pour the concrete.
Prepping The Bottom:
Next they will come back and take the forms off of the concrete. After all of the forms are off, they saw the concrete into sections to attempt to control cracks. Over time the concrete will crack and sawing lines in it will essentially coax the cracks to be where the lines are already placed. After they saw the concrete they pressure spray it to clear off any dirt or dust. Next they prep the bottom of the pool and clean the walls. After the bottom of the pool is prepped and the walls are cleaned they will place stakes in the bottom of the pool to run string for the exact transition points, where the bottom will ultimately be.
This day they will do the bottom by using either the vermiculite or the sand/cement mix. This process usually takes roughly 4 hours to complete. Once the bottom is done, it is time to drop the liner into place. They will start by securing the liner. Once they have the liner completely secured they will use a vacuum to suction the liner tightly to the pool walls. After the liner is vacuumed to the wall they will cut out around the steps, skimmer, main drains, lights and any returns there may be. Once this is completed they are able to begin filling the pool with water!
Auto cover install: If there is going to be an automatic cover installed for this pool, it would need to be completely full. Once the pool is completely full they are able to install the cover and you are ready to enjoy your new pool.
This is just the steps that are taken when pool professionals install vinyl liner in-ground pools. I must insist that if you are planning to have a pool installed you allow a professional to install it. For more information on vinyl liner in-ground swimming pools please check out the rest of my blog.