There are many ways and different techniques that are used to build a vinyl liner in ground swimming pool. The basic process is for the most part the same from builder to builder but each builder has different things they do that are specific to them. Today I want to talk about the building process again and what types of things builders do differently from one to the other. To do this I am going to go through the build process and as I get to something that varies from one builder to the next I will go into more detail about it. Keep in mind there are several ways to do things in the pool building world and they all work just fine.
To begin the builder will mark out where the pool will go in relation to the house and yard. Getting the orientation of the pool right is the first step in the process after the initial agreement to build had been made. This is pretty consistent across the board of builders. They will use stakes and paint to mark out where the pool goes and in which direction the steps will be facing. Next comes the dig. The dig may vary a bit from builder to builder, and more so when it comes to free form pools. With a free form pool the dig drawing will have a lot of different measurements on it that the builder will follow when marking out the pool. These measurements are important to get right if the builder intends to use that drawing to order the liner from. Now because that is the case some builders are very particular as to making sure that all the measurements are correct. On the other hand some builders will be more concerned with just getting the pool to fit the hole. You have to understand that with a free form pool there is some adjustment that can be made. Once the wall panels are bolted together you could easily move a section of the wall in or out. Some builders use this to their advantage and instead of relying on the specific measurements they will move the walls in or out to fit the hole the best they can. Then when it comes to the liner they will take new measurements to go off of and have the liner made to fit the pool rather than trying to build the pool to fit the liner. Either way works just fine and the end result is still a beautiful pool. Another thing that differs from builder to builder is the way they go about setting the wall panels.
The way that I am accustom to setting panels is to just bolt them together on the ground and work my way from one side of the step all the way around until I get back to the step on the other side. Some other builders will go ahead and set blocks or spikes to the correct height and then set the panels on top of them as they bolt them together. I have seen this several times in the past and I think that doing this makes bolting the panels together a bit easier, but every builder that I have seen do this will also double check the height of the panels with a transit at the end and have to do some adjustment anyway. Its hard to tell if doing this saves time, wastes time, or equals out. I suppose it also depends on the dig as well. In reality if the pool is level in the end it doesn’t really matter how they go about it. Another thing that I have noticed is a difference in they way and products builders do and use to do the bottom of the pool.
When it comes to the bottom of the pool there are two main types of material builders will use to make the bottom. Some builders will use a sand/cement mix, while others use vermiculite. Regardless of the product they use they will still trowel it out so that it is nice and smooth. Some builders will put down a layer of stone and put the bottom material right on top of it. Typically when you dig down 8 or 9 feet you will get some ground water. Depending on the severity of the ground water builders will have to do something to ensure that it doesn’t effect the bottom process. I have seen builders simply bury a five gallon bucket full of little holes so that they can easily pump out all the water right before they trowel the very bottom and drop the liner. If the ground water is really bad then some builders will bury a line in the stone that will remain under the pool so they can pump out any water after the liner is is. There is also a difference in when the bottom will be done. Some builders do the bottom directly after they backfill the pool and before they pour the concrete deck around the pool, and some will pour the concrete before they do the bottom. I always did the bottom last, for a couple reasons. One is that it was just easier than having to clean concrete off the liner or out of the pool, and two is because there is less of a chance to puncture the liner if you wait until the end. Again I suppose both ways work just fine and ultimately it is up to the builder to decide when and how they are going to do the bottom.
These are just some differences in the way that pool builders operate. I am not saying that one way is right and one is wrong, just that they are different. I think you should be aware of them in case you were to have a pool built and expect it to go one way and not the other. The bottom line is that if the pool gets finished and looks amazing then however they did it must work just fine. As a former builder I know what it is like to have a homeowner breathing down you neck about the way you are doing things, and I know first hand how frustrating it can be, so let the person you hire to build your pool do what they do and trust that it will look phenomenal in the end. If you have picked a good builder then there is nothing to worry about. These builders have likely been doing this for some time and know what they are doing.