What exactly is a vinyl liner inground pool? How are they built? Are they hard to maintain? Can I get a custom built one? More than likely these are some of the questions that you have and probably many more. If you are beginning your research on a pool, or are already well into the process this article will help to answer your questions.
From Wikipedia, the free encyclopedia:
There are several distinct construction methods for private (home) swimming pools, which are typically called "concrete", "vinyl liner", and "fiberglass". The term "vinyl liner" pool describes the method of lining the interior, not the construction materials, which may be concrete (of various types), pressure-treated wood, or paint-coated or galvanized sheet steel. All construction types have individual benefits and very few problems, the choice being generally up to the individual purchaser.
As mentioned above, vinyl liner refers only to the interior surface of the pool, as colorized chlorinated PVC thermoplastic vinyl may be used as the waterproofing membrane in a number of diverse pool construction methods. Vinyl Liner pools are typically more numerous than other in-ground pool types, especially so in European Union countries, Canada, England and New Zealand.
They are very popular in the Eastern and Southern United States, where this pool type is considered to be a less expensive option to gunite concrete or referred to as a prefabricated pool that can be quickly installed during a single week, but will still provide a durable, quality product that can last for several decades. Designed by Cascade Industries engineer Bob West and introduced to the New Jersey public in 1948, the package pools were introduced to the wider American public by Cascade's (c. 1948–1980) VP of sales Ed Gorman by inclusion the 1951 Sears Roebuck catalog as a do-it-yourself project for US$500.00 + delivery and installation.
In the following years many manufacturers worldwide have produced vinyl pool kits of varying styles and quality that can be transported to sites and installed in only a few days. Designs range from simple (and cheap) prefabricated wooden or galvanized steel walls to high-quality concrete sacrificial shutters incorporating foam insulation that are pumped full of high-density shotcrete and remain in place once the concrete has set (as opposed to the wasteful method of using and discarding plywood boxing that gunite and shotcrete pools employ). Vinyl liner pools are popular with many pool buyers due to lower initial cost, better insulation, the many liner patterns and colors available, a child friendly embossed non-slip finish, and the fact that the liners are treated to discourage algae growth. Most chlorinated PVC thermoplastic vinyl pool liners are .20" and .30" gauge (.50 mm & .75 mm) and are recyclable when they reach their design life (usually 20 to 25 years in moderate climates). Replacement liners can be installed in one to two days, and providing the basic pool shell is of substantial construction, a pool may have several new liners over its expected life, which could be as much as fifty years in the case of a concrete construction.
There you have it. As the article states vinyl pools are a very popular pool. So what exactly are they made of?
All vinyl pools start with a wall panel system. Nowdays they are usually either galvanized steel panels or polymer. We use the galvanized steel panels for our pool kits. I feel that they are a heavier panel and will hold up better over time. The panels do come with a lifetime warranty from the manufacture, but lets be honest here. Fourty-five to fifty years down the road are you going to be concerned that one of the panels finally rusted through. Probably not. In the years that I have been doing this, I have done many liner changes in pools with steel wall panels. Not one of these have been rusted through. Pools that were twenty to thirty years old were in good shape. We have done liner changes on polymer wall pools that were cracked and even had pieces punched all the way out. Polymer wall panel systems are getting better all the time though as manufactures figure out better ways to strengthen the panels.
The wall panel system is where you start if you want a customized shape to your pool. Most manufactures have panels predesigned already to make custom shapes. There are quite a few different shapes and designs you can choose from to get your custom pool, but you can only go so far with a vinyl pool. If you are looking for something with a complete freeform design you are going to be better off with a concrete pool. The main advantage of concrete over vinyl or fiberglass, is the ability to design whatever you want.
Once the panels have been set in place and bolted together the next step is square and level. Very important step here. If the pool is not built square and level there is a good chance your liner will have wrinkles. Once the dimensions have been checked and are good to go the concrete collar is ready to be poured. This entails pouring concrete around the outside of the wall panels at the bottom to lock in the panels with the bracing that has been set. Once the concrete has set up, the plumbing lines are ready to be connected to skimmers and return fittings, along with any electrical conduit for lighting systems if they are part of the pool. Now we are ready to backfill. We at Edwards Pools always use gravel for our backfill. A crushed gravel that is ¾ “ or smaller works the best. With gravel you get better drainage for any groundwater around the outside of the pool. With any type of hole in the ground you are going to get water flowing into it. We install sump systems on all pools to be able to get rid of the ground water if necessary. With a gravel backfill it allows for better water flow to be able to pump it out. With using gravel we also have complete compaction for any type of decking, whether it be concrete or a paver material. This way we do not deal with settling issues on the decking around the pool.
The base material most commonly used for vinyl pools today is a vermiculite base material. Vermiculite is basically concrete without the gravel that sets up to around 750 PSI. A grout concrete mix is a base material that is used also. A grout mix sets up at around 2500 PSI. We use a vermiculite mix for our pool bottoms. We prefer the vermiculite over the grout because it does not set up as hard. Once it has set up we can repair any trowel marks and imperfections to get the cleanest bottom possible. With grout you can not do this. No bottom on a vinyl pool will ever be perfectly smooth. There will be imperfections that you can see, typically when you turn on the pool light. This is where a fiberglass pool wins out over a vinyl pool because you will have a perfectly smooth bottom with fiberglass.
Now we are to the fun part. Dropping the liner and getting water in this baby. Just about everybody thinks this is the hard part of building a pool. As long as your pool was built to specs. in the previous steps this is the easy part. We clean down the bottom of the pool good, and install a foam padding on the inside of the wall panels. This gives a cushioning for the liner as it presses up to the wall panels so that it is not resting up against bare steel. It is crucial that the liner is installed square so that you do not have wrinkles. We use vacs to suck the liner into place, which pulls the wrinkles out. This allows us to see also that we have the liner in square before adding water. If you start adding water and trying to pull wrinkles out as the pool fills, you will probably end up with a wrinkle in the liner somewhere. If you have not sucked the liner into place you do not know for sure if you have it square in the pool. Once you have water in the pool and realize you might need to adjust it, your too late. Unless you pump the water back out and redo it, your stuck.
Now we are ready to do the top decking around the pool and have it finished up. You have the option for different types of decking depending on your preference and budget. Some of the different choices are:
Depending on job situations and conditions, the decking and the liner installation can be interchanged. We have done this both ways. Build the pool and do the decking, then drop the liner, or build the pool, drop the liner, and then do the decking. Either way is fine.
As with any thing there are good and bad things with vinyl pools. Though these lists will not be all inclusive I will hit on a few of the major ones.
Hopefully this has helped you to understand better what a vinyl liner pool is, what they are made of, how they are built, and a few of the pros and cons they have. Good luck and happy pool shopping.