Swimming Pool Construction:What Benefits do PolyBloK Pools provide?

What are the Pros and Cons of Using PolyBloKs in your Swimming Pool Construction Project?

"All that I want is a Hole in the Ground to swim in"

Many people think “All I want is a simple Hole in the Ground to swim in and I’m not going to pay a fortune for it!” - But unfortunately things are just not as simple as that.

It is a sad fact of life that it is much more difficult to get real value for money when constructing a cheap swimming pool than it is when buying a cheap car. There are loads of cheap cars on the market, that will last just as long as an expensive car, but this is not the case with pool construction.

A cheap fibreglass pool could cost you about £2000 for every year that you own it

A fibreglass swimming pool contractor may charge £12 to £15,000 perhaps for a pool that may last 6 or 7 years before you get the dreaded rust marks caused by pinholes in the gel coat. It will then cost say £3,000 to get rid of it - so the total cost including VAT is nearly 20k – or about £3000 per annum over its life. Even if it lasts 12 years the cost will be nearly £2,000 per annum.

When the dreaded rust marks occur you can also call in a fibreglass repair specialist that will charge you another £6,000 to plaster epoxy resin all across the pool surface. Unfortunately this does not really prolong the life of the pool by any substantial amount and is just another way to burn more money.

Another option is to install a new fibreglass pool and then tile it with the mosaic ceramic tiles that are supplied in sheets of various sizes where the backing is a special type of flexible fibre-glasss. However this increases the cost of the fibre-glass pool substantially and does not overcome the problem of the inherent weakness of fibreglass when it is buried in wet, weak soil.

Many Panel Pools on the market are a scam

I think that many swimming pool builders that use panel pools are SCAMMING their Clients.

- Why do I say this?

Simply because the instructions on the panel pool kits often say that the backfill around the pool must be free draining gravel, without any water in it.

In winter and spring in the UK or France, it is impossible to ensure that this gravel, that needs to be placed between the back of the pool wall and the edge of the pool dig, does not get water-logged in the winter. And if the pool needs to be emptied under these circumstancess the walls can collapse because they are not designed for this condition.

When are you most likely to want to empty your swimming pool? - in the spring when your water has gone green during the winter. And when is the groundwater likely to be highest around your pool? - in the spring of course!

They all trumpet their are so called guarantees

The panel pool sales merchants will not tell you that but will trumpet their so called 10 year guarantees.

But if you read the small print you will see that they only guarantee the pool wall components. So any wall collapse will just be blamed on "The Soil Conditions in your Garden" by the swimming pool contractor who can then conveniently walk away from your problem.

And even more importantly, the guarantees only ever provide for "Component Replacement". But just how much is the labour going to cost when first the collapsed pool has to be dug out and disposed of, then a new pool with the replacement components has to be built. By the way you cannot re-use a previously installed vinyl liner - and the guarantees never include a replacement liner. The paving around the pool will also have to be dug up and replaced at a substantial cost.

Circular Swimming Pools and Pools with curved walls

Panel pools and fibre glass pools are rarely constructed as rectangular pools because the design is so close to the knuckle that they have to have curved walls for structural stability at the time when the dry backfill is placed around them before the pool is filled with water. The walls are then stabilized by the water on one side and the gravel on the other. 

The average potential buyer of your property will take one look at the shape (If it is not rectangular)- and say I don't like that - and then discount the value of your property by the cost of replacing the pool with a rectangular one.

Rectangular Pool Kits

You may think - Joe Pool Contractor Limited provides panel pool kits for the construction of rectangular pools.

I know, I know - but some of these kits rely on bits of steel angle being banged into the ground with a sledge hammer. They are then connected to the top of the pool walls by screwed rod tie bars.

Talk about a gimcrack job - if you want to spend £30.000 on the construction of a swimming pool held up by a few screwed rods "You're a braver man than I am Gunga Din" (This is from Rudyard Kipling before you start looking for your prhase book).

The filtration systems on a cheap swimming pool are often unsafe

The filtration system on these "Cheap" pools is often only capable of treating the whole volume of the pool water in 15 to 24 hours whereas this period should be 6 to 8 hours. The result is that the water is not filtered fast enough when the weather is very hot in July and August - result green water and sick bathers whenever the air temperature is above about 28 degrees C.

You need to particularly watch out for pools where the water is circulated through the legs of the pool ladder - these will never circulate the water fast enough to clean it properly when the air temperatures are high in July and August.

The cartridge filter Scam

The sales people also often trumpet the miniaturized nature of their filtration system. What you actually find is that they use a cartridge filter system whereby you are obliged to go back to the pool supplier for new cartridges every few weeks during the summer. In fact on the larger pools you can end up spending 3 or £400 on new cartridges every swimming season!

They will often tell you that cartridge filters will remove finer particles and make the water look cleaner. Frankly this is BS! - If you look after your sand filter by regular backwashing all that you will have to do is replace the sand every 2 or 3 years at a cost of £20 or so.

The really dangerous thing about cartridge filters is that the cost stops them from being replaced. These filters remove the dead skin and other organic pollutants that the nasties that cause illness live on - it must be efficiently removed or the pool will soon become unsafe to use in warm weather.

And what about the Health Risk to Children?

You are Responsible for the Health of every Child that swims in your Swimming Pool

I know that it will always be impossible to prove that it was your fault that Tom from down the road got dysentery, nearly died and infected half the local school with it. But that is exactly the risk that you run when your swimming pool contractor builds a pool with inadeqaute filtration and chlorination systems for use during exceptionally hot summers.

The skimmers never work because of changing water levels

Skimmers are also frequently provided on these pools but they are rendered useless because there is no water level control system. Water levels in any swimming pool area vary all the time because of evaporation and so at the hottest period a year when evaporation is at a maximum the skimmers are most likely not to work simply because the water level in the pool has dropped below them.

And don't even think about what happens to one of these pools if winter temperatures get low enough to produce 100 mms of ice on the pool - and the pressure it produces on the pool walls!!!

I have lost count of the number of completely useless swimming pools that are less than 10 years old that I had been called in to look at.

Swimming pools that look knackered nearly always have a negative value because the old pool has to be dug out and disposed of before a replacement can be constructed..

The owners of every single one of these pool thought that they had been ripped off by either the original swimming pool builder / swimming pool contractor or more frequently by the people that had sold them the house!! It's a sad reflection on the modern pool industry that many people often have to sell their house at a substantial discount because the expensive pool they have bought and boasted about is a pup!

Are you a discerning buyer?

So one of the first things to do is to be decide whether you are a "Hole in the Ground Type of Pool Buyer" or someone that is much more discerning.

After you have decided that you are either going to find more money for a better quality pool or abandon the pool project completely, you then need to decide what sort of swimming pool to construct.

Introducing the old chestnut - are tiled swimming pool's the best

This is probably an appropriate point to introduce the old chestnut - are PVC vinyl liner swimming pools an inferior product to a tiled swimming pool?

Many people reading this may have a preconceived idea that tiled swimming pools are far superior to PVC liner swimming pools.

In fact, Looking Good, is about the only advantage that tiled swimming pools have!

It is very important to understand that tiled swimming pools are only better from the point of view of aesthetics. In other words there is no doubt that they look a lot better - but that is about the only advantage that they have!

However in just about every other respect including:-

Vinyl liner swimming pools with a concrete structure offer the best value for money and so in most cases are a much better choice than tiled swimming pools.

If only money were no object

If the money were no object and you could spend what it takes to construct your dream swimming pool, most people might choose to install a 20 or 30m long indoor swimming pool and line both the pool and the surrounding areas with expensive Italian tiles.

However, the size of your garden, the attitude of the local planning authority and the amount of money that you have available will inevitably circumscribe what you can do. And are indoor swimming pools always the best choice?

How are you going to use the swimming pool?

If you just want to swim for 365 days a year then an indoor swimming pool is obviously the right solution and it is then just a question of deciding how big the pool should be. Exercise pools can be set up in many ways and there is a whole website page on this topic where you can read about it.

But if you want the swimming pool to be the focus of your social and leisure activity throughout the period when the weather is good enough to be outside an indoor pool may not be the best answer.

Obviously the pool water needs to be heated but even that is not that costly with a modern heat pump.

Indoor pool humidity levels can be very unpleasant

Let's face it the humidity levels around an indoor pool can be very unpleasant during warm summer periods and in these circumstances an outdoor pool with designer lighting might be a much more attractive proposition.

And do you really want to be indoors in a swimming pool when the weather outside is absolutely beautiful and there is a cooling breeze on your skin when you get out of the pool.

So many people take the view, that I share, that the benefit of being able to swim for 365 days per year is far outweighed by the benefit of having a beautiful outside swimming pool during the summer months when you can really enjoy it.

And then what about the cost?

The price range of a vinyl liner 10 x 5 or 12 x 6 metre swimming pool is going to lie in the range between £30,000 and £50,000 depending on the level of the accessories to be provided including automatic floating covers, automatic pH control and chlorination and the surrounding landscaping.

On the other hand, a tiled swimming pool of the same size is going to cost about the same without the accessories. And so the total cost by the time you add in all the accessories is going to be in the £80,000 to £100,000 range.

If you want to put the swimming pool indoors the cost can easily be double those indicated above -and more - depending on the quality of the building and its fittings.

By the time you read this far, I suspect that you will already know pretty firm idea as to whether you want to build an indoor or outdoor swimming pool.

I'm also pretty sure that you will be thinking to yourself::-

"How do I make up my mind whether to construct a tiled swimming pool or a vinyl liner swimming pool?"

"If I go for a vinyl liner swimming pool - How can I make sure that the structure will be adequate"

To help you make up your mind about this I'm going to tell you about the history of swimming pool technology so that you fully understand the differences between the two methods of swimming pool construction.

The history of swimming pool construction

The history of swimming pool construction can be divided into two distinct eras - Before PVC Liners and After PVC Liners.

Before Vinyl Liners were invented

Before Vinyl Liners there were only two methods that professional pool builders could use to construct swimming pools.

Method 1 required the construction of a very heavy thick high reinforced concrete tank using conventional concrete. The walls were 200 to 300 mm thick and the concrete floor slab 300 mm thick. The swimming pool builders predominantly used heavy metal or timber form work that required a large highly skilled labour force and a lot of concrete and reinforcement.

Method 2 required the construction of a quite thin reinforced concrete tank using very high strength "Gunite" dry concrete that the swimming pool contractor sprayed onto formwork using high pressure compressed air.

The early concrete structures were very costly

Neither of these types of structure were really suitable for private swimming pool construction because they both require a full scale site investigation and a site specific design by a professional engineer as well as teams of highly skilled site building operatives and expensive equipment.

They had many drawbacks

There were other drawbacks that still apply today:-

The concrete shell needs to be left to "cure" for at least six weeks before the pool lining can be installed

The concrete shell is never really totally waterproof and so needs a "lining" that normally consists of a cement-based mortar with costly special additives that needs to be trowelled on by skilled plasterers

The lining itself must be left to cure for at least another four weeks before the tiles can be glued to it

The tiling and grouting will also take several weeks to complete and will then need to be left for about another four weeks before the swimming pool can be filled with water.

They take six months to build

When the actual swimming pool construction time is added in, as well as the installation and commissioning of the pool equipment, this type of swimming pool tends to take at least six months to build.

These factors mean that these types of swimming pool were far too costly for most domestic swimming pools buyers - and that is still very much the case, even now, simply because the technology of this type of pool has not changed.

Despite all this, there are still a large number of both these types of pool being installed in the UK today by swimming pool builders and contractors, although the Gunite has largely been replaced by the wet concrete Shotcrete Process. This is similar except that wet concrete is pumped at high pressure and velocity onto the sub-soil or formwork.

The initial installation costs of these swimming pool types are very high but there are quite a few other drawbacks as well.

The real drawbacks of tiled swimming pools

They are uncomfortable

It is a fact that tiles are just not as comfortable to walk on as a PVC liner pool that always incorporates a substantial felt layer similar to that used under your carpets at home.

The grouted joints need frequent attention

Even if you have automatic pH and chlorine control, to accurately control the swimming pool water chemistry, the grouted joints between the tiles will probably need to be raked out and re-grouted within about 6 to 7 years. This is a pretty expensive, disruptive and lengthy process and can easily mean that the pool is not available for a whole summer - because you cannot retile in the winter.

Render failure often causes the swimming pool to leak

The waterproofing render needs to be very carefully applied by by a highly skilled building operator because if the render allows water to get through it the swimming pool will leak. It is always the devil's own job to find the source of the leak in these circumstances.

Please remember that the tiling does not hold the water in the pool - it just provides a decorative surface. This is quite unlike the vinyl liner that holds the water in the pool and also provides the decorative function.

Pool water attacks the concrete shell

Even if a leak itself is not large the slightly acidic chlorinated water will soon attack both concrete and reinforcement thus reducing the actual strength of the structure itself.

When this happens the tiles tend to spall off the walls and complete re-tiling will be necessary.

The water line along the tiling is very difficult to keep clean

The tiling, particularly along the water line is also prone to getting dirty, particularly, if pool users smother themselves with the suntan cream that promotes rapid tanning!

Limescale deposits are a problem

Calcium carbonate limescale deposits also tend to build up very rapidly in hard water areas. These are very difficult to clean off without removing the shiny surface glazing of the tiles and this surface removal promotes even more rapid growth of carbonate deposits.

Why would anyone install a tiled swimming pool?

You must be already asking yourselves why anyone would install a tiled swimming pool - well I often wonder myself!!

But to be fair - A beautifully built tiled pool with up market Italian ceramic tiles, and built by a professional swimming pool contractor does look the "dogs b........s"

The cheaper tiled alternatives were even worse!

In order to reduce costs many pools were also built using concrete block walls that were constructed on a concrete base slab that also formed the floor of the pool. These were mainly built on a DIY basis or by a builder working for his client. Some of these pools held water but most did not.

Many different materials were used to try and waterproof the pool walls but most only worked for a time and then a slight structural movement would take place that caused the pool to leak. Once the leak got too bad the pool would be left to fall into disrepair.

Putting very expensive tiling on an un-reinforced concrete blockwork wall must be about the most foolish way to waste your money that there is - but many people have done this in the past.

What about a fibre glass lining?

Fibre-glass lined concrete pools were also installed by many pool builders at one stage, but they have always been looked on as a second class cousin to tiled pools because the fibre-glass industry has never really developed a high performance product that looks as good as high quality tiling.

I have seen fibreglass lined pools that were built and never actually filled with water because the fibreglass was of such poor quality that the pool could not actually be filled up because it leaked so quickly!

There was a strange theory going the rounds in France at one stage that a fiber glass lining would continue to hold water even after the pool shell had cracked! At the end of the day there are only two things that you can do with a pool like this - install a PVC vinyl liner or fill the pool in!

Swimming Pool Construction after PVC Liners were invented

The introduction of PVC vinyl liners allowed swimming pool contractors to develop pools that were not as rigid, stiff and costly as the concrete tank type pools where the actual structure had to be designed to hold water.

And so the invention of the vinyl liner has been the most significant thing that has ever happened in the swimming pool construction industry.

Liners are now produced that are suitable for every type of pool - from the heaviest used commercial pools - to the pools with the highest environmental loading from ice, snow and the sun.

PVC liners are the best thing since sliced bread

To be frank any swimming pool builder that is not using PVC liners is providing his Clients with a sub-standard product unless pool aesthetics are the dominant reason for having the pool in the first place!

The only downside of vinyl liner technology is that manufacturers of the modular panel pools have jumped onto the pool construction bandwagon and produce an array of panel pool products that are fine for above ground pools - but are entirely unsuitable for buried in-ground pools where they are now frequently used - as discussed above.

The structure of a PVC Liner pool has to be stable enough to be absolutely certain that structural failure will not occur but not totally rigid like the structures required for tiled swimming pools. This is because minor structural movement does not lead to leaks because the water proofing is provided by the PVC Liner.

Three important structural implications not generally realised by the swimming pool construction industry

There are three important structural implications from this that have never really been fully appreciated by many professional pool builders.

These are:-

So now a professional swimming pool contractor could provide:-

  1. A pool floor covered by a simple sand / cement screed finish without any reinforcement or structural connection to the pool walls 
  2. Free standing pool walls on a strip footing around the pool
  3. Structural concrete pool terrace slabs around the entire pool perimeter that are supported at one end by the pool walls and at the other end by the firm ground outside the pool excavation.

Why swimming pools on a slope can have very cold water

It is also odd that, swimming pool builders have never bothered to provide some insulation in the swimming pool walls to reduce heat loss from the swimming pool water.

In fact, many swimming pool contractors have built pools on sloping sites and have been very puzzled because the water in the swimming pool is always very cold. The reason for this was that whenever a swimming pool is built in an area of groundwater flow the groundwater is constantly taking the heat away from the pool water. In these circumstances, the swimming pool walls need to be insulated and a drain installed in order to reduce the flow of groundwater around the swimming pool.

What would be the perfect vinyl liner swimming pool?

All that is needed to provide a very reliable, very robust, warm water, very attractive PVC liner swimming pool is a method of constructing the pool walls that is rapid, easy, straightforward, rugged, robust, economic and also insulating to retain heat within the pool.

So we know what sort of pool we want to construct

We also know that the construction and installation of the swimming pool is a complex process to manage becasue:-

"Even if we go for the relative simplicity of a vinyl liner swimming pool I still have to go through the process of getting the drawings done, finding a reliable swimming pool installer and supervising the construction of something that I know absolutely nothing about"

"And what happens if we hit groundwater when we excavate for the pool?"

"And what happens if the swimming pool installer goes bust halfway through installation?"

Would'nt it be fantastic if ..........

we could find someone that:-

The French had the answer all along

After years of research and the construction of nearly 50 pools in the difficult ground conditions of SW France Bluepools has developed a new pool structural system that takes full advantage of Vinyl Liner Technology.

Swimming pool builders and swimming pool contractors in France have been built using this system the past 20 years by "Virginia Piscines” and “Esprit Piscines”

The French system with bells and whistles

Bluepools has developed and refined the French system by incorporating a horizontal reinforced concrete slab element that is connected to the top of the insulated reinforced concrete walls and spans from the top of the insulated wall to the undisturbed ground that surrounds the pool excavation. We call these the "ArConWall" slabs.

These slabs both support the paving that is laid around the pool so that it does not settle and also support the tops of the walls against ice expansion pressure in the winter.

Most importantly they also prop and hold the tops of the swimming pool walls so that a PolyBloK pool can be emptied at any time without any risk of wall collapse.

PolyBloK calls are now available in the UK!

We call these pools PolyBloK pools and are now introducing them to the United Kingdom swimming pool market. Every pool is installed with:-

  1. Automatic chlorination
  2. Automatic watertight and level control
  3. Sand Filtration system providing a complete pool water change in six hours
  4. The ArConWall slabs
  5. Top-quality vinyl liners with a 10 year guarantee

The ARConWall concrete slabs do three things:-

We call this structural system the "ARConWall System" an ancronym from "Anchored Reinforced Concrete Wall" . Every one of our pools is completely surrounded by these ARConWall slabs that ensure that under ice loading your new pool will not be damaged beyond repair.