We at Polypool strongly believe that every pool in the ground should be insulated.
In this section you will find a list of frequently asked questions that we have received over the years from people like yourself looking to build their own swimming pool using our system.
What is the difference between a 75 system & 125 system?
How does the Polypool system’s insulation actually work?
The Polypool concept is based around heat conservation and simple scientific facts.
One of the laws of physics states that heat flows from a warm body to a cold one.
The average ground temperature anywhere in the UK is around 10-12 degrees centigrade at any time of year. The average swimming pool water temperature is between 27 and 30 degrees Centigrade.
Heat is lost from a heated swimming pool from the surface of the swimming pool and through the walls and floor. The largest amount of heat lost is from the surface which is at its greatest whilst the swimming pool is in use. This can be substantially reduced when the swimming pool is not in use by the application of a well insulated and fitted swimming pool cover. You must consider that your swimming pool will only be used for a an average of 3 to 4 hours a day so will be covered the rest of the time, which represents over 20 hours in a 24 hour period.
All pools in the same location will lose the same amount of heat from the surface. The construction of the walls and floor will make a huge difference.
Heat lost through the walls and floor is continuous and is dissipated into the surrounding soil. This is dependent on three basic factors:
Area of the swimming pool walls and floor;
Difference in temperature between the soil and the swimming pool water;
The heat conducting properties of the wall and floor construction.
The third factor involves the nature and thickness of the materials from which the swimming pool is constructed. Some materials conduct heat better than others do, for instance, concrete, steel or fibreglass conduct heat more quickly than Polypool’s 125mm of closed cell polyurethane insulation.
As heat dissipates into the soil surrounding the swimming pool structure so it is further dissipated outwards through the soil and it is reasonable to base the heat flow calculation on a fairly constant temperature which allows for a steady state heat loss almost all year round.
If the water table is high and the swimming pool construction materials can become effectively saturated this will cause a reduction in the thermal efficiency and an increase in the heat lost. This will not happen to the wall construction of a Polypool because with a steel faced, sealed panel construction this factor is virtually eliminated. The swimming pool water is effectively encapsulated in a “thermos flask”, which dramatically reduces heat extraction into the ground.
Please note that the laws of physics state that heat naturally rises in air and liquids. However heat is transferred in ALL directions in a solid such as concrete, rock, dry clay and dense gravel. Our extensive research has proven that the heat loss through the base/floor of a swimming pool is high under these conditions. Insulation may be placed under the floor screed if required, the cost of which can be recovered in a reasonable time.
If there is static water under the floor then convection comes in to play and the water retains the heat like an insulator. If the water is flowing however, then heat is extracted at an alarming rate and insulation is a must.
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What is included in my Polypool package?
The Polypool kit includes the pool shell (channels, panels), the pre-plumbed flow control (skimmers, inlets, vacuum point and main drains/sumps), the liner, the pipework, fittings, valves, filtration pump, filter vessel, maintenance and cleaning equipment, chemical starter kit and a technical support package. This is everything you need to install your swimming pool apart from the labour and raw materials ie: sand, cement, shingle and ballast etc. Standard extras and add-ons you may consider for your swimming pool include steps, underwater lights, a control panel, coping stones and covers and rollers.
What help and technical information do I get throughout the project?
Every Polypool package comes complete with a technical support file. We provide the customer, the architect and the building contractor (if applicable) with all manuals, drawings, a technical support CD and a telephone helpline. The information supplied includes, excavation plans, swimming pool channel and panel installation drawings, a comprehensive construction manual, pipework and plant room schematics and a CD with hundreds of step-by-step photographs of the construction process. We have supplied over 500 Polypool systems throughout the UK over the past seven years and have an extensive portfolio of very successful and well project managed installations. Case studies and testimonials are available upon request.
What types of swimming pool are available using the Polypool system?
The Polypool package is extremely versatile and is widely used in a number of commercial and domestic projects including leisure clubs, schools, swimming clubs, dive tanks and hotels. The modular panels allow the creation of any size and a variety of angular profiles. The 1.5m panel option offers a swimming pool with a constant depth of 1.35m (approx 4 ½ feet) and the 1.2m panels offer a hopper profile with a shallow end at 1.05m (approx 3feet) and a deep end of anything up to 3m (approx 9 feet). The Polypool system comes in a freeboard and level deck option.
A freeboard system is a swimming pool with skimmers and the level deck is usually associated with commercial pools and the water laps over the side of the swimming pool into a grille and a trough detail. This is more expensive and more intricate to build and relies on a gravity fed filtration system with balancing tanks. The Polypool package can also offer infinity/vanishing edge pools and lap pools etc.
What type of heating should I opt for?
Swimming pools can be heated by way of electricity, gas, oil, geothermal/ground source heat, wood pellet burners, solar or even wind turbines. Renewable and free energy is great but is only suitable for outdoor swimming pools. Indoor pools require a more complex air heating and dehumidification system, which can only operate on gas, oil, geothermal or in some cases electricity. Air to water heat pumps are very popular for outdoor pools and only require an electrical supply to the plant room. As this power supply is already required to run the filtration pump, underwater lights and other swimming pool components this merely means upsizing the cable to accommodate the heater as well. In this case around a 40Amp single phase supply to the plant room is sufficient. Heat pumps should cost no more than £1.50 per day to heat an average size outdoor family swimming pool. We recommend you take advice from a qualified Part P engineer for all such installations. All gas and oil connections must also be carried out by a registered Corgi engineer.
Should I cover my swimming pool?
YES! All pools must be covered when not in use as this will reduce heat loss and evaporation from the surface and cut your running costs by up to 66%. This is even more crucial for indoor pools as evaporation from the swimming pool surface will compromise the environment in the swimming pool hall. Indoor pools require air heating and dehumidification equipment and a swimming pool cover or heat retention blanket will reduce running costs and make the environmental control system more efficient.
What types of steps are available?
You can chose from a simple stainless steel ladder, an external roman end step (semi circular), an external square step or an internal corner step unit. Internal corner steps are usually recommended for indoor pools as they do not take up any of your social/leisure area around the swimming pool when space is at a premium.
What types of extras and add-ons can I have with my Polypool?
The Polypool system can accommodate many extras and accessories. These include underwater lights, fibre optic lighting, LED lights that change colour, Chlorine free systems, automatic water top up systems, counter current units/swimjets and more.
How long does a Polypool take to build?
The swimming pool shell/panels only take a day to assemble and are pre-plumbed in the factory with the skimmers, inlets, vacuum point and lights etc. The overall construction time is based on the individual customer or building contractors schedule and should take no longer than 3 -4 weeks from start to finish including connecting the services and applying the finishes around the swimming pool
How long are the guarantees on the Polypool packages?
The Polypool kit itself comes with a 25 year manufacturers warranty as standard. All other electrical and mechanical components and extras are industry standard products and also come with the relevant manufacturers/suppliers guarantees. These are generally one year on items such as pumps, filters, lights, control panels etc and 5 years on domestic swimming pool liners.
How long should my swimming pool liner last?
Pool liners are supplied in different grades and a large variety of patterns and styles. The standard 20 thou (.5mm) liner is guaranteed for 5 years and should last well over ten years. The manufacturing process for liners has improved the quality of the product dramatically and swimming pool liners are more resilient to UV rays, bad chemical balance and heavier bathing loads than ever before. The slightly thicker 30 thou (.75mm) option should last close to 10 years as long as the swimming pool is maintained and chemicalised correctly. Chlorine free systems are now available at reasonable prices and these will increase the longevity of your swimming pool liner. A commercial grade liner (Alkorplan) is also available for pools with heavy bathing loads. This is an on-site welded liner material, which can last well over 20 years.
How long does it take to get Polypool package delivered?
Around 3 to 4 weeks, on average, from placing your order.
Do you supply specialist labour and on site help?
Yes we can supply labour for specialist stages of the installation such as erecting the swimming pool shell/panels, running and pressure testing the pipework, fitting out the plant room, installing the liner and commissioning the swimming pool system at the end of the project. Please contact your representative for estimates as prices are bespoke to each individual project based on the location of the site and nature of the assistance you require.
Do I need planning permission for a swimming pool?
It is recommended that you contact the local authorities to ascertain whether you require consent. Outdoor pools don’t generally require planning permission unless you are in an area of outstanding natural beauty, green belt, listed building or a conservation area. If you do come under one of these categories then contact your planning office for advice. Indoor swimming pools will be subject to planning and building control applications. This includes new builds and change of use etc. In our professional opinion it is advisable for all indoor or commercial pools to commission an architect to prepare a basic set of drawings for an outline planning application. This will not only facilitate the planning and building control applications process but will allow the main contractor and/or the swimming pool contractor to provide estimates and a specification for the enclosure, the swimming pool and the plant equipment required in the swimming pool hall.
What size swimming pool do I need?
The average outdoor swimming pool in the UK is around 10m x 5m (approx 32 feet x 16 feet). Indoor pools are slightly smaller at around 8m x 4m (28 feet x 14 feet). The rule of thumb is to mark out the swimming pool on the lawn to establish the right size for the plot.
Where should I position the pool?
Again mark out the swimming pool on the ground with a line marker spray to establish the best location for it. Consider any trees that could present problems (root damage and debris etc), ensure that no drains, sewerage pipes, electric cables or soak-aways are in the way. You must also consider an area of the garden where the sun shines the most and prevailing winds may be a factor where the site is more exposed or on high ground. The distance from the services to the swimming pool and the plant room are also a consideration.
What services are required to the site?
The swimming pool plant room will require electricity and either gas or oil for the swimming pool heating system depending on the fuel available on site. All plumbing and electrics must be carried out by Corgi and Part P registered engineers. Mains water can be connected to an automatic water top up system at the poolside but the swimming pool can also be filled and topped up from a simple garden hose if mains water isn’t available at the end of your garden.
What access do I need for plant and swimming pool equipment?
Swimming pools can be dug out with a small 1.5 ton excavator and small dumper trucks are also now available. The space required for access to even the smallest gardens is not as crucial. A micro digger requires a 1m gap down the side of the house although soil removal is trickier. The Polypool panel system is modular so can be broken down from pallets into individual components. These can be carried very easily through to the garden or even in some extreme cases through the house.
How big does the plant room need to be and where should it be located?
The plant room in all cases ideally needs to be a maximum of between 3m away from the swimming pool. It can be further but upgrades to the filtration and flow control may be necessary. For an outdoor swimming pool the plant room needs to be at least 2m x 2m as it will house the plant equipment, maintenance and cleaning equipment, chemicals and toys/inflatables etc. You also need to access the equipment for maintenance. An outdoor swimming pool plant room can be a simple shed or be incorporated into a summer house or existing garage etc. We recommend that the plant room has a 2m height. Indoor pools require a larger plant room and the footprint has to be close to 2.5m x 2.5m. In this case the plant room should ideally be adjacent to the swimming pool enclosure, be adequately ventilated and easy to access.
I want my swimming pool to be indoors, what are my options?
The cheapest swimming pool enclosures are air domes. Whilst these may look out of a 1960’s sci-fi series, they are reasonably cheap and are easy and quick to install and take down. They do not require planning permission either. By placing a space heater inside the dome this should extend your swimming season to around 8 or 9 months of the year.
The next step up is a telescopic swimming pool enclosure, which generally comes in sections with glass or polycarbonate panels on the roof and walls. These types of enclosure, when combined with an air heating and dehumidification system offer comfortable all year round swimming. They are also versatile as they can be opened up on warmer days and the summer so that swimmers can enjoy the sunshine and the pleasures of an outdoor swimming pool. In the winter and colder/rainier days the building is closed to keep out the elements. Telescopic swimming pool enclosures are also great for getting round planning requirements as they are deemed as temporary structures. We have worked on many projects in the past where any type of building was refused planning by the local authorities but a telescopic building was granted permission. These enclosures only require a reinforced concrete slab so they can happily sit on top of the patio slab around the swimming pool without expensive and complex foundations or footings.
More permanent swimming pool enclosures such as standard brick or block constructions require planning and building control applications/consent. Under these regulations insulation and structural requirements will be laid out by the relevant authority. In our professional opinion when planning an indoor swimming pool the customer should commission an architect to put together a basic outline planning design for the project. This will assist with getting estimates from building contractors for the enclosure and also allow the swimming pool contractor to price up the specialist side of the job. The same design/drawings will be used to facilitate the planning and building control applications.
Planning and building control departments will rarely require any great detail on the swimming pool itself but will look at the structural integrity of the swimming pool hall and any interaction of a structural nature between the swimming pool and the foundations of the building. U values and insulation will be stipulated by the local authorities with regards to the roof, windows, walls and ceilings but not the swimming pool.
The most important points to consider when designing and indoor swimming pool are:
Don’t be too ambitious. The larger the swimming pool, the larger the building. The swimming pool size has a knock on effect on the filtration, heating, chemicals, air handling/dehumidification requirement, running costs and more. The average indoor swimming pool is around 8m x 4m.
We recommend a constant depth swimming pool at 1.4m (4 ½ feet). This is easier to build, cheaper to run, more practical to use and is a standard in hotels, spas and leisure clubs
Internal corner steps are preferable as they don’t interfere with the swimming pool surround. Leisure space around indoor pools is usually at a premium so try and make the most of space for social use.
Pool surrounds indoors must be safe. Ensure enough walkway is present on the sides of the swimming pool, which are being most used. Redundant sides to a swimming pool are common in swimming pool design and classed as service ledges. This means you can push the swimming pool into a corner of the swimming pool hall and have a mere 300mm access for maintenance. Main walkways should ideally be a minimum of around 1m. Tiles/flooring should be as slip resistant as possible.
The environment in the pool hall should be sealed so no trickle-vents or other air intake from outside. All doors communicating with other parts of the building or living quarters should be self closing to contain the environment in the pool hall.
An environmental control system is the heart and lungs of any indoor swimming pool. These systems provide pool water heating, air heating, heat reclaim and dehumidification in the pool enclosure.
The plant room must be a minimum of 2.5m x 2.5m to house all the heating and filtration equipment and store chemicals and cleaning kit.
Insulation and a vapour barrier must be present in the walls and ceiling
Materials used as finishes on the walls and ceiling must be chosen carefully as they are exposed to warm, moist chlorinated air, which is highly corrosive. Waterproof render and oil based paints are ideal as are face brick and blockwork. These materials do not deteriorate when combined with the harsh environment of an indoor swimming pool. Stretched ceilings are ideal as they provide a vapour barrier and a finish in one.
Please contact us if you require any advice on any of these points or need help with planning and building regulations.
I have heavy clay on site or a high water table, is this a problem?
No these types of pool system can be built in pretty much any soil or site conditions. As Polypool is not a monolithic pool construction like an old fashioned concrete block or reinforced concrete shell there are very few structural issues. The Polypool shell is self-supporting and independent from the pool floor/base. This means that rising groundwater and clay heave don’t affect the integrity of the pool structure. The backfill being two thirds pea shingle acts as a damper and allows for movement around the pool without causing structural problems due to heave etc. A simple French drain can also be built alongside the pool in cases where ground water levels are high or vary throughout the year. It must also be borne in mind that the huge pressure exerted on the pool walls and floor is also equalising any pressure from the ground or ground water present on site. Please contact our engineers if you have any specific site conditions and need guidance.
If you have another question which is not listed above please call us on our advice line on
01489 890800 or alternatively contact us