Hot Tubs and Spas - Frequently Asked Questions

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  • Q: How much will my hot tub or spa cost to run?
  • Q: What is the difference between a hot tub and a spa?
  • Q: What size hot tub or spa do I need?
  • Q: How many people will fit in my hot tub or spa?
  • Q: Where should I locate my hot tub or spa?
  • Q: Can I position my hot tub or spa indoors?
  • Q: What type of base is suitable for a hot tub or spa?
  • Q: What about drainage around a hot tub or spa?
  • Q: How is the delivery of my hot tub or spa arranged?
  • Q: How is the delivery of my swim spa arranged?
  • Q: Is a hot tub or spa suitable for DIY assembly?
  • Q: Can you commission my hot tub or spa for me?
  • Q: What are the electrical requirements for a hot tub or spa?
  • Q: What are the plumbing requirements for a hot tub or spa?
  • Q: What is the best surface material to use in hot tubs and spas?
  • Q: How do hot tubs and spas work?
  • Q: What are the health benefits of a hot tub or spa?
  • Q: Can I use my hot tub or spa all year round?
  • Q: How is the water in hot tubs and spas kept clean?
  • Q: How often should I change the water in my hot tub or spa?
  • Q: How much weekly maintenance will my hot tub or spa require?
  • Q: How much other maintenance will my hot tub or spa require?
  • Q: How can I reduce the cost of running my hot tub or spa?
  • Q: Can a hot tub or spa be left unused for a long time?
  • Q: How powerful are the electric motors in my hot tub or spa?
  • Q: Is durawood suitable for use in hot tub cabinets?
  • Q: Is planning permission required for a hot tub or spa?
  • Q: Is building regulations approval required for a hot tub or spa?
  • Q: How should I maintain my timber hot tub cabinet?
  • Q: What is western red cedar?
  • How much will my hot tub or spa cost to run?

  • There is very little reliable information available from manufacturers regarding the electrical consumption so we carried out our own study. The cost is subject to many variables including the average temperature outside, the water temperature inside, the size of your hot tub or spa, the frequency of use and the overall duration of use. Based on a price of 12p per unit of electricity we established a typical cost of £259.74 per year or £4.99 per week or 71 pence per day for an average size residential hot tub subject to normal use. Our figures assume electricity consumption based on the combined average annual consumption figures quoted in 7 US surveys which tested the electrical consumption of hot tubs and spas. Regarding the cost of the chemicals required, hot tubs and spas are significantly cheaper to run than swimming pools because there is a much smaller volume of water. The exact usage varies according to the size of the hot tub or spa, the frequency of use and the overall duration of use. The cost of the chemicals is normally less than half of the cost of the electricity.
  • What is the difference between a hot tub and a spa?

  • Originally hot tubs were made from wood and spas were not. Nowadays the differences are blurred. Hot tubs and spas are both designed to provide relaxing hydrotherapy in exactly the same way and both include a heater, pumps, therapeutic jets and water filters. At Summer Garden Buildings if the cabinet is made from wood or looks like wood we normally describe it as a hot tub but if not we normally describe it as a spa - unless its a swim spa, in which case we always describe it as a swim spa whatever the cabinet is made from!
  • What size hot tub or spa do I need?

  • You should consider the maximum number of people who are likely to use it. An extra seat or two is bound to be useful so buy the biggest hot tub or spa you can afford provided that it fits comfortably in the space available. There are no precise guidelines regarding the size. Often the size of the hot tub or spa is dictated by the space available. At Summer Garden Buildings we offer a wide range of sizes to suit every space.
  • How many people will fit in my hot tub or spa?

  • It is standard practice within the hot tub and spa industry to quote a maximum number of people which is higher than the number of seats. We assume that this practice was originally conceived for marketing purposes. In most cases the figures quoted assume that 1 person is not seated although for larger hot tubs and spas the figures may assume that 2 people are not seated. It is perfectly possible to enjoy bathing in a hot tub or spa without being seated. However, it is unlikely that your hot tub will ever hold more people than the total number of seats. A further complication is that lounger seats generally take up the space of 2 normal seats so any hot tub or spa with a lounger may sound smaller than one without. At Summer Garden Buildings we quote both figures. We quote the theoretical maximum number of people so that you can compare with others on a like for like basis, but we also quote the total number of seats which is a more realistic figure.
  • Where should I locate my hot tub or spa?

  • Ideally hot tubs and spas should have a clear space 1 metre wide on all sides, if possible. This ensures good access to the equipment for servicing and maintenance such as changing filters. In reality this is often not practical and at many sites it is not needed. A reduced clearance may be possible on one or two sides. At Summer Garden Buildings we recommend that hot tubs and spas are positioned directly onto the ground and not buried in the ground or under decking. If you build decking around your hot tub you should ensure that there is good access to the equipment. Hot tubs and spas should not be positioned under overhead wires or near electrical appliances.
  • Can I position my hot tub or spa indoors?

  • If you intend to position your hot tub or spa indoors you should consider whether the floor will bear the weight. You should also ensure that the door openings are large enough. Many of our hot tubs are delivered fully assembled as a complete ready made cabinet. You should also ensure ample ventilation because hot tubs and spas produce a lot of steam.
  • What type of base is suitable for a hot tub or spa?

  • All hot tubs and spas need a substantial base. The base should be solid, square, flat and level to ensure that your hot tub or spa is properly supported. Paving slabs or concrete are ideal. An existing patio is normally suitable provided it has been built soundly. A solid concrete base is more permanent and normally more expensive but it provides an excellent base especially for a larger hot tub or spa. Paving slabs are more practical and cost effective, especially for a smaller hot tub or spa at the far end of the garden. If you intend to position your hot tub or spa on timber decking you should ensure that it provides adequate support. When filled to capacity a 4 seater hot tub weighs around 1000kg or 1 tonne and a 7 seater hot tub weighs up to 2500kg or 2.5 tonnes. The base should be no smaller than the external size of the cabinet.
  • What about drainage around a hot tub or spa?

  • Water should always drain away from hot tubs and spas. You should not position your hot tub or spa in a low area because melting snow or rain could flood the area and damage equipment such as pumps.
  • How is the delivery of my hot tub or spa arranged?

  • You will receive advance notice of the delivery day either in writing or by telephone. If it is not convenient you can postpone the delivery with reasonable notice. Some of our smaller spas are delivered flat packed for DIY assembly. These are normally easier to deliver. By contrast, many of our hot tubs are delivered fully assembled as a complete ready made cabinet. The cabinets are bulky and it is not possible to disassemble them. A typical 4 seater hot tub weighs up to 300kg dry. A typical 7 seater hot tub weighs up to 500kg dry. Delivery requires a large lorry. Ideally the hot tub will be placed on a trolley, either on its base if the access is wide enough otherwise on its side. An opening is requred which is the width of the cabinet plus a clearance of 2" or 50mm to each side. If the height is restricted around 18" or 450mm should be allowed for the height of the trolley. The route should be reasonably flat with no steps or steep slopes. Sharp corners can also be a problem in some cases. If you think your access is unsuitable please contact us for further advice.
  • How is the delivery of my swim spa arranged?

  • Swim spas normally require a crane to unload the spa and lower it onto the base. A locally based crane service is normally the most effective solution so it is normally assumed that the customer will organize this. Normally the delivery is arranged with whoever is providing the crane.
  • Is a hot tub or spa suitable for DIY assembly?

  • Some of our smaller spas are suitable for DIY assembly. Assembly is a straightforward and satisfying project for any DIY enthusiast. These spas can normally be installed with only basic tools. Particular care is required when handling sharp items and good quality gloves should be worn at all times. You should not attempt to lift heavy sections without a helping pair of hands. Remember that extra time spent preparing a good base is normally repaid with time saved later on during the installation.
  • Can you commission my hot tub or spa for me?

  • Yes, we can fully commission many of our hot tubs. The price includes filling the the hot tub with water and chemicals, testing the water chemistry and setting the temperature and filtration cycles. A full demonstration of all functions and chemicals is also included. Your hot tub is commissioned at the same time as the delivery which is arranged by appointment with you. Suitable access, a suitable electrical supply and a suitable base are required.
  • What are the electrical requirements for a hot tub or spa?

  • Although some smaller spas may have a reduced electrical requirement, most of our hot tubs require a dedicated 20 amp RCD protected circuit with 30mA trip. Although providing an electricity supply to a hot tub or spa is normally a straightforward task, for safety reasons we recommend that you consult an approved electrician first. Since January 1st 2005 all electrical work must be completed in accordance with IEE wiring regulations and BS 7671. Notifiable work must be either notified directly to the local building control department or completed by an operator who is approved under the Part P Electrical Competent Person Scheme. The electrical cable to the site of the hot tub or spa should be permanently connected or hard wired to the mains supply. Extension cables and any other plug in connections should not be used. At least 5 metres of cable complete with socket should be left at the site of the hot tub or spa to ensure that commissioning is completed satisfactorily.
  • What are the plumbing requirements for a hot tub or spa?

  • No plumbing work is required for any of our hot tubs or spas. You just fill up with a garden hose and top up as required.
  • What is the best surface material to use in hot tubs and spas?

  • Acrylic. All of our hot tubs and most of our smaller spas feature acrylic manufactured by either Lucite or Aristech, the two biggest manufacturers of acrylic in the world. Acrylic hot tub shells retain their glossy appearance even after years of normal use. The surface is hard, non porous, easy to clean and less susceptible to mildew and algae. Acrylic is colourfast so it will not fade even in sunlight. It is also chemical and stain resistant. It is also warm to the touch, which makes it more comfortable for use in a hot tub or spa. Acrylic is also easy to repair because the color goes all the way through and most scratches can be buffed out. It absorbs impacts that damage other materials.
  • How do hot tubs and spas work?

  • Water is drawn through drains in the footwell and through the skim filter. The water is then pumped through a filter, over a heater and then mixed with air before it is returned through the jets. The jets are often adjustable so you can increase or decrease the water flow and air flow from each jet. Our best hot tubs and spas feature unlimited flexibility to suit every taste from the softest touch to a powerful muscle massage.
  • What are the health benefits of hot tubs and spas?

  • For centuries people have enjoyed the relaxation and pain relief offered by natural hot springs. The soothing hydrotherapy provided by a hot tub or spa is a proven relief for stress. Stress is a major problem for our health and general well being. Relief from tension and aching muscles promotes better sleep and relaxation. Submersion in hot water releases natural endorphins to help fight muscle pain and joint pain while at the same time increasing blood flow and relieving the stress on aching muscles and joints. When the body is in warm water blood vessels near the skin relax allowing more blood to flow. The benefits of submersion in warm water continue for some time afterwards. Studies show that soaking for 30 minutes per day benefits certain types of diabetes and reduces the amount of insulin required. Hot tubs and spas also benefit people suffering from arthritis by helping to improve flexibility and easing pain.
  • Can I use my hot tub or spa all year round?

  • Yes, all of our hot tubs and spas are designed to be used in even the coldest weather.
  • How is the water in hot tubs and spas kept clean?

  • Ozone is the most effective sanitation system available for hot tubs and spas. It has been used to treat ground water and surface water in Paris, France since 1906 and in over 2000 other cities around the world. Ozone is also widely used for the treatment of bottled water. It is a powerful oxidiser of most organinc materials including contaminants found in hot tubs and spas such as perspiration and detergents. Combined with chlorine ozone will also oxidise ammonia.
  • How often should I change the water in my hot tub or spa?

  • We recommend that the water is changed every 2 to 4 months depending on the frequency of use. No plumbing is required. The water can be drained away and refilled using a garden hose.
  • How much weekly maintenance will my hot tub or spa require?

  • Stain and scale inhibitor should be added weekly. This prevents the build up of calcium, lime scale and metals which damages hot tubs and spas. Spa clear should be added weekly to keep the water clear. The filter basket should be cleaned at least once a week. The water chemistry should be tested very regularly and at least once a week. The pH balance, alkalinity and chlorine are easy to test using test strips.
  • How much other maintenance will my hot tub or spa require?

  • The filter cartridge should be cleaned every 2 months. The water should be changed every 2 to 4 months depending on the frequency of use. The external surface of the thermal insulated cover should be cleaned regularly and treated with PVC cleaner.
  • How can I reduce the cost of running my hot tub or spa?

  • Use the thermal insulated cover when your hot tub or spa is not in use in order to reduce evaporation and heat loss. Once you have established a comfortable water temperature leave the thermostat at that temperature. Frequent temperatre changes consume more energy. Occasional seasonal temperature changes are recommended partly for your comfort and also to reduce running costs. The temperature should be reduced in the summer and increased in the winter. A sheltered location may result in lower running costs.
  • Can a hot tub or spa be left unused for a long time?

  • Essential maintenance should continue even if your hot tub or spa is not being used. If this is not possible it should be winterized. This is also recommended for any hot tub or spa which is not being used at a location where temperatures below freezing point are likely. To winterize a hot tub or spa first the water is drained away, then the internal plumbing system is drained and then the hot tub or spa is covered.
  • How powerful are the electric motors in my hot tub or spa?

  • It is standard practice throughout the world to inflate the Hp or horsepower rating of consumer electrical goods, including power saws, drills, heaters, generators, pumps and any other equipment with an electric motor. Often the peak power rating is quoted rather than the much lower continuous output rating at which the motor actually operates. The figures are further confused by voltage variations in different countries. The same motor may produce a different output in one country to another. Hot tub and spa equipment is generally made in North America or Scandinavia for a global market. At Summer Garden Buildings the horsepower figures we quote are the lower continuous output rating if known, otherwise if we quote the peak power output it is described as such. The amperage gives a better indication of the power of a motor. Any UK appliance which operates on a 13 amp circuit cannot be more powerful than approximately 2.2 Hp. Any UK appliance which operates on a 32 amp circuit cannot be more powerful than approximately 5.4 Hp. For all of our hot tubs and spas we quote the amperage requirements.
  • Is durawood suitable for use in hot tub cabinets?

  • Yes, durawood is ideal for use in hot tub cabinets. DuraWood is a rigid board made from recycled polyethylene which looks like wood. Durawood even has colour variations just like real wood. However, durawood does not absorb moisture and it will not rot, splinter, or crack. Durawood does not require painting, staining or sealing and it lasts longer than wood. Durawood performs well in extremes of weather. To maintain its smart appearance just clean durawood with soap and water.
  • Is planning permission required for a hot tub or spa?

  • The majority of hot tubs and spas do not require planning permission. However, planning permission may be required for any building in which a hot tub or spa is housed. Planning permission is required for any garden building which covers over half the garden, which is not for domestic use or which is over 3 metres high with a pent roof or 4 metres high with an apex roof. This applies to any garden building including log cabins, gazebos and hot tub enclosures and to any outdoor structure including buildings without walls such as a canopy or a roof only gazebo. Planning permission may also be required for any building which is nearer to a public highway than the original dwelling. For planning purposes a public highway includes any road or footpath with a public right of way. If you live in a Conservation Area or a Listed Building permission may be required for any garden building. This brief summary is not intended to be a comprehensive guide. Contact us for further advice or contact your local planning department. Please note that planning regulations apply to any building whether temporary or permanent including log cabins.
  • Is building regulations approval required for a hot tub or spa?

  • The majority of hot tubs and spas do not require approval under the building regulations. However, approval may be required for any building in which a hot tub or spa is housed. Approval under the building regulations is required for any garden building with an internal floor area of more than 30 square metres including log cabins, gazebos and hot tub enclosures. This applies to any outdoor structure including buildings without walls such as a canopy or a roof only gazebo. Please note that the building regulations apply to any building in excess of 30 square metres whether temporary or permanent.
  • How should I maintain my timber hot tub cabinet?

  • Many of our hot tubs feature a timber cabinet which requires regular treatment. The external timber should be treated with a good quality wood stain every year. This will prolong the life of your hot tub. All major wood stain manufacturers offer suitable products in a choice of colours, available from good hardware shops.
  • What is western red cedar?

  • Western Red Cedar is an attractive timber but it also has an unrivalled reputation for durability. It is ideal for use in the construction of garden buildings and hot tubs. The superior qualities of Western Red Cedar are summed up in this extract from the grading rules published by The Pacific Lumber Inspection Bureau:
  • "The largest and finest of the cedars produced anywhere in the world, the Western red cedar is famed for its extraordinary durability and resistance to decay. Western red cedar is a distinct species, possessing all the desirable qualities of the other cedars, and additional advantages besides. It can be finished to a smooth, silky finish; it is free from pitch, it takes and holds stains and paints excellently, and has superior glueing properties. Its colour is extremely attractive, varying from almost pure white of the narrow sapwood to the light straw shade of dark reddish-brown of the heartwood. The wood of Western red cedar has a vey low coefficient of expansion, so that it does not shrink, swell or warp excessively, even when subjected to changing degrees of temperature and moisture. It has prime insulating qualities and its pleasing aromatic odour is repellent to moths, insects and vermin. The wood is saturated to every fibre with a natural preservative oil which renders it virtually immune to decay and gives it extreme durability without artificial preservative treatment. It is not necessary to paint cedar to preserve its surface, as it does not deteriorate appreciably even under severe climatic changes."

Summer Garden Buildings is a leading UK retailer of hot tubs and spas established in Norwich, Norfolk since 1981.

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