Proper preparation for delivery and installation is crucial to ensure that your hot tub can be delivered and installed on the agreed date. This preparation involves creating a suitable foundation for your hot tub, verifying that the electrical supply can be connected, and ensuring that the hot tub can be filled with water.
To ensure the safety of your hot tub, it must be placed on a solid and level surface that is capable of supporting the weight of the hot tub, water, and its users. Placing a hot tub on grass or bare ground is not recommended, and we suggest seeking the help of a qualified contractor to create a suitable foundation.
There are several options available for a hot tub foundation, including concrete, paving stones, and decking.
For a concrete foundation, we recommend excavating a 150mm/6inch deep area, laying 50mm/2inches of MOT type 1 sub-base gravel, and filling the area with a minimum of 100mm/4inches of concrete.
Paving stones are a cost-effective solution that offers a variety of sizes, shapes, and finishes. For a paving stone foundation, we advise excavating an approximately 130mm/5inch area, laying 50mm/2inches of MOT type 1 sub-base gravel, and then laying 25mm/1inch of dry mix/cement sand on top of the MOT gravel. Bed the chosen patio slabs/stones into the compacted cement sand.
Decking can also be used as a base for a hot tub, but it is important to consult with a qualified professional to ensure that the decking can support the weight of the hot tub. For a minimum decking base, support joists should be a maximum distance of 200mm/8inches apart.
Crushed Stone / Gravel
A crushed stone or gravel base can also be used, especially for smaller hot tubs. The area should be levelled and compacted, and a weed barrier installed before adding the stone or gravel.
If you are installing the hot tub indoors, a concrete or tile floor may be suitable, but you may need to reinforce the floor if it is not already designed to support heavy loads.
It is recommended to consult with a licensed contractor or engineer to determine the appropriate foundation for your specific hot tub and location.
It is important to ensure that your hot tub is connected to the correct electricity supply to prevent any accidents or electrical faults.
The standard heater is 32AMP – a 6mm² 3-core SWA cable is required.
If being supplied with the auxiliary heater then a 10mm² 3-core SWA cable is recommended.
In addition, an IP65 45AMP Rotary Isolator Switch is also necessary to isolate the hot tub during an emergency or service work.
It is important to ensure that the isolator switch is sited at least 2 metres away from the hot tub to prevent bathers from touching it. The electrician should fit a suitable weatherproof block connector to the end of the tail from the isolator, and waterproof gland packs should be used to prevent water ingress on all electrical connections. Earth cables should also be clearly colour coded with green/yellow insulating tape or earth sleeve.
The electrical installation must comply with BS:7671 – “Requirements for electrical Installations IET Wiring Regulations,” particularly concerning the hot tub’s maximum amperage pull. The hot tub must be hard wired on its own fused spur back to the household consumer unit, not sharing a supply with any other appliances. It should also be protected by a sufficiently rated MCB and an RCD.
Outdoor cabling should be protected from damage by either laying protective ducting (pc pipe) below ground or by using Steel Wired Armoured (SWA) cable. It is recommended to seek professional advice from a fully qualified electrician if in doubt about the required electrical guidelines.
It is advised that your electrician leaves enough spare cable attached to the isolator to reach the furthest side of the hot tub, usually a minimum of around 7m to 8m. If the isolator is located further away, a longer length of cable should be used.
To fill a hot tub, a substantial amount of water is required. Therefore, a mains water supply and a sufficiently long hosepipe to reach the hot tub from the supply are essential for a smooth and efficient installation process.