How to Install Outdoor Spa, Hot Tub or Jacuzzi

Install Outdoor Spa DIY

Confused about how to install an outdoor spa or Jacuzzi in your backyard? Well, read on.

Outdoor Spas, Hot tubs, or jacuzzis are a great way to unwind and recuperate after a hard day at work or a sports injury. If you are going to invest a lot of money in an outdoor spa there are a few simple things to think about before going ahead with your purchase. If you want to Install your spa yourself read on to see how easy it can be to save a heap of money.

What type of Spa do you need?

There are endless types and models of outdoor spas out there at the moment. Your first decision is who many people will use it at the same time.

  • Do you need a 2-person or a 7-person?
  • Massage, do you need Hydrotherapy or just a relaxing bubble machine?
  • What about the Entertainment home theatre setup? Do you need lights and sound? (speaker system spa)
  • Seating, do you need a lounge or just seats in your outdoor spa?
  • How big would you like your spa to be?
  • What color of the Spa or Hot tub?
  • Do you want an advanced electrical spa controller? Eg would you like to be able to control your spa via your mobile phone.
  • How many electrical amps will the spa use? This will determine if you need to put in another circuit.
  • Price range
  • Are you buying a Chinese, American, or Australian-made spa?

How to Install Outdoor Spa, Jacuzzi or Hot Tub

Delivery of your Jacuzzi or Outdoor Spa is best left to the professionals. They can be very heavy. We went with an Oasis Riveria Spa in Stirling marble with Mocha cabinet colors.

The Rivera is a large, luxurious open-plan spa with different seating styles – perfect for socializing as well as those looking for a serious hydro-massage experience. But large means heavy get a few guys to help you position the spa into place.

Spa Location

Crane lifting spa Hot tub

Most of the time you should be able to fit the spa of your choice somewhere on your property. The spa shop will be able to tell you how the delivery people will handle your spa. Usually, it’s by a trolley and a few guys, as most 6 or 7-person spas, should be around 400kg or less.

The  Outdoor spa will be tipped on its side and pushed along on rollers to its final resting place. Be aware of the width of the spa as this will be the height when put on its edge for transport. Sometimes you can ask for a crane for hard-to-reach spots which may incur some extra costs.

If the spa location is on sloping ground you will have to level it before laying a concrete slab or pavers.

Spa Slab Base

The base of your spa must be perfectly level and firm to stop the spa from being at an angle and possibly moving and cracking. If the spa isn’t supported on all 4 corners it may have some structural cracking and cause leaking of the spa.

To solve this problem most people will either lay 40mm pavers or lay a 90-100mm concrete slab.

Both have pros and cons, but the cheapest is laying the pavers. A concrete slab will be more stable and will last a very long time if done correctly. I chose to lay a concrete slab for my new spa.

How to Prepare a Concrete Slab for your Spa

Spa slab concrete base
  • 1st step is to peg out the square size of your slab. Go 100mm longer and wider to give yourself some room. Dig out the vegetation and topsoil. This will stop voids from becoming present once the cement hardens and the vegetation rots away.
  • Next level out the ground the best you can but don’t get too fussy as we will fix it on the next step.
  • Cut out your concrete formwork and screw or nail it together. This will be the slab base, now is the time to level your formwork. Use a spirit level and sand, to pack under the formwork on each side and corner.
  • Once it’s all level, use wooden or metal stays to peg in your formwork to stop it from moving. You will need about 2 per side. Hammer these into the ground, and screw to your formwork on the outside.
  • Run any conduit and electrical cables you may need for your outdoor spa. 10amp spas can get away with 2.5mm cable, whereas 32amp spas will need 6mm cable. Both will also need an ELCB (Earth Leakage Circuit Breaker)
  • Lay down Builders Plastic or Polythene Film to act as a moisture barrier for your base. This will stop any rising damp.
  • Put down some Bar Chairs, these hold the reo bar grid mesh in place and off the ground. These are cheap at around $10 for a whole heap. Space them every 500mm.
  • Drop down the reo mesh and tie it together if using small mesh panels. Cut to fit using bolt cutters or an angle grinder. Dont forget to earth the reo mesh as it’s in a pool zone.

It’s now time for the Wet Concrete…..

How to Pour a Concrete Slab

The two ways you can do this. You can mix your own concrete from 20kg bags or get in a minimix cement truck.

To work out how much cement you need use some maths and times the Length by the width by the depth in meters

So my slab framework size is 2.7m x 2.7m x 0.090m deep = 0.65m³

I ordered 0.7m³ of concrete to allow for any over carry or spillage. Basic cement is fine or 20mpa or less. There are a few different types of cement-like GP (General Purpose), GB (General Blended). Just get whatever is cheaper, there is no need to upgrade strength or type for just a basic shed/spa cement slab.

Make sure you have a few helpers on the day and a good strong wheel barrow or two. The cheap garden wheel burrows won’t be up to the task to hold 80kg plus of concrete cement.

Pour the concrete into the framework and use a shovel to work out all low/high spots. It’s now time to screed off and make it level. I used a bull float that I made myself and it was the best. So easy to use.

Best to show you how to screed cement, so Thanks to iCreatables.

You can mount the Spa onto the slab after about one week. Complete the wire-up using an electrician to check all your work and sign off.

How to Wire Up a Spa Hot Tub.

Wire up spa sv3

Depending on the type of spa you buy, there are basically 2 types of electrical connections.

The 15amp plug-in spa, is a very basic usually smaller spa that will plug into a general-purpose 15 amp outlet.

The 32 amp hard-wired spa. Larger spas with 2 pumps or more and larger heaters.

The 15 amp spa is the easiest to wire up. Run new 2 core and earth cable to a 15 amp outlet and plug-in the spa.

32 amp spas are a lot more involved. You will have to take into account a few items like – Cable run length, above-ground or beneath-ground cable run, conduit size, and maximum demand/voltage drop.

Spanet sv3 wire up 6mm sv4

I chose to go with a 6mm 2 core + Earth tps electrical cable inside 25mm conduit. This was run inside the roof space down a wall to an isolation switch and then underground to the spa.

Inside the spa, I used a flexible 25mm conduit all the way to the Spanet sv3 controller. The Spanet sv3 only has 20mm gland holes so I drilled out a larger 25mm hole to suit the conduit.

Cable tie the flexible conduit inside the spa to stop it from vibrating around.

Don’t forget to earth the slab Reo. Also, earth any metal that is within 2m of your spa. I used 6mm earth cable wire.

Spa pre-startup inspection.

Check over all of the plumbing and electrical work twice before starting to fill your hot tub.

Fill your spa up with water through the filters. This will make sure all hoses and pumps get primed with water. Keep all your spa side panels off at this stage.

Oasis spa night

Once your spa is full check for leaks. Turn on your spa circuit breaker and isolation switch. Program your spa controller. The 2 most popular controllers are Spanet and Balboa.

Start each spa, Hot tub pumps, and blowers. Check for leaks again. You can fix leaking Jacuzzi jet pumps and fittings yourself.

Put In your chemicals like lithium sanitizes and test your pH level.

Job done, Install your top cover and wait a few hours for your spa to heat up. Its also best while you are waiting to protect your spa cover with a UV-stabilized product. You can check out our review on the 303 vinyl spa cover protectant.

Spa Cover Lifter

Trust me you will want a spa cover lifter.

DIY Spa cover lifter Oasis jacuzzi

As our Oasis spa is quite large the insulation top cover is also large and heavy. I recommend buying or making a spa cover lifter otherwise it’s a 2 person’s job to take it off and put the cover lifter back on.

DIY Home made spa cover lifter metal pipe open

I ended up making a Spa Cover Lifter for this hot tub which works out great for about $50. The shop version was around $400

Oasis Riviera Pro Spa Specs

  • Seats 8 – But you could fit 10 kids in there
  • Total Massage Jets – up to 73
  • Aqua Stream Jets – up to 56
  • Air Jets – up to 18
  • 1 x Volcano Jet
  • 2 or 3 3HP High-Performance Massage Pumps – These rock so much power
  • .5HP Filter Pump. Mine came with a 0.25hp pump so saves more money when filtering
  • 1 x Variable Blower Air Pump
  • 1 x Recliner Lounge
  • Foot Massage in up to 3 Seats
  • 1 x Neck & Shoulder Therapy Seat
  • Adjustable Liquid Aromatherapy System – Smells great
  • Huge 5 Inch Multi-coloured Underwater LED Light
  • Water Level LED Lights – Changing colors
  • LED Backlit Waterfall – Roman waterfall
  • LED Backlit Spa Controls – SpaNet
  • Easy Care Water Treatment System – Ozonator
  • 8 Layer Power Saver Insulation System – So much insulation it’s fantastic.
  • Solid Fibreglass “Weather Barrier” Base – Keeps the vermin out
  • 6Kw Variable Output Teflon Coated Heater – one of the largest heaters around
  • Stainless Steel Jets Trims
  • Lockable Hard Cover – Keeps those kids out of the spa.
  • Maintenance Free Cabinet UV treated synthetic material specifically designed for harsh Australian conditions.

How Much Money is a 6-Person Spa in Australia

Well depending on jets, pumps, and features the sky is the limit. Never pay retail, always haggle. The markup on spas is huge. We visit most of the spa dealers around us and each time while talking price they were able to come down a few thousand dollars.

The Oasis Riviera is around the $11000 AUD mark depending on the Pro or the Hydro and if delivery is included or not.

Enjoy. Let me know how below what brand of spa you have and what you like about it.

How much electricity does a hot tub spa use?

Our spa has a 6kw heating element and we only run it for around 1-2 hours a day. We have set up the timer to heat the hot tub at midday to maximize our solar panel electricity generation as the feedback into the grid only pays us a few cents per KW so it is better to use it ourselves.

This way we pay less for electricity per day.

Another way if you don’t have solar panels is to plan your heating up during the off-peak times often that is after midnight.

Most hot tubs need around 1-2 hours of heating and 2 hours of filtration per day. So expect to add around 8-14kw of electricity per day to your electricity usage account.

This is dependent on outside temperature eg summer or winter.

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