An infinity swimming pool is designed so that water flows over one or more edges, creating the illusion that the pool disappears into the horizon. The effect is particularly impressive when the pool overlooks the sea, a harbour, hills or another unobstructed view.
But there is considerably more going on behind that disappearing edge than you might realise. An infinity pool needs additional water-handling equipment, careful hydraulic design and extremely accurate construction. On the right property, the result can be spectacular. On the wrong property, you can spend a lot more money without getting much of the visual benefit.
If you’re considering an infinity pool in New Zealand, here’s what you need to know before committing to the design.
What is an infinity swimming pool?
An infinity pool, also called a vanishing edge pool, negative edge pool or sometimes an eternity pool, is a swimming pool where water flows continuously over one or more edges into a lower catch basin.
From the swimming area, you generally can’t see the basin. Instead, the overflowing water makes the edge appear to disappear into the landscape.
The basic system works like this:
- Water circulates through the swimming pool as normal.
- Water reaches the infinity edge and flows over the precisely levelled lip.
- The water falls into a catch basin below.
- A separate circulation system returns the collected water to the main pool.
- The cycle continues while the infinity feature is operating.
The illusion is simple. The engineering isn’t.
The effect works particularly well on properties with a significant change in elevation. A hillside section overlooking Auckland’s harbour, for example, can make an infinity edge look as though the pool runs directly into the water beyond it.
On a flat section, however, the effect can be much less impressive.
How does an infinity pool work?
The most important component that separates an infinity pool from a conventional swimming pool is the overflow and catch-basin system.
A conventional pool normally has a skimmer or overflow system that removes water from the surface for filtration and circulation. An infinity pool deliberately sends water over its edge.
The infinity edge
The edge has to be extremely level.
If one section is even slightly higher than another, water will preferentially flow over the lower section. That can produce an uneven sheet of water rather than the smooth, uniform overflow you’re paying for.
This is why the construction quality around the infinity edge matters so much.
The finished edge, coping and surrounding structure also need to tolerate New Zealand’s weather conditions, including strong sunlight, rain, wind and, in coastal areas, salt exposure.
The catch basin
Below the infinity edge is a basin designed to collect the water.
The basin needs enough capacity to cope with changes in water level caused by people entering the pool, splashing, rainfall and other conditions. It also needs a suitable pump and pipework to return the water to the swimming pool.
This is one of the areas where an infinity pool becomes more complicated than a conventional pool.
A poorly designed catch basin or return system can cause problems with water levels, pump operation and overflow performance.
Additional pumps and pipework
Depending on the design, an infinity pool can require additional circulation equipment compared with a conventional pool.
The catch basin needs to be emptied back into the main pool at an appropriate rate, while the main pool still needs normal filtration and circulation.
This means the hydraulic design needs to be considered during the initial pool design, rather than trying to add the infinity system later.
Why are infinity pools so popular?
The main attraction is obvious: the view.
An infinity edge can visually connect the pool with the landscape beyond it in a way that a conventional pool can’t.
They’re particularly effective when the pool is positioned above:
- The ocean
- A harbour
- A lake
- A valley
- Rolling countryside
- A large garden
- A city skyline
The pool becomes part of the surrounding landscape rather than simply sitting in the backyard.
This is why you’ll often see infinity pools associated with resorts and luxury homes. The design works best when the property itself provides something worth looking at.
What to know before installing an infinity pool
Before you get too attached to the idea, look carefully at the site.
The most important question isn’t actually, “Can an infinity pool be built here?”
It’s:
“What will I see beyond the infinity edge?”
If the answer is a spectacular view, the design could be a great choice.
If you’ll be looking straight at a boundary fence, neighbouring house or retaining wall, the expensive infinity mechanism may not add much.
1. Your site needs to suit the design
Sloping properties are particularly suitable because the catch basin can be positioned below the pool while remaining relatively unobtrusive.
A flat property can still potentially have an infinity edge, but the builder needs to create the necessary difference in levels artificially.
That can add considerably to the construction complexity.
2. Think about the catch basin
Don’t concentrate entirely on the visible pool.
Ask the builder where the catch basin will go and how it will be accessed.
You’ll eventually need to:
- Inspect it
- Clean it
- Service the pump
- Deal with leaves and debris
- Check water levels
- Access plumbing and equipment
A catch basin hidden in an awkward location can become a maintenance headache.
3. Consider wind exposure
This is particularly relevant to exposed Auckland, Wellington and coastal properties.
Wind can blow water away from the infinity edge, increase evaporation and carry leaves and debris into the catch basin.
A pool with a beautiful exposed view may therefore have a different maintenance profile from a sheltered backyard pool.
4. Think about what happens when the pool isn’t running
The infinity effect depends on water flowing over the edge.
When the system isn’t operating, the visual appearance can be different.
Ask the designer what the pool and edge will look like when the infinity system is switched off for maintenance or when equipment isn’t operating.
Infinity pool advantages and disadvantages
| Feature | Advantages | Disadvantages |
|---|---|---|
| Appearance | Exceptional visual effect | Only worthwhile if the site suits it |
| Views | Can visually merge the pool with the landscape | A poor view can make the feature pointless |
| Design | Can be highly customised | More complicated than a standard pool |
| Water circulation | Continuous overflow can help remove surface water | Requires additional hydraulic design |
| Maintenance | Modern equipment can automate much of the system | More equipment means more components to maintain |
| Cost | Creates a premium architectural feature | Usually considerably more expensive |
| Sloping sites | Can make excellent use of difficult terrain | Structural engineering may be required |
| Running costs | Can be managed efficiently with appropriate equipment | Overflow and additional pumping can increase energy and water use |
The big takeaway is that an infinity pool isn’t automatically better than a conventional pool.
It’s better when the site makes the infinity effect worthwhile.
Are infinity pools more expensive?
Yes. An infinity pool will generally cost more than a comparable conventional pool because you’re paying for additional structural and hydraulic work.
The extra cost can come from:
- The catch basin
- Additional pipework
- Pumps and controls
- Structural engineering
- Retaining structures
- More complicated excavation
- Precision construction of the overflow edge
- Additional waterproofing
- Premium finishes
- More complicated electrical work
- Difficult site access
There isn’t a reliable single New Zealand price because site conditions make a huge difference.
As an indication, one Auckland infinity-pool builder currently publishes example 8 m x 4 m infinity pool construction costs of approximately $123,000 to $175,000, with larger 10 m x 5 m examples at approximately $165,000 to $233,000. These are builder-published figures rather than a national price guide, so they shouldn’t be treated as a quote.
Another Auckland industry source currently estimates roughly $130,000 to $190,000 for an 8 m x 4 m infinity concrete pool before GST and earthworks, with more complex projects potentially reaching considerably higher.
The important point is that the site can matter as much as the pool itself.
A difficult hillside excavation, restricted access, retaining requirements or significant structural engineering can quickly change the budget.
When comparing quotes, make sure you know whether the price includes the catch basin, pumps, engineering, earthworks, electrical work, finishes, fencing and consenting.
Infinity pool maintenance
An infinity pool isn’t necessarily difficult to maintain, but there are more components to understand.
The swimming pool itself still needs normal maintenance, including:
- Regular water testing
- Correct chlorine levels
- pH management
- Filter cleaning
- Pump maintenance
- Skimming and cleaning
- Brushing
- Equipment inspections
The infinity system adds another area to keep an eye on.
Keep an eye on water levels
Water can be lost through evaporation, splashing and wind, just as it can with any pool.
With an infinity pool, the catch basin and main pool need to remain at appropriate operating levels.
A significant loss of water can affect how the overflow system operates.
An automatic top-up system can make life considerably easier, but it should still be monitored rather than treated as something you can forget about.
Keep the catch basin clean
Leaves, dirt and other debris can end up in the catch basin.
Depending on the design, there may be strainers or other filtration components protecting the return pump.
Don’t ignore these.
A blocked intake or poorly maintained catch basin can affect water circulation and potentially cause equipment problems.
Watch your water chemistry
The overflow system doesn’t eliminate the need for proper water chemistry.
If anything, it’s particularly important to maintain good circulation and filtration because the pool has additional plumbing and equipment involved in moving the water.
If you’re using a salt chlorinator, the system needs to be properly designed around the pool’s circulation and water volume. The manufacturer’s installation and operating requirements should always take priority.
Does an infinity pool use more water?
It can.
The water flowing over the edge isn’t necessarily “lost” because it is collected and returned to the pool.
The real losses come from things such as:
- Evaporation
- Wind
- Splashing
- Rainfall events that cause water to overflow
- Water removed during maintenance
An exposed infinity edge can increase evaporation compared with a conventional pool, particularly when wind is blowing across the water.
This is another reason a properly designed automatic top-up system and an appropriate pool cover can be worthwhile.
What type of pool is best for an infinity design?
Concrete infinity pools
Concrete is a common choice for custom infinity pools because the structure and overflow edge can be designed specifically for the site.
You aren’t limited to a particular manufactured shape, which is useful when you’re trying to position the edge precisely against a view.
The downside is that custom concrete construction is generally more involved and expensive.
Fibreglass infinity pools
Infinity-edge fibreglass systems are available, but they’re less straightforward than a standard fibreglass pool.
The overflow edge needs to be accurately positioned and level, and the catch basin and hydraulic system still have to be designed.
Some manufacturers offer engineered systems specifically for elevated or infinity applications, so this isn’t necessarily a concrete-only proposition. However, your choice should be based on the particular system, site and installer rather than assuming one material is always superior.
Infinity pool safety and New Zealand regulations
An infinity edge doesn’t remove your obligations under New Zealand pool safety requirements.
Under Building Code clause F9 and the Building Act 2004, residential pools that are filled or partly filled with water must have physical barriers that restrict unsupervised access by children under five. The requirements apply to residential pools that can be filled to a depth of 400 mm or more.
This is particularly important with an infinity pool because the surrounding landscape can be complicated.
A retaining wall, deck, balcony, stairs or other structure around an elevated pool can potentially affect how the pool barrier works.
Don’t assume that because the infinity edge is high above the ground, the pool automatically meets the requirements.
MBIE’s F9/AS1 provides an acceptable solution for residential pool barriers. For example, barriers not located on a property boundary generally need to be at least 1,200 mm high from the finished ground or floor level outside the barrier, with additional requirements concerning openings, climbing features and construction.
Residential pool barriers are also subject to periodic inspection. The Building Act requires qualifying residential pools to be inspected at least once every three years to check that the barriers comply.
Does an infinity pool require building consent?
Pool construction generally requires building consent unless the particular work falls within an exemption under Schedule 1 of the Building Act. Even where the pool construction itself is exempt, the pool barrier is subject to its own requirements.
For an infinity pool, you should discuss consenting with your pool designer, builder and council before construction begins.
This is especially important on sloping or elevated sites where structural, earthworks and site-specific issues can make the project more complicated.
Don’t rely on a generic statement that “pools don’t need consent”. The circumstances of the particular project matter.
Common mistakes people make with infinity pools
Choosing the design before assessing the view
This is probably the biggest mistake.
An infinity edge isn’t impressive simply because water flows over it.
The surrounding view is what creates the magic.
Stand where the finished edge will be and look outward before committing to the design.
Underestimating the engineering
The visible part of an infinity pool looks simple. The structure underneath may not be.
This is particularly true on steep Auckland sections or properties with significant retaining requirements.
Make sure structural engineering and site requirements are properly considered before construction starts.
Forgetting about equipment access
Don’t hide pumps, valves and catch basins somewhere that will be difficult to access later.
Pool equipment eventually needs servicing. Make sure there’s enough room for a technician to work comfortably.
Comparing quotes on pool size alone
Two pools with identical dimensions can have dramatically different costs.
Compare what is actually included in each quote.
Pay particular attention to:
- Catch basin construction
- Pumps
- Pipework
- Structural engineering
- Excavation
- Retaining structures
- Electrical work
- Pool finish
- Coping
- Pool fencing
- Consent fees
- Landscaping
Treating the infinity system as maintenance-free
It isn’t.
The system can be automated, but pumps, strainers, sensors, plumbing and the catch basin still need attention.
When to call a professional
There’s plenty of normal pool maintenance you can handle yourself, including testing your water, cleaning the pool and carrying out routine checks.
An infinity pool becomes a different proposition when structural or hydraulic work is involved.
Get appropriately qualified professionals involved for:
- Structural design
- Major excavation
- Retaining structures
- Pool construction
- Electrical work
- Complex plumbing
- Pump and hydraulic design
- Building consent questions
- Pool barrier compliance
- Major leaks or structural problems
I’d be particularly cautious about trying to modify an infinity edge yourself. The entire visual effect depends on precise levels and water flow, and mistakes can be expensive to fix.
Is an infinity pool worth it?
For the right property, absolutely.
If you have an elevated site with a genuinely impressive view, an infinity swimming pool can be one of the most effective ways to make the pool part of the landscape.
But don’t choose one simply because infinity pools look great in photographs.
The design makes the most sense when you have:
- A strong view beyond the pool
- Suitable site elevation
- Enough room for the catch basin and equipment
- A realistic construction budget
- Appropriate structural design
- Good access for maintenance
- A plan for compliant pool barriers
If your property is flat and the infinity edge will simply look towards a fence or neighbouring property, I’d seriously consider spending the additional money on a high-quality conventional pool instead.
The best infinity pool isn’t necessarily the biggest or most expensive one. It’s the one where the site, view, structure and water system all work together.
Frequently Asked Questions
What is the infinity pool meaning?
An infinity pool is a swimming pool designed with one or more edges where water continuously flows over into a concealed catch basin. From the pool, the edge appears to disappear into the surrounding landscape.
What is another name for an infinity pool?
Infinity pools are also commonly called vanishing edge, negative edge or infinity-edge pools. Eternity pool is another term sometimes used to describe the same general visual concept, although terminology varies between builders and markets.
Can you build an infinity pool anywhere in New Zealand?
Technically, infinity-edge systems can be designed for many different sites, but they’re much better suited to properties where the edge has a meaningful view beyond it. Sloping sites are particularly well suited because the catch basin can be positioned below the main pool.
Are infinity pools more expensive to maintain?
They can be. The pool still requires the same basic water care as a conventional pool, but the infinity system adds equipment, plumbing and a catch basin. Wind and evaporation can also increase water loss on exposed sites.
How much does an infinity pool cost in New Zealand?
There is no reliable nationwide price because site conditions have a huge influence on the final cost. Current Auckland builder-published examples put medium-sized infinity pools well into six figures, with difficult sites potentially costing substantially more. Treat published figures as indicative only and get a site-specific quote.
Are infinity pools legal in New Zealand?
Yes. Infinity pools are not prohibited, but like other residential pools, they must meet applicable New Zealand Building Code and pool safety requirements. Pool barriers are particularly important, and qualifying residential pools are subject to periodic inspections.
The bottom line
An infinity swimming pool is much more than a normal pool with water spilling over one side. The catch basin, pumps, plumbing, structural design and precision overflow edge all have to work together to create the effect.
For a New Zealand property with a spectacular harbour, ocean, valley or hillside view, it can be an exceptional pool design.
But the site should come first and the infinity feature second. Look at the view, understand the engineering, investigate the consenting and barrier requirements, and make sure you understand the ongoing maintenance before signing a contract.
If the infinity edge genuinely improves the relationship between your pool and the landscape, the additional complexity can be well worth it. If it doesn’t, a well-designed conventional pool may give you a better result for considerably less money.
