Whole-house filter and reverse osmosis, Clovelly

This Clovelly family first called Norton Plumbing about a leak. Once it was fixed, we left a water filtration brochure on the bench. Some time later they rang back with the brochure in hand. They wanted two things: filtered water at every tap in the house, including the showers, and the best drinking water they could get at the kitchen sink.

One filter can't do both jobs well. So Adam and Greg fitted a Puretec FilterWall F5 on the mains in the front yard, and a Puretec RO270 reverse osmosis system under the kitchen sink. This post covers why the two are paired and what the install involved.

Whole-house filter vs reverse osmosis: what each one does

A whole-house water filter sits on the mains where the water enters the property. Everything after it is filtered: showers, basins, the laundry, the garden tap and the kitchen. The FilterWall is a three-stage system: a washable sediment cartridge, a finer sediment cartridge, then a carbon block. On Puretec's specification it reduces chlorine by up to 98%, along with sediment, and Puretec list the F5 among their systems for reducing PFAS.

Reverse osmosis works differently. It pushes water through a very fine membrane that holds back far smaller particles than a carbon cartridge can. It's slower and only makes sense at one tap, so it goes under the kitchen sink for drinking and cooking water.

Puretec describe a whole-house FilterWall paired with under-sink reverse osmosis as their most thorough setup for reducing PFAS. That pairing is what went into this house.

Installing the FilterWall in a Clovelly front yard

Most FilterWalls we install go down a side passage or against a back fence. At this house the water meter sits in the front garden behind a rendered wall with a sandstone coping, which is a common layout on Clovelly's sloping streets. The cabinet went on that wall, right beside the meter, so the run from the main is short and nothing in the garden had to be dug up beyond the pipe trench.

Here's what the whole-house install involved:

• Mounted the FilterWall cabinet on the front wall beside the meter, on timber packers so it sits square on the render.
• Cut into the incoming copper after the meter and ran it up into the cabinet and back out to the house.
• Fitted the three cartridges and closed up the cabinet.
• Commissioned and tested, checked every joint, then ran water through to the taps.

The reverse osmosis system under the kitchen sink

Under the sink, the Puretec RO270 was fitted to the cold supply with its own dedicated drinking tap on the bench, so the main kitchen mixer stays as it was. Because the water reaching it has already been through the FilterWall, the reverse osmosis pre-filters do less work, which is one practical reason to pair the two.

Two things worth knowing if you're considering reverse osmosis:

• It sends some water to drain. That's how the membrane keeps itself clean. It's normal, and it's one reason reverse osmosis goes on the drinking tap rather than the whole house.
• It needs cupboard space. Most under-sink reverse osmosis systems have a small storage tank as well as the filter housings. Check your sink cupboard before you set your heart on one.

Signs a whole-house filter plus reverse osmosis suits your home

Not every house needs both. In our experience, the pairing makes sense when:

• You want filtered water in the shower as well as the kitchen, not just a jug in the fridge.
• You're still buying bottled water because you don't trust the tap.
• PFAS is the worry. A whole-house filter alone reduces it. Adding reverse osmosis on the drinking tap is Puretec's recommended step further.
• You're renovating the kitchen anyway, so the cupboard space and a drinking tap can be planned in.

If you only want better drinking water, an under-sink filter on its own may be enough. The Coogee under-sink case study covers that option. You can also look up the tested quality of your own area's water on Sydney Water's water analysis page.

How to reach Norton Plumbing

Norton Plumbing is a family-owned Eastern Suburbs plumbing business and a Puretec Specialist Plumber. Adam Norton holds NSW plumbing licence 397768C and does the filtration assessments himself. Call 0477 858 951 to book a free visit. We'll look at where your main runs, what space you have under the sink and which setup suits the house. See our water filtration page for whole-house and under-sink options side by side, or our Clovelly plumber page for everything else we do locally.