Why people go whole-house instead of under-sink
An under-sink filter fixes the water you drink. That is usually enough, and we say so.
Whole-house is what people choose when the problem is not the drinking water. It is the smell when the shower first runs. It is filtered water being available at exactly one tap while the other eight in the house are not. It is having put an under-sink unit in two years ago and finding it solved a smaller share of the annoyance than expected.
It is also the only one of the systems that does anything about the water you wash in, which for a lot of households is the actual reason they started looking. Compare all four systems
Where the unit goes in a Kardinya house
At the point the water comes into the property. That is the constraint, and it is not negotiable — anything upstream of the filter is unfiltered, so the filter goes first.
In practice that means near the meter at the front boundary, or on the incoming line where it comes up at the house, usually down a side boundary. Kardinya is a detached-housing suburb — at the 2021 Census, 2,978 of its dwellings were separate houses, 86.1 per cent of occupied private dwellings — and a detached house on its own block with side access is close to the easiest arrangement this job can have.
There are still things to work out on the day, and they are the same things everywhere:
Is there physical room?
A whole-house unit is not one small canister. It is a housing or a bank of housings on a bracket, with clearance underneath, because the bowls have to come down to change a cartridge. A tight side passage against a fence changes what will fit.
Is it protected?
Housings sitting in full Perth sun year-round are not doing themselves any favours. There is usually a better spot a metre away.
Can you get at it?
Someone has to service this thing. Behind the bins, under a deck or at the back of a locked side gate is a decision you regret in eighteen months.
Does the house keep water while it is serviced?
It should. A bypass built in at installation means a cartridge change does not mean shutting the whole house off. This is the part that separates a proper install from a cheap one, and it should be on the quote.
Why this one legally needs a licensed plumber
A whole-house filter is cut into the incoming water main. That is plumbing work on the drinking water supply, and in Western Australia it is done by someone holding a licence — not by whoever is handy with a pipe cutter.
There is a practical reason as well as a legal one. The join is on the line feeding the entire house, at mains pressure, usually outdoors and often out of sight. A fitting that weeps at an under-sink unit gets noticed in a day because it is in a cupboard you open. The same fitting weeping on a side boundary can run for months.
Plumbing Licence 8396, held by Tim, who does the work himself. The person who quotes the job is the person who fits it.
How the job runs
1. You ring or send the form
Tell us roughly where the meter is and whether there is side access.
2. A licensed plumber comes out at no charge
He looks at where the main enters, what the pipework at that point is made of, and where a unit can actually be mounted and reached.
3. You get a written price on site
Itemised, before anything is touched. Transparent pricing, no hidden costs. If you would rather think about it, think about it — there is no follow-up campaign.
4. We fit it
Water isolated, the line cut in, housings mounted on a bracket, bypass arrangement built in, unions so it can be serviced later.
5. Flushed and tested
New carbon cartridges have to be run through before the water is worth drinking, and the whole thing is checked under pressure before we leave.
6. Paperwork
The manufacturer's documents for the unit, and a straight answer about when the cartridges are next due.
What it costs
The unit you choose, how many stages it has, where the main enters the property, whether there is room to mount housings and a bypass, and what the existing pipework at that point is made of and what condition it is in.
That last one is the reason this page does not carry a number. A house built between 1967 and the 1980s — which covers most of Kardinya — has had fittings changed by several different hands over the decades, and what is at the incoming main now is not always what the plans said. A licensed plumber looks at it and you get the real figure in writing, before anything starts.
Afterwards
Cartridges are consumable. Manufacturers generally nominate a period, commonly around twelve months, and how much water the household uses moves it either way. The signs you will actually notice are flow dropping off and the taste starting to come back.
When that happens it is a service, not a new system. Cartridge replacement in Kardinya