Whole-house water filters
A large filter fitted to the rising main where water enters the property, so every tap, shower and appliance gets treated water.
A whole-house filter — sometimes called point-of-entry — goes in on the incoming main, usually near the stopcock. Everything downstream of it is filtered: the shower, the washing machine, the bathroom taps, all of it.
The usual reason to want one is sediment. Older properties, private supplies and areas with ageing mains can deliver water carrying visible grit, rust or fine particles that block shower heads and wear out appliance valves. A sediment or multi-stage whole-house unit deals with that at source.
It is a bigger commitment than an under-sink filter in every sense: more expensive, physically larger, and it needs cutting into the main. Most households do not need one. Those that do usually know it, because they can see the problem.
Best for
- Visible sediment, grit or rust in the supply
- Private wells and boreholes
- Protecting appliances and pipework across the whole property
- Chlorine removal at every outlet, including showers
- Older properties with ageing internal pipework
Standard on premises with their own supply, and often a prerequisite for downstream RO or softening equipment.
Pros and cons
Pros
- Treats every outlet, including showers and appliances
- Protects downstream equipment from sediment damage
- Large cartridges mean longer intervals between changes
- One system rather than several point-of-use units
Cons
- Needs cutting into the rising main — a real plumbing job
- Takes up meaningful space near the stopcock
- Can reduce flow and pressure if undersized
- Does not soften water unless it is specifically a softener
Can you install it yourself?
Get a plumber for this one
Skill level: Advanced · Time: about 4 hours
This means cutting the incoming main and fitting a bypass. Get it wrong and you are not dealing with a drip under the sink — you are dealing with the full mains pressure of your property with no way to shut it off cleanly. It is also work on the supply pipe, where Water Supply (Water Fittings) Regulations 1999 apply. Use a WaterSafe-approved plumber.
Tools you will need
- Pipe cutter
- Compression or press fittings
- Isolation valves
- Mounting bracket and fixings
Call a plumber if
- Always, in practice
Maintenance
Sediment cartridges every three to six months depending on how dirty the supply is; carbon stages every six to twelve months.
Replacement interval: roughly every 6 months, though volume matters more than time. More on cartridge intervals.
What installation costs
£350–£800 indicative UK labour
Labour only. Varies a great deal with how accessible the stopcock is and whether a bypass loop needs building.
