Is Whole-Home Water Filtration Right for Your Home?
Start by knowing your water. How to choose between whole-home and point-of-use filtration.
Maor Greenberg
A whole-home filter, also called a point-of-entry system, treats water where it enters the house, so every tap, shower and appliance gets filtered water. Whether you need one depends on what is in your water and what you want to change. The right first step is not buying a filter, it’s knowing your water.
The CDC’s advice is simple: test your water, then choose a filter that removes the specific germs or chemicals you’re concerned about. If your water has nothing harmful in it, you may not need a filter at all.
Step 1: Know your water
- On city water: read the annual water quality report your utility must publish. It lists what was found and at what levels.
- On a private well: test at least once a year, through a state-certified lab.
- In an older home: the water can pick up metals or sediment from the house’s own pipes after it leaves the street. Related: Asbestos and lead in 1950s homes.
Step 2: Decide what you want filtered, and where
Whole-home (point of entry)
- Where it sits: at the main water line.
- What it treats: every tap, shower and appliance.
- Good for: sediment, taste and odor throughout the house, and water for bathing.
- Watch out for: filters that remove disinfectant can let germs grow in the pipes after the filter.
Point of use
- Where it sits: under one sink or on one faucet.
- What it treats: drinking and cooking water at that tap.
- Good for: drinking water, including contaminants picked up from the home’s own plumbing.
- Watch out for: it only treats one location.
Many homes combine the two: a whole-home filter for sediment, taste and odor, plus an under-sink system, such as reverse osmosis, at the kitchen for drinking water.
Step 3: Choose a certified system
The CDC recommends checking a filter’s NSF certification, which shows what it is tested to reduce. Common standards include:
- NSF/ANSI 42: taste and odor, such as chlorine taste.
- NSF/ANSI 53: health-related contaminants, such as lead and cysts.
- NSF/ANSI 58: reverse osmosis systems.
Always check the specific product’s listing. Two filters certified to the same standard can be certified for different contaminants.
An important caution
City water contains chlorine or chloramine on purpose, to keep germs from growing in the pipes. The CDC notes that a whole-home filter that removes disinfectant can allow more germs to grow in your plumbing after the filter. A good design accounts for that, and every filter needs its cartridges changed on schedule.
Why a remodel is the right time
During a remodel or rebuild, a whole-home system can be planned into the plumbing from the start, with space for the unit, easy access for filter changes, and new supply lines throughout. Replacing old galvanized pipes at the same time removes a common source of rust and sediment.
FAQ
Do I need a whole-home filter if I’m on city water?
Not necessarily. Read your utility’s water quality report first. Many homeowners choose one mainly for taste, odor and sediment.
Will a whole-home filter remove lead?
It depends on the product and where the lead comes from. If lead comes from your home’s own plumbing, a point-of-use filter certified for lead, at the tap, is usually more effective.
How often do filters need changing?
On the manufacturer’s schedule. Old filters can stop working and even grow germs.
Is filtered water better for showers?
Many people prefer how it feels and smells, especially with chlorine removed. That’s a comfort choice, not a medical claim.
Planning a remodel? Ask us about clean water at every tap. Start the conversation
Part 6 of 7 in Healthy by Design, our Wellness series in the Journal. Next: How Does Daylight in Your Home Affect Sleep? See how Greenberg builds for wellness.