Is a Whole House Reverse Osmosis Water Filtration System Necessary?

Posted by
Freeman Linton

Do I Need a Whole House Reverse Osmosis System?

If you like the water produced by your reverse osmosis drinking water system at your kitchen tap, wouldn’t it make sense to install a whole house RO system?

Maybe not! Here's why Whole House RO May not be the Right Choice:

RO has its' place in the water filtration and purification realm. But when it comes to whole-house water filtration, RO systems typically aren’t the best solution when looking for a way to have better water in your home.

QUESTION: When does a whole house reverse osmosis system make sense?

RO systems are great at removing lots of different contaminants from the water. A whole house RO system may be the right solution when you have a high level of a specific contaminant that is most economically removed by reverse osmosis. If you have a specific contaminant present in your drinking water that is of concern, a water professional may recommend whole house reverse osmosis as the best solution for that contaminant.

6 Reasons Why Reverse Osmosis Systems are Rarely Used for Whole House Filtration:

Whole House Reverse Osmosis System Can Be Expensive: A whole house RO system is expensive (~$3K) and often requires pre-treatment of the water before the RO system (such as a water softener). A pH neutralizing system is commonly installed as post treatment to bring the pH level back to 7. This is followed by a 200-500 gallon storage tank to store the treated water in. Then a demand pump is needed to push the water from the storage tank into your home. This is typically followed by a whole-house UV system to disinfect the water after it’s been in the storage tank. Thus, a whole-house RO system, along with all the required pre and post treatment equipment, can be cost prohibitive.
Whole House RO System Maintenance: Whole-house RO systems, along with the other associated systems and equipment, require a knowledgeable and professional installer and service person to properly maintain the systems and replace the filters, RO membranes, and UV lamps.

Whole House RO Consumes a Lot of Water: RO membranes work by flushing water over the membrane element. Some water is pushed through the element at filter water and the rest helps flush contaminants down the drain. Large RO systems use a lot of water. Because it takes about 2 gallons of water to create one gallon of filtered water, you can expect your water bill to double with a whole house RO system.

Flushing Filtered Water Down the Drain: Since most of the water used in the home is NOT consumed for drinking, but used for flushing toilets and bathing, it’s typically not necessary to have RO quality water for your whole house.

Pre and Post Treatment Needed: As mentioned, a whole-house RO systems can rarely be installed alone. Proper pre and post treatment may need to be installed for your system to function properly over time. If your water contains high levels of iron, sulfur, or is high in calcium (hard water), then those contaminants may need to be removed prior the reverse osmosis system. FYI--85% of homes in the US have hard water, so there's a good chance you'd need a water softener.

Required Space: Whole-house RO systems pre and post treatment require a large storage tank for the treated water. All of this equipment also requires a lot of space in a garage or well house, that is often not available.

QUESTION: What's the Best Option for Whole House Water Filtration?

When looking for better water for your home and family, there’s no set answer. There are a lot of factors that can determine this answer for your home such as size of house, number of people living in the home, pipe size, well water or municipal water, and contaminant levels present in your water. 

For most homes on municipal water, we often recommend a cost effective, environmentally friendly, compact solution for whole house water filtration and purification. Typically, this would include the following at minimum:
  1. Whole House Sediment Filter System: Removes fine (microscopic) sand, silt, dirt, and rust from the water that protects the other filters and all your water using appliances.
  2. Whole House Carbon Filter System: Really helps improve the taste and odor of the water by removing chlorine and lots of other contaminants (What can carbon remove?)
  3. Whole House Ultraviolet System: Disinfects your water from 99.99% all micro-organisms including E. Coli, giardia, crypto, viruses, and bacteria. This ensures all the water entering your home is microbiologically safe for showering, drinking, and brushing teeth. A great compact combo system that includes a sediment, carbon, and UV filters in one system, is the Viqua HIS22-D4 water filtration system.
  4. Undercounter Reverse Osmosis System at the Kitchen Sink: A small RO system will provide bottled water quality for drinking and cooking with at the kitchen sink. It’s small size and low price point make can make it extremely economical for the quality of water produced. For compact size and easy of use, we recommend the PuROTwist RO system.

In addition to the four system recommendations above, your home may need additional systems for removing specific contaminants, such as high levels of hardness (calcium and magnesium). This would require a water softener,or alternative, to remove the hardness or the effect of hard water. 

Hard water can cause scale to buildup in your hot water heater, pipes, and water using appliances. It can also affect the effectiveness of the other water filtration systems.If you have hard water and need a water softener, ESP Water Products does not sell water softening systems and recommend you contact WaterTech.com and find a local dealer who can assist you.

If you have questions about what systems will provide the best water for your home, please call our team of water experts Monday through Friday, 8 am to 5 pm CT,at (877)377-9876. They'll talk you through a variety of options to help you determine which systems best meet your needs.

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