Whole House or Point of Entry Water Filters?
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I’m looking to add water filtration to my home, and am trying to figure out whether a whole house water filter, or individual point of entry water filters (ie, at the sink) would be better. It might be easier to just have the one whole house filter installed, but I am wondering if I will ultimately end up filtering a lot of water that doesn’t need to be filtered, as opposed to just putting filters at the sinks were water is actually used for drinking, brushing teeth, etc. I also wonder if there is an issue with water being recontaminated in the homes pipes after being filtered with a whole house filter. Any thoughts appreciated.
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Replies
you need to let us know what the contaminant is you are filtering out. if it requires a reverse osmosis filter then that would typically need to be point-of-use at the kitchen sink with a feed to the ice maker. reverse osmosis water dissolves copper pipe and brass fittings so, if your water is bad enough to require a whole house reverse osmosis system you need to plan for it with an entirely metal free distribution system and major leak protection at the water heater as well as a calcium carbonate neutralization tank immediately after the reverse osmosis unit.
Typically you will do a whole house ionization water softener (which requires adding salt periodically) and some type of acid neutralizer or a berm tank for moderately bad water or a simple and inexpensive whole house 9" cartridge filter for mildly contaminated water.
I have my water samples tested by Lancaster Pump through Ferguson Enterprises and buy treatment equipment from Ferguson as well.
Hi Brian, the first place to start is whether you have municipal water or well water. Then, as Michael says, establish which contaminants you wish to have filtered. If municipal water, it's typically chlorine, chloramines (to prevent disinfectant byproducts from becoming an issue in your home), heavy metals, pesticides, herbicides and sediment.
For well water there can be a huge variety of issues such as iron, sulfur, hard water (can also be an issue with city water in many cases), bacterial contamination, nitrates, etc. The list for well water issues can be quite long. Having your water tested for a wide range of contaminants, pH, hardness is the only way to know for sure. Contact a qualified lab to have testing conducted.
When deciding about whole house vs. point of use filtration, it is often cheaper to filter at the whole house level even though it may not seem that way at first. The advantage is that all water - for showering, drinking, laundry, pet water, cooking, etc. is all filtered. While it may seem like its not necessary to filter all the water in the home, you will find that it's great - only one thing to maintain. Also - it's much healthier, particularly for showering if you install a whole house water filter. There is a growing body of evidence about showering and bathing in chlorinated water and its affects on your health.
The disadvantage to whole house filtration is that it cannot provide hyper-filtration like a reverse osmosis unit can. The RO will take care of inorganic contaminants you may be concerned about such as fluoride, pharmaceuticals, sodium, nitrates, etc.
Many homeowners decide to go with both to have the benefits of both whole house filtration as well as point of use. This also eliminates any concerns you have about re-contamination of water by the home's pipes.
Maria Williams, PuriTeam.com, CleanWaterMom.com
Bull droppings... I know many a chlorinated water drinker in their 90s. Any study that I ever heard of sounds great alarms... then the details.... (possible that 1% are affected... we're still studying... blah blah...)
Easy to market something by scaring the daylights out of us though.
aj (butter and bacon lover with a 130 cholesterol level... 3 eggs or more a day guy)
Some may need water conditioning... but hold the hoopla please.
Edit; I have to say there are some great ads for water filtration that pop up when accessing this post. Dan, you would be proud of me as I have actually clicked through some of your ads. Hope I have added a few cents to the pot. Love Fine Homebuilding and GBA.
Actually municipal water may well have bull droppings, leaf mold and other biological and chemical ingrediants that when filtered and treated with the combination of chlorine and hydrogen peroxide (more economical than chlorine alone) produce toxic nitrosamines (http://www.cdph.ca.gov/certlic/drinkingwater/pages/NDMA.aspx)
Maria's point about treating the shower water is really crucial. Many contaminants and bacteria (Legionnaires) are taken in through the lungs in the shower steam as well as through the skin. I don't generally promote reverse osmosis filtration unless we see high levels of petroleum or heavy metals in the test and when that happens we generally want to see tests taken over a couple of two week intervals and check for draw-down factors. if a well has a low yield (less than 2 gpm recharge) you can get some odd run-time changes where the longer you run the water the more minerals are stirred up. Best to take the samples as close to the well head as possible and after a period of normal house hold usage. (not while the tile guy or landscaper have the well at maximum draw-down all day)
In NC we have had to bring in the state toxicologist on a few nasty results; gas in two different counties, one sabotage, an angry racist poured gasoline into a newly drilled well) one an ancient pocket of pre-unleaded vintage gas from an abandoned filling station. We also called him in on selenium in massive levels that cleared up after six weeks (rock dust). He's been very helpful if somewhat alarmist and exasperatingly pedantic.
I no longer get very worried about fecal coliform or surface water contamination. those we generally can fix pretty quickly. Black manganese sand is the biggest pain around here and (salt-free) berm tanks are not the magic bullet we would like them to be (for manganese and iron) as they are very subject to the acidity of the water being treated. Unless your PH is just right it's generally better to go with an ionization water softener and deal with the bags of salt.
If you do choose the water softener route I recommend that you pipe the back wash line to a floor drain as quickly as possible and run that to the gutter line rather than the septic tank. Salt will be well dissipated by rain fall and can change the buoyancy of the water in the septic tank causing the solids and oils to float more aggressively and causing the tank to go anaerobic and produce methane which eventually escapes from the roof-top plumbing stacks. A smelly situation and bad for the ozone layer.