Most softener retrofits soften the entire house. Doing it that way all the plumbing, fixtures, and appliances get the benefits of soft water.

The easiest and most cost effective installation of a softener loop is where the water service enters the home. At that location you also need a drain and except a Kinetico softener you need electricity.

oh. so most do to to the whole house?

mine was done when the house was built- (has pipes in garage for water softener to go)

Some houses are pre-plumbed for a softener. Some are plumbed to soften the entire house while some leave the outside hose bibs and kitchen hard and some only soften the hot water.

IMO, if you're paying for soft water you ought to have it. With hard water like yours you may may or may not like the taste of softened water. If not, then I recommend an Reverse Osmosis (RO) unit under the kitchen sink for cooking, drinking, and your ice maker if you have one. Then you';ll have water at the sink just like you buy at the water machine at the Wal-Mart or supermarket.

If you wash your car with 20 gpg hard water you'll wish you had soft water ;)

Drinking softened water is often not advised due to hight sodium levels. Softening irrigation water is a waste of salt and might be an undue burden on the environment. Both softened and unsoftened water at the kitchen sink is a good idea, the former for washing and the latter for cooking and drinking.

How to tell if the water is softened at each tap? Can't you turn off the softened water and see what happens at the taps?

If not, that is a tough one. It depends on what makes the water hard and how hard it is. You could try mixing a little old fashioned soap with samples and shaking them up. Soap will complex with divalent and trivalent cations and interfere with formation of suds. Nonionic detergent won't work for this. You need something like sodium dodecyl (sodium lauryl) sulfate. Start with something that you know is soft and use the minimum amount of soap that you need to get a few bubbles.

You might also let samples dry and look at the appearance of the residue.

Drinking softened water is not advised when specifically told by a doctor due to hypertension.

High sodum levels in soft water is more of a wives tale than reality. The higher the hardness the higher the amount of sodium ions exchanged into the hard water to soften it,

The formula for added sodium is 7.85 mg/l (about a quart) of softened water per grain per gallon of compensated hardness.

EXAMPLE 20 gpg * 7.85 = 157 mg of sodium added per liter of softened water

If one has hard water, as the OP does, then an RO is recommended and was by me.

" Softening irrigation water is a waste of salt and might be an undue burden on the environment"

The OP did not mention irrigation and for that purpose untreated water would be available from the well BEFORE the sofftener.

The current RDA for sodium is 2400 mg/day. A couple of liters a day using your figure would be over 10% of of that. Some authorities think that 2400 mg/day is way too much. It is certainly too much for sodium-restricted diets.

The second half of your calculation is pretty good since 20 GPG is higher than just about anyone will see.

What homeowner does't irrigate at some time or another? If the reader never irrigates plants, then the reader can dismiss it.

What well?

"The second half of your calculation is pretty good since 20 GPG is higher than just about anyone will see"

Really? You must have limited experience in water treatment and in a very small area.

My water runs 30 gpg and I'm on a water system. Wells around here run in the 60 gpg and 70 gpg hardness range and I've seen one well a touch over 100 gpg. A little Googling and you'll find that 20 gpg is hardness that many people around the US would wish for.

If you're concerned about any additional sodium in your softened water, regardless how small the amount, you can use KCl (potassoium chloride) as a regenerant and completely eliminate that concern.

I live in scottsdale,az- i know the water is running 25+ gpg. If I could choose, i'd rather not have the outside be softened. But It is already done. I do not have a water softener yet, so I can't turn it on and off to test. Is there no way without a plan or opening the pipe and measuring pre/post levels, to see what is in the circuit?

Even if you had the blueprints from when the house was built plumbers don't seem to follow them.

Phoenix, and every where in the valley, has awful water. Almost undrinkable. I think you'll agree that lots of people there only drink bottled water... right?

If you provide the # of people in the house, the # of bathrooms, and the kind of appliances you have along with the detailed water conditions I can recommend a correctly sized softener set for efficient operation that will waste very little water and regenerant EVEN softening the hose bibs.

I have 30 gpg water and use one bag of KCl a month. My entire hpouse is softened and we water inside and outside plants and wash the cars... soft water leaves less water spots than hard water... car washes wash cars with soft water.

I have an RO under the kitchen sink for cooking and drinking and making the best coffee and the clearest ice cubes I've ever seen.

Here's what I recommend...

Water softener 101 ...

Get a water test from an independent lab. An independent lab has no agenda and won't be trying to sell you water treatment equipment. This is a MUST DO because without it everything is a guess. A quickie water test from Sears or a water softener company won't be as accurate (and possibly not as competent) as from a certified independent lab.

If you're on a water system the water utility can supply you with the specs of the water AS IT LEAVES their facility but that is not necessarily representative of the water conditions at your water meter.

Hit the Yellow Pages and call at least three local water treatment pros. Make sure you call at least one of the big dogs like Kinetico or Culligan for comparison and at least a couple independent pros. DON'T TELL THEM YOU HAD YOUR WATER TESTED.

Give each an opportunity to offer suggestions and provide you with a quote to meet your water treatment needs. IGNORE ANY THAT DON'T TEST YOUR WATER THEMSELVES as they can't speak intelligently to water treatment without knowing what needs to be treated.

Ask lots of questions. Warranty, parts & labor or just parts, how long and on exactly what? Install, permits required, licensed plumber? Routine maintenance and costs? Do they stock parts? Response time for emergency (water leak) calls? If they don't explain things to your satisfaction that is a good indicator of how you'll be treated after the sale.

After they've gone use your water test to compare with theirs. Are all your treatment needs being addressed?

Ask your neighbors if they have any water treatment experience. They might tell you who's good or who to avoid.

Come back here and post the specific recommendations and hardware components with the costs and we'll give you our opinions.

The simple answer to all this is have the water tested at all sinks in the home to be sure they are on soft water.
You can take samples to your local water treatment dealer and have them test for soft water. They should not charge for this.
Short of that, go to where the point of entry for water is.
If the plumbing goes directly into softener then most likely all the water in home is on soft water. If softener is installed there should be a separate line feeding the outside spigots before water softener for hard water.

Turnoff the inlet to the softener and see what fixtures have no pressure.

I did one of the home test, which was good except of course for hardness. I was going to go to the private lab, but quick goole search didn't fine one. (than I got distracted with other things.) do water treatment plant do this for you? there is one a few blocks away, so that would be great.

Here is a list of Arizona Certified Labs

Here is a link that might be useful: List of Arizona Certified Commercial Drinking Water Laboratories