Dishwasher supply valve

New construction. Single valve for kitchen sink hot water and dishwasher. I say there should be separate valves for each fixture. What say you?

Here’s the photo.

Typical…in fact most homes I inspect with a dishwasher has a stop valve with a double connection, which is essentially the same thing you have here… One for the sink faucet, the other for the DW. Water does not run to the DW the entire time the unit is working. It only fills it for the wash and then the rinse cycle. I have never seen a separate valve for the DW in thousands of inspections.

I have an identical set up on my cold water shut off valve for a water filteration system.

Are you saying that if I disconnect the dishwasher supply line, it will not leak if the valve for the sink is open?

Not at all what I am saying. It is simply an “in-line” connection in the hot water supply line. The DW itself has a valve that electrically opens and closes, thus calling for and allows water into the DW. It is no different than any other water supply line. The stop valve allows the individual to shut off all water to anything downstream of the shut off. If you take the supply line off at that connection there is still going to be constant water pressure on the line unless you first shut off the water at the stop valve. It will not just leak you will have a geyser coming off the side of the connection.

Another example of this type of supply would be a “saddle valve” that we see all the time on retrofitted water supply lines for things like ice makers.

That is the reason why I think there should be separate stop valve for the dishwasher. If there were to some sort of leak at the dishwasher or dw supply line you would need to shut off the hot water to the sink. My understanding of the IRC and UPC are that each fixture should have a separate valve.

I always see a separate valve over here. It must depend on the area that you live in.

I have seen it both ways, but twice last week with no separate valve, and started to wonder which was right. I did a bit of research and have concluded that a valve should be installed.

Had to leave for a bit, just got back. Here is the typical set up with a twist. In this photo on the left is the hot water stop valve with two connections, one for the dishwasher and one for the faucet. On the right is the cold water supply riser with a type of saddle valve that literally taps into the copper line. This was for the ice maker in the refrig. There is only one shut off knob or valve for each side. This is what we typically see around here. I take back what I had said earlier. I have seen one (and only one)with a separate valve for the dishwasher. It was in a very high end home we did a few months ago, but those folks did not spare on anything. I had forgotten about it until I thought about it for a while.

Along that vein, I have seen crap that people (including licensed plumbers) have cobbled together that while not pretty, did not violate any codes or laws and did not leak.

It is a common set up and I would not call this a “defect.” However, most new construction will have a separate valve.

I like the pic Doug, but I would be a little concerned about where the wall plug is placed. It might just be the angle of the pic, but it looks like the two right hand outlets wouldn’t be useable. Not to mention what might happen if there were a leak in the cold line, especially at the saddle valve, and let’s face it most will leak at some point. It looks like the hot water line has already leaked some what given all the corrosion present. Anyways this is just my opinion. Around here, I always see it done the way you have shown here a stop valve with two connections.


The Florida Building Code Plumbing has required since 2001 shut off valves on the fixture supply to each plumbing fixture with the exception of tubs and showers in residential occupancies. FBCP 606.2.1 If the local AHJ is allowing more than one fixture or appliance to be serviced by a single valve in my opinion they are not interpreting the code correctly. Using that interpretation since the home must have a shut off valve at the service entrance just add a second shut off at the water heater hot side supply and you could then eliminate every other valve in the home

I almost had to laugh out loud. The local AHJ(s) has never worried about following the codes beyond what they want and the local builders want. Each county inspectors’ offices interprets and uses them the way they want to, often omitting things or deferring to later dates.

The 2 way in the picture was standard issue when I was working for Sears.
Calling something like that out might cheapen the worth of the rest of your report.
What possible issue is foreseen here other than not being able to use the Dishwasher while changing the faucet.OMG!:shock:

Would you say the same thing if there were no valve on the cold water supply for a water heater?

Is it on a 2 way valve.(apples and Oranges)
Tell me what the issue is with a 2 way valve on a hot water supply line and dishwasher again?

Very rare occurrence John that would happen, but seen it before.
Some of these old houses had very few valves and when you needed one, usually the main shut off valve was the one.

Of course in today’s world of new homes and codes, valve stoppers are a requirement in most states.
I wish I had a valve on my dishwasher, I have to go in the basement and shut off the sink too.
Every valve I have usually leaks by and have to use the secondary (main).

Not a defect unless in a new home where it was required by IRC and Jurisdiction.
Upgrade would always be an added benefit for a client. :mrgreen::wink:

What does the AHJ require?,17315,23628,23670,23945,25646,25834,26328,26569,26745,26762,26849,26885&sugexp=ldymls&xhr=t&q=2+way+shut+off+valve+on+dishwasher&cp=14&qscrl=1&um=1&ie=UTF-8&ei=fHmqTKvnNMK5jAe0opG2Bw&sa=X&oi=product_result_group&ct=title&resnum=11&sqi=2&ved=0CFsQrQQwCg

What’s the big deal. Ive been in my house 20 years. Put in a new faucet and dishwasher when I moved in. Haven’t turned off the hot water since. My mom has been in her house 57 years. Changed the faucet once. Only time the water has been turned off under her sink.

I see separate valve on new construction 90% of the time. Almost never on old construction. Not a deal breaker.