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Plumbing Water Controls

Star Turning water on and off, and controlling volume and temperature, eg in showers.


Fixture general principles

For point of use fixtures such as showers, sinks, and baths there are various control functions that are required:

1)  Set temperature
2)  Set flow rate
3)  Turn on and off (may be combined with flow rate control)

Temperature setting

The temperature setting mechanism needs to meet ASSE 1016 point of use plumbing code.  It can be done with a thermostatic mixing valve that mounts on the wall or out of view under the countertop.  You can mount a user accessible thermostatic mixing valve on the wall or you can hide it under the counter and use it without the trim fitted.

Thermostatic Mixing Valve (Wall mount)

Thermostatic American Standard rough-in Details are here .

Plumbing temp control on box 

The trim needs to be brought separately.

Trim for Thermostatic Mixing Valve (Wall mount)

Thermostat American Standard Chrome 

In many situations, you can share a thermostatic valve between more than one fixture, eg a shower and a sink faucet and/or a bath.

Thermostatic Mixing Valve (Hidden)

The problem with these is that they typically do not meet ASSE 1016.

Thermostatic mixing valve Details are here .


Flow rate setting (and on/off)

This determines the volume of water that flows.  Sometimes it comes after the thermostatic mixing valve, ie it is controlling the volume of warm water.  Typically the volume (flow rate) control is also able to shut off the water completely, ie it can also perform the on/off function.

On Off Volume Control Valve

On Off Volume rough-in Details are here .

Volume valve on box 

When running PEX pipe from the output of the valve to the wall outlet it is best to keep the pipe lower than the outlet so the outlet does not run-on after the valve is shut.  It practice this means the water inlet pipe needs to come in from above.

The trim needs to be brought separately.

Trim for On Off Volume Control Valve

On off tap chrome Details are here .

In showers as a cheaper alternative you can use shut-offs that mount on the NPT threads where the shower heads fit.

Shower Shutoff NPT

Water controls Rough-In

It is important to get the plumbing valves and other brass plumbing fittings the right distance behind the finished face of the wall.  The finished face typically means the face of the tiles.  Behind the tiles is Kerdi waterproof membrane with its two layers of thinset, and the drywall behind that.  You need to do a CAD drawing to show exactly how far behind the finished wall surface the valve should be mounted when it is roughed-in.

Plumbing Rough-In

I glue on some 2-by wood flat to the surface of the ICF Concrete (after the ICF EPS has been stripped away).  The plumbing valves are held onto the 2-by wood using 3/4" electrical conduit plastic loop straps.

Mounting Boards For Plumbing 


Shower control config

By code showers must be at least 30"x30" with door opening outwards and with door opening bigger than 22".  The shower temperature control must meet ASSE 1016.

If you do not need to conform to code (ie do not need an ASSE 1016 temperature control and can make do with a pressure balanced temperature control) you can use an integrated shower assembly.

Integrated Shower Assembly   Integrated Shower Assembly

Shower On and off

Use a volume control valve (as described above).

Shower head turn-off

Typically there will only be one volume control knob that turns on the shower.  The shower will typically have various different heads.  If you don't want a particular head to be on or if you want to limit the flow from that particular head then a shower turn-off that screws onto the NPT thread before the head is a cost effective way of doing it.

Shower shutoff NPT Purchasing details here .

Shower head diverter

If you want an attachment for a flexible shower hose, rather than use a right angle wall elbow you can instead use a diverter so that the outlet can also be used as an auxiliary shower head when the flexible hose is not being used.

Shower diverterPurchasing details are here .

Flexible shower wall elbow

If you never want the outlet to be an auxiliary shower head then you can just use a wall mounted elbow outlet.

Flexible shower wall elbowPurchasing details are here .


Flexible shower hose

Flexible shower hose Purchasing details are here .


Flexible shower head

Flexible shower head Purchasing details are here .

Flexible shower head holder

Flexible shower head holder Purchasing details are here .


Shower arm (bent)

Bent 6in shower arm Purchasing details are here .


Straight shower pipe

For auxiliary shower head outlets you typically want to use a short straight shower pipe.

Threaded chrome pipe 

Chrome flange for pipe Purchasing details are here .

Plumbing outlet tube screw   Details here .


Shower Head (LED)

Shower head LED purple   Details are here .

Shower Drain

For showers you need a good sized drain.  Using 2" diameter drain is sufficient for all but the highest volume showers.

Shower drain 2in ABS Details are here .


Motion Activated Faucet

Motion Activated Faucet

Motion Activated Faucet

Motion Activated Faucet

Motion Activated Faucet

Motion Activated Faucet

Motion Activated Faucet