Shower head valve

Cut your hot water waste while you wait for the shower to warm up

A shower head valve is a great way to cut hot water waste if you like to keep busy while waiting for the shower to warm up. Maybe the following routine sounds familiar to you; it’s one I see every time my wife takes a morning shower.

First, she turns on the hot water. Then she busies herself with other morning toiletries while she waits for the shower to warm. She doesn’t check every two seconds for the shower to warm up – she just gets to it when she’s ready. If I have already been shaving, I’ve used warm water in the sink, which means the shower will warm up almost instantly. If she gets into the bathroom before I do, the shower could take a lot longer to warm up. No matter; she waits at least 30 seconds before jumping in, longer if she gets busy brushing her hair or – you know.

The end result is that at least 10-20 seconds worth of hot water just runs down the drain; sometimes a couple of minutes’ worth. Now that may sound like nothing, but when you’re trying to cut your energy use to a bare minimum, as I’ve been doing for years, it can be a bit disturbing to see even a small amount of waste.

A shower head valve such as the Evolve showerhead adapter is the perfect way to solve this type of marital strife. You attach it to the water pipe coming out of the wall in your shower or bath stall; turn the shower to hot, and this shower head valve lets the water continue to flow, until the water is hot. It then drops the flow down to a trickle, so almost no hot water is wasted. You can brush your teeth, floss your teeth, read War and Peace (well, the first few pages anyhow) and still almost no hot water goes down the drain. Then you disrobe, hop in the shower, and pull the shower head valve pull cord, and the hot water is instantly on.

Show me the money

What is the payback on a device like that? It depends on a number of factors: how many showers are taken in your bathroom per week, how long the average (or worst) person leaves the shower running without checking if the water is running hot, and what the flow rate of your shower is. In my household, I’m the only one obsessed (or masochistic) enough to hop in the shower first, then turn the water on and wait for it to warm. (Just turning the shower head away from me towards the shower curtain or wall means I stay relatively warm while the water heats up.) The other three in my household generally turn on the water, wait, get distracted, and some time later hop in.

Let’s assume an average of two showers a day and an average of two minutes per shower of hot water running down the drain needlessly: that’s four minutes per day of hot water. A low flow showerhead should use 2.5 gallons or less per minute, so that’s 10 gallons of hot water we probably waste in our household a day to preheat the shower. In Toronto where I live, the water coming into the tank comes from the frigid depths of Lake Ontario (a constant 4 degrees Celsius or 39F); the temperature coming out of the shower head is typically close to body temperature – let’s say 37 C or 99 F, so we have to raise 10 gallons (38 liters) of hot water a day by 33 C or 60 F. With a standard electric water heater, this would take 1.47 kwh . With our super efficient heat pump water heater, which operates (in warm weather at least) at a Coefficient of Performance (COP) of 4, meaning four units of heat are produced from one unit of electricity, that uses a mere 0.29 kwh.

At the average electricity cost in Ontario of 14.1 cents per kwh, the cost for an electric hot water heater would be 20 cents. For my heat pump water heater, that cost is closer to 5 cents! That means we’re spending (wasting) an extra ten cents a day. You can buy the Evolve shower head valve for around $35 USD, which is around $48; $48 divided by $0.05 works out to 960 days. This showerhead valve pays for itself in under three years. So it definitely has a reasonably good payback time.

Features of the Evolve shower head valve

Like other water saving shower heads, the Evolve shower head volve is a fairly simple mechanism – batteries not required – and it simply drops flow to a trickle once the water reaches full heat. You can usually hear a shower pretty loudly even from the next room, so it’s easy to tell when your shower water is hot enough. When things quiet down again, you can walk into the bathroom at your leisure, hop into the shower, and pull the cord.

This shower head valve does not prevent scalding, of course. If you are using a regular sequential shower valve (one that blends hot and cold water according to a dial setting), make sure you set it at the typical temperature you shower at. In our hose that means at the “2 o’clock” mark. If you turn it all the way up, you’ll use less water overall, but you risk scalding yourself when you hop in the shower and pull the cord. There are two types of standard shower valves in the plumbing for your shower – manual or thermostatic. A thermostatic valve includes a device that shuts off the water flow if the temperature reaches scalding, to prevent burns. If you have a manual device you could be in for an unpleasant surprise. But if you follow our guidance to turn your hot water heater down from the factory default setting of 140F (60C) to 120F (49C) the risk of scalding is significantly lower, plus you’ll save energy!

The valve is usually easy to install. Just unscrew the showerhead or shower hose from the wall pipe, add some Teflon plumbing tape around the thread on the wall pipe and screw the shower head valve in place. Then add more plumbing tape on the threaded end of the shower head valve, and screw the shower head onto the showerhead adapter. You can hand tighten, or if necessary tighten gently with a plumbing wrench.

Early on, the Evolve shower head valve was available on Amazon and got great customer reviews. It’s now only available, from what I can tell, on Evolve’s own website (thinkevolve.com). As I’ve already pointed out, even in my highly energy efficient household, the payback period is under three years – and that’s just counting the cost of the electricity saved on heating the hot water. If you add in the amount of water saved – 3,650 gallons a year for us – at about a half cent per gallon, that’s a whopping $18.25 per year, which cuts the payback time even further.

While I’m not a big fan of gadgets for gadgets’ sake, I believe this water saving device deserves consideration by anyone trying to cut home energy use and water use. In any situation where water rates are high (such as dry climates in the US southwest) or the cost of heating water is high (either because of the high temperature difference, in cold climates, between intake and hot water tank, or because of high energy prices), a showerhead adapter such as the Evolve shower head valve can make already energy efficient shower heads even more efficient. We need to learn to think of such devices as investments not as expenses, and an investment that earns its principal back within the first year just keeps on producing profit every year afterwards. And based on the sturdy chrome construction and the simplicity of the design of this shower head valve, chances are it will last you many years.

Make sure you use a low-flow shower-head

If you have a rain shower head or other high volume shower head, it probably doesn’t make sense to invest in an Evolve shower head valve; you’re better off instead to switch to a low-flow shower head valve. The maximum flow of a shower head valve, including a rain one, is 2.5 gallons per minute (GPM). This is by law, in order to reduce energy and water waste. A low flow showerhead meanwhile, is required to be at or under 1.8 GPM. You’ll save a lot more money cutting your shower water use by 28% by switching from a regular to a low flow showerhead, than by installing a shower head valve. Of course, even better, you can do both!