How to Install Plumbing for an Outdoor Kitchen

So it's "How To" time again! Time to make holes and cause minor chaos and destruction.

Of course, I'm kidding, but we have all had those DIY projects that have not gone so well. The ones that haunt us through our significant other's memory.

Today let's make sure this project is productive and well thought out.

Let's talk about "How to Install Plumbing for an Outdoor Kitchen."

An outdoor kitchen is a great addition to the patio or deck. Not only does it provide you with plenty of storage options (when planned correctly), but you also have the luxury of an outdoor sink for washing up, cleaning fish, and prepping vegetables from a nearby garden.

Maybe you just want to give your preferred drink a firm place to rest while you work on repotting your favorite flower or better yet, herbs.

Steps to Plan and Plumb an Outdoor Kitchen

1. Pick a Type

Look, it's the age-old problem. It literally keeps you up at night, I'm just sure of it.

What kind of sink and faucet do I want in my outdoor kitchen?

Stainless steel, porcelain, custom, manufactured (that's just the sink), and the list goes on.

Really what you should be thinking about is "What type of weather do I have in my state?" "What will hold up to snow, rain, sleet, hail, or heat?" And of course, "How big do I want to do this thing?"

Sit down and draw a basic kitchen layout. You can do it as big or as little as you like, but make sure it makes sense on paper first. It's easier to erase than it is to dig and move. Your back will thank me.

While you're at it, jot down some finishes you really like.

A word of warning. When you buy a faucet always open the box and physically look at the finish. You would be shocked to know how many customers I have had in the past that made a purchase, got it home, and ended up taking it right back.

Why? The finish didn't quite look like it did on the box. Which is quite common, unfortunately.

Now you know the story of the faucet boxes on the shelf that look like they have been opened.

2. Pick a Location

So where do you want this grand outside kitchen? By the back alley? Just off the house? Within the area of your Patio?

Really what you need to first decide is, do you want it attached to the plumbing from the house or do you just want to hook a hose to a faucet to make it all work?

The two different styles most definitely work, but a different level of work and parts go into both.

I will try to cover both here as best as I can.

3. Connect to the Main Water Pipes

So you know where you want the kitchen. Now how do you want it to connect?

If you have decided on the easy option, which would be just to run a garden hose to the cold side of a faucet, then setting up for water will be quick. You could bury the hose to hide it on its way to the sink, but unless you are going to blow that hose out in cold weather with a compressor, I wouldn't suggest it.

You see cold weather surprises every state at some point and having your hose above ground gives you the option for a quick disconnect and put it in the garage-type scenario.

To get started if you have chosen to connect to the house, you need to run supply pipe from inside the house that is rated for outdoor use. What does that mean? It just means that all pipe will break under the right conditions but some pipe is much more resilient to the elements.

I would suggest a Pex or Poly pipe for such projects, They don't rust or burst as readily as copper or galvanized would.

Also, the tools and fittings are relatively inexpensive. In some cases, you can rent the tools if you're really on a budget.

The pipes should be held in place with two-hole clamps, nail talons, or poly plumbers tape, and you can insulate the pipe to protect it from damage, and if you are running hot water.

Remember, hot water will freeze before cold.

The pipes should be sloped back toward the house to help drainage as you will need to install two drains, with shut-off valves inside the house where you connect to the main water. We will revisit why in the winterization section.

Your pipes can be buried underground for a more aesthetically pleasing look as well, but keep a note of where they are so your teenager with the air pods glued to their ears doesn't hit the line while trying to accomplish the yard work you sent them out to do.

Keep your connection simple. A plumbing tee in your closest hot and cold line will get you where you want to be. The valves and drains for the lines don't have to be right where you tee your lines. many people put them on just before they go out of the house.

Now if you're feeling overwhelmed about connecting these lines, but you're adamant that you need to do it, just call a local plumber and ask a couple of questions. Most local plumbing shops are happy to answer questions and the best part is it's free.

4. Run the Pipe Outside

With the piping in place, running through the wall and towards the outdoor kitchen. The pipe should come up through the bottom or back of the cabinet. really its your preference.

You may need to use thread adapters to connect the pipes to the plumbing in the sink. You can at this point put regular sink stops on, like the ones in your house to turn that faucet on and off, but it's really not necessary since you have the shutoffs for those lines in the house already.

Make sure to use plumber’s tape (I suggest the blue Monster tape) on all the threaded adapters to ensure a water-tight seal.

5. Build a Drainage System

The sink will need a drainpipe for the sink trap.

The drainpipe should be PVC, only because PVC tends to hold up better when directly exposed to the weather.

If you have chosen to come from the house, simply cut a wye into the closest drain line in your house and bring that through the wall as well.

Keep in mind that the drain needs to come in through the back of the cabinet, and that it needs to drop one-quarter inch per foot back to where it connects to the house.

Why the back and not the bottom of the cabinet. Because if you come through the bottom, if you connect the p-trap correctly it can cause what's called an S-trap. An S-trap can cause the P-trap to suck itself dry allowing sewer gas into the area due to its inability to breathe or vent correctly.

When installed through the back you can add an air admittance valve and the system will breathe as it should.

So remember if you're connecting from the house then you will need a p-trap on the outdoor sink so that you don't inhale sewer gas from the house while cooking your favorite steak.

6. Dig a Drainage Hole and Drain Bucket

So where does all that rinsed happiness go if you have not connected to the drain on your house?

Well, you will need to dig a dry well for the drainpipe.

The hole for the drain bucket should be dug at least ten feet from the deck and needs to slope away from the house to prevent water from flowing in the wrong direction.

The drain line should be at least 1.5 inch PVC pipe. The slope of the pipe should be around a quarter inch for every foot at the very least.

Drill a hole for the inch-and-a-half drain line coming from the kitchen in the side of the bucket. Try to keep your hole in the top third of the bucket. You also need to punch holes into the bottom of the bucket for drainage.

The piping should poke into the bucket a few inches and rest below the ground level.

Fill the bucket with some coarse gravel to the bottom of the drainpipe to help the water drain properly and put the lid on the bucket.

Cover up your trench and drive on.

7. Winterize Pipes

We talked about weather and climate once or twice already which means depending on the climate and type of water you are running, you might need to winterize the piping.

So let me repeat this from earlier. Cold weather comes to visit every state at some point.

You can accomplish winterization of your water lines with a small pump or using a gravity system (your shut-off valves with drains), or installing the pipes below the freeze level.

What is the freeze level? Glad you asked. Freeze level for water lines varies from state to state so make sure you check your local plumbing code to find out.

In my area of southeastern Idaho, the minimum depth is 42" to the top of the pipe. Anything more shallow than that and the line will freeze and potentially cause damage to the pipe or make its way back to the house causing some unforeseen basement flooding action.

If you should choose to use a pump it will help remove water by forcibly clearing the lines, while a gravity system will flush water naturally from the system via a drain.

Sink Drainage Notes

If you elect to use a dry well to drain the water in the sink you will be limited on the use.

Without a garbage disposal, you will not be able to put food scraps down the sink.

You can still wash like you would in your indoor kitchen sink, but placing food scraps will lead to a smell that will not soon leave your nostrils, will not impress your spouse, and might plug up the system.

Of course thank God for Redneck engineering, because if building a drainage system isn’t an option you can always place a bucket underneath the sink and empty it whenever it gets full or starts to smell like sushi that's been left out too long.

Sink and Faucet Tips

Selecting the right kind of sink and faucet to install is an important step in building an outdoor kitchen.

Of course, you want it to be functional and look good, so let's take a look at a few things.

Stainless steel is a great option for the sink because it is both durable, easy to keep clean, and shiny. Who doesn't like shiny?

Copper and bronze sinks (although beautiful) are alternatives, though they tend to develop a patina after extended use.

Brass, meanwhile, is a good option for the faucet as long as it comes with a physical vapor deposition finish.

Try to avoid faucets that have plastic parts or rubber buttons as they can slowly degrade in the sun.

Conclusion

So we have talked about the simple yet labor-intensive way of installing an outdoor kitchen.

We have also talked about the home intrusive way of cutting into the plumbing lines of your own home, dragging those lines outside, and making an awesome workspace.

Hopefully at this point, the only thing left for you to do is pick the color of your outdoor mini fridge to hold your cold beverages while you kill it on the new grill going right alongside your new kitchen.

Well, maybe a new grill. One can always hope.

Go, build, and above all else enjoy yourself.