Plumbing your Camper Van

camper van water tank


Water is certainly something you’ll always need to have available when you’re travelling or living in your van. Having a proper plumbing system can be more straightforward than you might think.

You can make them quite simple using refillable plastic 20L containers that have a twist “tap”, or go all-out with a water heater, sink, tap, filtration system, indoor or outdoor showers, and cassette toilets.

You should ask yourself specifics before you start like why you need water in your van, and what you will be using it for.

Depending on your lifestyle this can make your plumbing more elaborate, or incredibly simple.

For example, instead of having a shower in your van, you might choose to use facilities like gyms or truck stops that have amenities. But, if you’re on the road a lot and going off-grid, or really into sports where you might get sweaty or muddy, having a built-in shower can be something you thank yourself for later.

Depending on your needs, you will need to decide what you feel comfortable compromising on and how that works in with your travel plans.

Once you’ve got those details laid out, it’s a good idea to consider how much space you need for the amount of water you want to carry with you. Some people choose to have containers for fresh and grey water set up under the sink.

In our van builds however, we like to use our custom 22 Gallon wheel well water tanks to save that space under the sink for storage or anything else really!


camper van water tanks


Typically the space around the wheel wells can go unused, so we made these tanks formed to fit and store an excellent capacity of water for whatever you need. Double up with two tanks for the right and left wheel wells, and you have an excellent supply that can handle your demands for just about any trip.

You can buy those from us right HERE

We currently make these for Promaster vans, so keep that in mind depending on what you’re working on.

Some DIYers choose to store their water in underslung tanks, which mount underneath your van. This can save you some space but you’ll need to think about heating and insulation elements so it doesn’t freeze on you in cold weather!

You should also think about weight,  since 1L of water =1kg. The water itself is heavy, but so are all the fixings you can end up using while setting up a bathroom.

We love our custom water tanks because they help balance the weight over the axels of the van!

Expense is definitely another factor - the larger tanks can be more expensive, and depending on your design you might end up spending more for high-tech systems.

You will also need to figure out how you plan to refill your water, since different setups can be easier or more complex. Generally the more high-tech ones come with the convenience factor - but if you’re just doing the bare minimum of using smaller hand-portable tanks, expect to be pulling those in and out of your van all the time to fill up in grocery stores or wherever you choose to get water from.

The next step is to design your system according to your water usage needs.

It will need the following elements in order to function properly;

1. Fresh water tank(s)

  1. Water pump (to move the water to your usage point)
  2. Sink/Tap
  3. Wastewater tank (to store the used water that goes down the drain)
camper van water tank

To calculate your usage, you will want to measure how much water is used per day, per person.

Generally you can mostly get away with assuming the average person will use 5-10L of water per day, and adding 10L for each shower they take. If you’re a couple, you can save water by sharing showers. If you have kids or pets, you'll want to add some extra water for their showers.

Once you have a daily use number, multiply that by how many days you want to go before refilling the tanks. That will show you how much water your tank will need to hold.

Next, you will need to sort out your grey/waste water tank and how you’ll be disposing the used water inside. Some people also put that into a secondary underslung tank to keep it out of the way and give easy access to empty it. The size of the tank will also similarly vary depending on your usage. If you’re doing a small container for your grey water tank, you’ll probably be emptying it every day. It’s best to find a balance between reducing the amount of times you need to empty it, while also not adding too much weight to your build.

Another thing to note is that you’ll likely want to be using 100% biodegradable soaps and cleaning products in your van. If there’s no chemicals in your waste water, you’ll have an easier time finding places to dispose of it responsibly. 

You may also want to include a water level monitoring system so you know exactly how much water you have before you need to refill. This is especially useful if you’re going off-grid and need to plan pretty well in advance. They can also measure how full your wastewater tank is so you know how long you have to empty it before it becomes a problem! Especially if your tank is undermounted, you don’t really want to have to crawl under the van to see what your levels are.

If you’re using certain types of toilets, you may also need a blackwater tank for toilet waste. If you use a composting toilet you won’t need this, but if you want a bathroom that’s as close as you can get to a household one then this is something to factor into your design process.

There’s tons of different options for parts to use for things like water pumps, showers, sinks and taps - and we do have recommendations for some that we use in our builds right HERE to help you out with your plumbing needs!