Tanks are an essential component of van builds, allowing van dwellers to have a reliable source of water for all their daily needs while living off-grid. There are three main types of water tanks in van builds, each serving a different purpose: freshwater tanks, gray water tanks, and black water tanks.
In short, freshwater tanks store clean, potable water that can be used for cooking, drinking, and washing. They come in various sizes and materials, including flexible water bladders, rigid plastic tanks, and stainless steel tanks. The size of the tank will depend on the needs of the van dweller, the available space in the van, and the duration of the trip. A freshwater tank should be designed to prevent contamination and ensure that the water stays fresh and safe to use. This may involve the use of a filtration system, UV sterilization, or other treatment methods.
Gray water tanks are used to collect wastewater from the sink, shower, and other sources, excluding the toilet. Gray water tanks are available in similar materials to freshwater tanks and should be designed to prevent leaks, odors, and contamination.
Black water tanks collect waste from the toilet and are typically the smallest and most specialized of the three tank types. They are usually made of rigid plastic and must be designed to prevent leaks and odors. Black water tanks require regular maintenance and may require additional treatment methods such as chemical additives or composting systems to break down the waste and reduce odors. For more detail on each tank type, see: What are the different types of water tanks for custom van builds?
When choosing a water tank for a van build, several factors must be considered. These include the size and weight of the tank, the available space in the van, the durability and lifespan of the tank, and the type of material used in its construction. By selecting the appropriate type and size of water tanks and associated components, van dwellers can ensure that they have a reliable source of clean water for all of their daily needs.
Available Space
The size and shape of your van will be one of the biggest factors in selecting a water take. Your van dimensions and available room to place the tank will impact the size and shape of water tank you can install. Before choosing a water tank, measure the space where you plan to install it and consider any potential obstacles or space limitations. You will need to ensure that the tank you choose can fit in the available space and that there is enough room for any associated plumbing components. Keep in mind that tanks are designed for a range of common positions in a van; for instance, some are grooved to fit underneath the van, others are shaped to fit around the wheel well, many are perfect rectangles, and some can even be custom designed to fit your exact measurements.
Water Usage
Consider the amount of water you plan to use for activities such as cooking, cleaning, and showering. This will impact the size of the water tank you need. You can estimate your water usage by calculating the average amount of water you use per day and multiplying that by the number of days you plan to be on the road between refills. There are a few calculators out there to help you, but these probably aren’t necessary and aren’t incredibly effective without gauging your personal use scenario anyways (be honest with yourself). How long will you shower, and how often? What about cleaning, cooking and drinking water? For context, showering is roughly 2.5 gallons per minute (gpm) per person, but you can cut this down by turning the water off while scrubbing, and generally using sparingly. Cleaning dishes uses 2-5gpm, while most people drink at least half a gallon per day.
Number of People
The number of people who will be using the water system will impact the size of the water tank. If you have a larger family or group, you will need a larger tank to accommodate everyone's needs. You should also consider the size of your van and how much space you have available to install a larger tank. This factor should be considered in parallel with the unique estimations for each individual for water use as described above.
Use and type of water
Consider the type of water you plan to store in the tank; effectively, are you using this for freshwater, gray water or black water? If you plan to drink the water, you may want to consider a tank that is specifically designed for drinking water. Some tanks are made of materials that are not suitable for storing drinking water, so it's important to choose a tank that is safe for this purpose. You may also want to consider installing a water filtration system to ensure that the water you drink is clean and safe.
Durability
The durability of the tank is important, especially if you plan to take your van off-road or do a lot of rough camping. A tank that is prone to punctures or leaks could quickly become a major problem. Look for a tank that is made of high-quality materials and is designed to withstand the rigors of van life. You may also want to consider a tank with additional features such as a protective cover or insulation to prevent damage from extreme temperatures. Your needs for durability will also depend on where you decide to install this tank; if it’s going to be put underneath the van, durability is a serious factor.
Installation
Consider the ease of installation and whether or not you will be able to do it yourself. Most tanks that we see in custom vans are designed to be easy to install and can be done without professional help, while others may require more advanced plumbing skills. If you are not comfortable with DIY installation, you may need to factor in the cost of hiring a professional to do the work for you. Also consider where you’ll install this tank - as it may dictate the particular shape you choose. Importantly, consider whether you want to buy a tank with pre-established spouts, vents, and plumbing fittings, or if you’ll plan to cut / append them yourself.
Convenience
How often are you comfortable re-filling your water? If you expect this to be a burdensome chore, or you plan to go incredibly far off-grid, without frequent access to water fill-up, then you may want to enhance your tank capacity.
Maintenance
Some types of water tanks require more maintenance than others, so it's important to consider how much time and effort you are willing to put into maintaining the system. If your purposes for the tank require frequent cleaning and maintenance, then look for a tank that is accessible, with features such as removable lids or access panels for easy cleaning. You should also consider any additional maintenance requirements such as replacing filters or treating the water with chemicals to prevent bacterial growth, although most of the standard tanks used in custom vans aren’t this complex.
Cost
The cost of the water tank and associated plumbing components should also be taken into consideration, as some systems can be quite expensive. You should look for a tank that fits within your budget while still meeting your needs. Keep in mind that investing in a high-quality water tank can save you money in the long run by preventing costly repairs or replacements. Tanks can range from $25 to well over $500 depending on sizing, material and any unique / custom measurements.