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Bob Christian, our resident build expert, has had a lot of questions regarding plumbing and water equipment he’s used in builds, so he’s compiled a list of products he’s used in the past and recommends. He also includes information and addresses issues faced in the past during installs.

He’s had a fair amount of inquiries and has read posts concerning sinks for trailers. The questions usually center around what size, how much water, how many sinks, etc. The only person who can answer those types of questions is you, or if you’re going to be permitted, your local health department. If you’re going to be bound by the health department regulations, then ask for the requirements which generally require the following:

  • A three-compartment sink, with a drying rack to the side.
  • A hand washing sink
  • A specific amount of freshwater (i.e. 25 gallons)
  • A grey water tank that is bigger than the size of the fresh water tank
  • A hot water heater which will specify either a temperature or size requirement.
  • Food grade fill hoses
  • Wash out port for grey water tank
  • The ability to completely drain both the grey water and fresh water tanks

This is not an all-inclusive list. There have been instances where the client (because they were
not a “food truck”) was able to negotiate the size of certain items of the requirements. This is a
lot of equipment that takes up a fair amount of space, power, and hard-earned cash.
Can it be done? Yes! Check out the photo below. But you need to know beforehand which
direction you want to or have to go.

If you’re not going to be permitted by a health department, what will you use the sink for?
Hand washing? Rinsing bar items? Washing items? Once you decide on the purpose you can
narrow down the size of equipment (sink, tank, water pump, faucet). A simple hand washing
sink can use as little as 5 gallons of water, and have a foot pump saving weight, money, and

There are also some very important things to consider. Can your trailer and tow vehicle handle
the addition of the weight involved with the additional equipment and water? A full 50-gallon
water tank weighs in the area of 350 lb. Add another 35 lbs for a full 5-gallon water heater and
you have substantially increased the weight in your trailer (and this doesn’t include the weight
of the stainless-steel equipment in the trailer).

But wait! Isn’t it an old horse trailer that can take the weight? You’re right… if it’s in the right area of the trailer. Depending on the tow vehicle, putting 350 lbs (or more) in the nose of a horse trailer or camper can come dangerously close to exceeding your hitch capacity. Putting all the weight in the rear of a trailer can cause the tow vehicle to lose traction in the rear.

This equipment in particular was used in a coffee trailer build. The grey water tank is on the opposite side of the freshwater tank and is under the three compartment sink. It can be pared down as needed, if you only need a hand washing sink or something similar.

This sink was picked because code required the walls on the sides of the since because we were mounting it inside a countertop. It is NSF certified, and I recommend leaving that label on it for the health department to see. It came with the faucet and was a straightforward installation.

We bought the combo pack of water tanks for grey and potable water. The grey tank must almost always be bigger than the water tank and have a wash out port. These tanks do not have that wash out port, so I added one which is shown below. We were able to mount the grey water tank under the three-compartment sink which saved a lot of room. The tanks do not come with any of the fittings or straps to hold them down. 

This is not mandatory but a good idea if you are using the water for more than cleaning and hand washing.

Just another example of a tank I considered. My choice came down to where the fittings were located based on my plan for everything.

Because we were using the system for hand washing and hot water it needed to be self-priming, pressure activated, and supply the water needed (GPM) for the hot water tank we used. This pump, like most, will require a separate in-line fuse which can be found on amazon as well.

This was use with the three-compartment sink. The installation was straight forward.

If you’re going to fill the water tank from the outside this kit is what you would use. You drill through the side of the trailer and it connects to the inlet of the water tank.

This was the sink we used and we based the size on what was required by the health department in NY. It generally has to be able to fit anything you intend to wash during operations. Some locations require a rack on the side of the sink as well. 

This was the sink we used and we based the size on what was required by the health department in NY. It This was the hatch cover we installed on the grey water tank so it could be cleaned out as required by the regulations. 

We used this hot water heater. It runs on 110v and after installation the water was measured at 165 degrees (155 degrees was required by code). The tanks come in different sizes, but we went with the biggest (measurement-wise) that we could fit inside the space we had picked out.

We used these straps to hold the tanks to the floor. Because both tanks have to be mounted on a slant so they can be completely drained, we built wooden frames to hold them on a slant as well as in place. These were then used to hold them inside the frame. 

All the plumbing fittings were purchased at Home Depot. We used approximately 20ft of PEX and PEX fittings for all the water lines as they are very forgiving in a trailer environment (moving, heat, etc). All the fittings, PEX and PEX fittings were around $300.00.  You can see pictures on how we mounted everything at

This is just a very brief overview of what will be needed for a permitted trailer. Remember that the regulations swing wildly from somewhat lax to very restrictive. Due diligence in this area will save you a lot of heartache, money and time if you know beforehand what is required. If you’re not going to be permitted you can install almost anything in your trailer, but doing things correctly the first time will pay off in the long run, in less aggravation, and money, if you ever flip your trailer.

If you have any questions feel free to contact me at