A Complete Guide to Setting Up a Water System in a Tiny Home
By: Leah Neigum
Tiny houses can be a great way to conserve household water usage. It can be a lot of effort to get water in and out of these little off grid homes! This forces tiny house dwellers to be mindful of how much water they are using and to also be cognizant of where this water is coming from and going to. The world’s freshwater systems are facing increasing pressure due to pollution, growing populations, agriculture, increasing demand for energy and resources, and climate change (causing changes in precipitation, and increased frequency of droughts and flooding). Designing a water system for a tiny house while also keeping water conservation in mind requires some thinking and tinkering. I’ve put together some notes based on what I’ve learned from designing and building the water system for the Leahnardo tiny house.
Freshwater: An overview of the plumbing for the Leahnardo is as follows: ½ inch PEX, 146L water tank, Shurflo inline filters, a Shurflo water pump, a Valterra freshwater inlet port, a Marey tankless hot water heater, a little homemade hobbit tub/shower, a bathroom sink, and a kitchen sink. The Leahnardo has four separate sources of water supply: rainwater harvesting (from the roof), snowmelt filtration, freshwater tank (stored in the kitchen cupboard), and a water inlet supply line (hose that can connect to residential water supply to either fill the tank or bypass the tank in a permanent supply situation). All of these water supply sources are in essence, independent loops that can be isolated and turned on and off via in line ball valves.
Photos left to right: snowmelt filter, rainwater tower, Shurflo inline filter connected to rainwater tower.
A Note on the Homemade Tub/Shower: It is a rain barrel that I cased in cedar, tiled, painted with tub-and-tile paint with a drain drilled through it. It is space efficient and I can sit in it to have a bath, or I can also shower in it as well! When drawing my floor plan, I failed to think about if I would be able to find small RV style showers or tubs that would fit. Once I built the bathroom, I quickly found out that I couldn’t find any baths/showers that would be small enough to fit…so I had to build my own! On the bright side though, you can find some cute little soaker tubs here.
Photos left to right: kitchen sink, bathtub, bathtub with bathroom sink.
Tankless Hot Water Heaters: These little units are fantastic! They are extremely energy efficient in that they only heat the amount of water that you are using instantaneously. From my experience, they also use very little propane. The alternative (hot water tanks) can take up much more space in a tiny house. I have a Marey hot water heater that I got on eBay. It seems to be working great so far. My 2 cents though– buy your hot water heater from a local supplier. These units do take some tinkering/troubleshooting to set up and it would have been much easier if I had a supplier in Canada that I could communicate with. When purchasing a tankless hot water heater, it is also worth checking if a vent kit comes with the unit. If you have to buy the venting separately (typically B or Z vent) it can be expensive and sometimes difficult to come by if you are not a gasfitter. Check out some on demand hot water heaters here. Note: Hot water heaters have detailed clearances/venting regulations/codes. It’s worth thinking about where you are going to put this unit in the early stages of your planning/design of your floor plan for your house!
Leah in her kitchen with tankless hot water heater in back.
Greywater: I ran my shower pipe straight through the floor of the tiny house. I have a bucket under the house right now that catches the water, and I am recycling this water to use on the plants and trees-they don’t seem to mind it! It is important to note that soap can contain parabens and phthalates, fragrances and sodium laurel sulfate all of which can not only be harmful to your health, but can also be harmful to the environment. This is why it is important to use biodegradable soap! My kitchen sink drains through a course metal filter into a bucket in the kitchen cupboard. This way, I can reuse this water on the trees and the food particles won’t attract animals!
Blackwater: I don’t have blackwater because I use a compost toilet (and no…compost toilets do not stink!!) The toilet uses peat moss and a fan that runs off the solar panels 24/7. I have the Natures Head toilet. It does take some time to get over the social stigma of compost toilets, but when you really think about it -it does seem sensible to not use freshwater to flush away poo!
Leahnardo bathroom with Natures Head Compost Toilet.
“Water is the driving force of all nature”
– Leonardo da Vinci