Toilets and Tiny Houses

It seems inevitable that whenever a group of tiny house enthusiasts gets together, someone is going to bring up the topic of plumbing — and specifically toilets — pretty quickly. (One friend of Build Tiny may never live down the nickname Toilet Tim, thanks to his relentless questions about the merits of composting toilets at a workshop…) Your first conversation about tiny house toilets might feel a bit awkward, as you ask yourself how you jumped into such personal territory with people you’ve just met, but quickly you realize that the plumbing question is a very important one to consider when building a tiny house. Unlike a conventional house, where local building codes dictate many details of your household plumbing and restrict your choices to a very small number of decisions that are mostly aesthetic (PVC vs cast iron pipe, for example), a tiny house affords you a number of options when it comes to plumbing. The system you choose for dealing with human waste in a tiny house is determined by a number of factors; where you plan to park, whether any local codes affect your construction, your budget, and your willingness to interact with waste, chemicals, etc., all play a role in determining what toilet system best fits your tiny house. Here, we’ll consider the pros and cons of four different toilet options for tiny houses: traditional household toilets, RV-style toilets, chemical toilets, and composting toilets.

Traditional Household Plumbing

If your tiny house will be mostly stationary, with hookups to a sewer line or septic system, a conventional porcelain household toilet can be a fine option. You’re already (we hope!) familiar with the operation a standard flush toilet, so that’s one less lifestyle adjustment you’ll need to make if you’re downsizing from a larger house. The homes we craft at Build Tiny are sized to fit a full-sized household porcelain toilet, if the owner so desires.

  • Familiar operation for both residents and guests
  • Minimizes direct contact with human waste
  • May facilitate a tiny house’s compliance with local building codes*
  • Initial expenses include toilet and plumbing cost (from $150 to $500+) plus possible expert installation
  • Requires ongoing and continual access to a sewer or septic system for use
  • Uses significant quantities of water to flush and prevent odors
  • Additional expenses over time include sewage fees and/or septic tank maintenance

RV-Style Plumbing

If you’re planning to park your tiny house in RV campgrounds, or if you want to move with some frequency, an RV-style plumbing setup may fit your needs. Many RVs are equipped with holding tanks that capture and store black water (toilet waste) separate from gray water (from showers and sinks). RV toilets come in various sizes, but many models are sized to match full-sized household toilets.

  • Often uses less water than a traditional household toilet
  • Minimizes direct contact with human waste
  • Enables users to remain off-grid for days to months (depending on size of holding tank)
  • Requires access to pump-out facilities periodically to empty holding tank
  • Some plumbing is required to connect toilet with holding tank

Chemical Toilets

Chemical toilets, or port-a-potties, offer a self-contained option that requires no plumbing. Waste is captured and stored in a single unit, in which any of a number of chemical compounds is used to control odor and break down waste. Often these compounds have an artificial blue color, such as the water in an airplane lavatory. Once the unit is full, the waste is disposed either by the user or by a servicing company.

  • Minimizes water usage
  • Waste is broken down, controlling odor and reducing the volume for disposal
  • Self-contained units require no additional plumbing or holding tanks
  • Utilizes harsh chemicals, which users must handle when emptying unit
  • Some units may require expert servicing
  • Waste from some systems is toxic and requires specialty disposal

Composting Toilet

Composting toilets run the gamut from pricy electric units to simple, inexpensive DIY systems. These toilets use organic material, such as peat moss or wood shavings, to convert human waste into reusable organic compost. Many tiny house dwellers opt for composting toilets that can be custom-fit into small spaces.

  • Eco-friendly system utilizes only organic compounds
  • Easy to DIY
  • Requires no plumbing or additional storage tanks
  • DIY options are very inexpensive and simple – requiring as little as a five gallon bucket
  • Can be difficult to manage odors
  • May not be compliant with existing codes
  • Some commercial options require electricity for operation

What plumbing options are you considering for your tiny house? What have you done? Let us know in the comments!


*Build Tiny, LLC, cannot offer legal advice on zoning or code compliance. Check with your municipality for regulatory issues that may affect your construction.

See what a Build Tiny Workshop looks like!

Have you been interested in what one of our Build Tiny workshops look like? Take a peek!

Below is a video of our April 2014 Workshop in which you’ll see a tiny house built of SIPs (structural insulated panels), and a steel framed tiny chapel being built in a series of exciting time lapse videos!


To register for an upcoming workshop, contact Robin Hayes at 540-336-4478.

Dream Big, Build Tiny!

Build Tiny’s Stash

Being in the construction business for many years in the same area has it’s advantages. Today as I was running errands I came across another great deal. I needed some sheet copper for a table top so I went to my local Roof Center. After I purchased the copper I was chatting with the manager and asked him if he had many windows in the bone pile. Now he knows that I am always looking for a deal, so when he smiled and said “yeah, come on back”, I was pretty sure I was going to go home with a deal. Now shopping for tiny house windows is not quite the same as just grabbing any deal; I wanted to make sure they would be sizes that would be usable. They were. I left there with 8 windows.

So what am I going to do with all those windows you ask? Well I am going to add them to the growing pile of leftover, recycled, not needed, etc… stuff that I am sure someone will want for their tiny house.

This pile already includes a fridge, generator, power center and some other items I recently harvested from a camper that was heading to the recyclers. As well as building materials that are left over from jobs.

In the past these items have been donated to the Habitat Restore, and I still take some things there, but now I am going to set aside things for Build Tiny workshop attendees to purchase at super low prices, i.e. fridge $25, generator $50. At the beginning of each workshop I will let everyone know where the items are located and they can look through them. Options to purchase items will be determined by the order of sign up. First person to sign up for the workshop has first option to buy as much as they want. If they don’t want to buy everything, the second person to sign up has the next option….. and so on.

It will be nice if  all the stuff can find its way into a tiny house.

Upcoming Workshops 2014

Things have been busy around here lately. We have the roof completed on Derryl’s tiny Passive house and are rolling along with the roof on Bil’s tiny chapel. Next will be the doors and windows- and you can join us  and learn how to install high performance and irregularly shaped windows.

This workshop will be held on August 1 & 2. You may choose to attend one or both days.

The other workshop which has been scheduled is the big Fall Workshop.

Join us October 17-20 for the Build Tiny Fall Workshop.

We will be starting Amanda’s tiny house as well as working on closing in another tiny house.

We will have a live band on Saturday night, great food all weekend, and we always get a great group of people.

Come out and learn about building while you make new friends or reacquaint with old friends.