Are Composting Toilets Allowed in Massachusetts?

Composting toilets and greywater systems can be a great solution for how to deal with waste water.  But are you allowed to use them on your own land in MA?

Spoiler alert: Like pretty much every code, there’s not a single easy answer that applies everywhere.

According to mass.gov, for residential homes: “Title 5 (310 CMR 15.000) allows composting toilets for Remedial Use and also certifies them for General Use in new residential construction where a system in full compliance with Title 5 could otherwise be installed. The local approving authority (typically the Board of Health) must also approve installation of a composting toilet through a Disposal System Construction Permit and Certificate of Compliance. Check with your local Board of Health for its approval procedures.”

Read all the details here:

Source: https://www.mass.gov/files/documents/2016/08/qm/comptoi.pdf

Note that this doesn’t apply to tiny houses on wheels– only homes that are permanently affixed.

In summary, Title 5 allows for conforming composting toilets and a greywater system in new residential construction where there could otherwise be a septic system.  However, this doesn’t mean it’s allowed in every town.  The local Board of Health will also have to approve it. 

Here’s how to get in touch with your local Board of Health in Massachusetts.

But wait: a composting toilet isn’t the only option for your tiny house!

B&B offers five different toilets for tiny houses on wheels: the best solution for you depends on where you’re parking your tiny house, whether it’ll move, what utilities are available and how often you’ll use your tiny house.  Check out this blog post on the 5 Types Of Tiny House Toilets.