Off-Grid Living in Londonderry, New Hampshire

I've been digging into what it actually takes to live off-grid in Londonderry, New Hampshire, and the short version is: this is a zoned town, not open country, so almost everything you want to do with raw land or an alternative dwelling runs through the Town's Zoning Ordinance and Building Department, layered on top of state rules.

Zoning. Londonderry has had a formal Zoning Ordinance since 1963, administered by the Town's Planning & Economic Development Department and enforced through Building & Zoning Enforcement. Land use is organized into base districts like AR-I, R-III, and C-III, plus overlay districts (for example, the Route 102 Performance Overlay and an Airport Approach overlay), and every use has to fit into a Table of Uses for whatever district a parcel sits in. There's no general allowance for just occupying raw land in a tent or camper outside of what's enumerated. If you're eyeing a specific parcel, calling the town's zoning administrator to ask "what can I do here" before buying is worth it.

Dwellings and ADUs. The town does have a right-by-district accessory dwelling unit rule: one internal, attached, or detached ADU is allowed by right on a lot with an owner-occupied single-family home. I did not find anything in the research addressing tiny houses on wheels or RVs used as a standalone, permanent residence, so I'd call that unconfirmed and worth a direct question to the Building Department.

Building codes. Londonderry enforces state-adopted building codes locally, with the 2021 I-Codes set to take effect January 1, 2025. This is a state-mandated framework (RSA 155-A) that the town's own Building Department administers and inspects, meaning permits and inspections happen at the town level even though the code itself comes from the state.

Septic and composting toilets. Septic systems are a state matter, regulated by NH DES under its Env-Wq 1000 rules; DES reviews and approves system design before the town gets involved. Privies, meaning non-water-carriage outhouses, are permitted under the state framework for sites without electricity or running water, but they need sign-off from the local health official on siting and construction, so Londonderry's town government still has a hand in it even though the underlying authority is the state.

Greywater, rainwater, and wells. I could not find a Londonderry-specific ordinance on greywater reuse or rainwater harvesting, and no town-specific well ordinance either. Wells fall under the state's Water Well Board framework by default. Treat all three as unconfirmed at the town level and confirm directly with the town and with NH DES.

Utility disconnection. I didn't find an explicit "must hook up to utilities" ordinance, but living off-grid successfully here really comes down to whether your dwelling and septic setup pass the Building Department's permitting and occupancy process, since that's the practical checkpoint.

Bottom line: Londonderry isn't hostile to off-grid features like composting toilets or ADUs, but it is a fully zoned, code-enforcing town, and the town + state layer both matter.