Woburn adopted a conforming ADU ordinance in May 2025 that bars the City from requiring any discretionary approval — no special permit, no site plan review, building permit only. It is also the only town in the region that provides for a second ADU on the same lot.
Zoning Ordinance Section 35, “Protected Use Accessory Dwelling Units,” was adopted 27 May 2025. As a city ordinance it needed only City Council passage and the mayor’s signature — Attorney General review applies to town bylaws, not city ordinances.
The size cap restates the state rule without enlarging it: half the gross floor area of the principal dwelling or 900 square feet, whichever is smaller.
Attached and detached units are both by right in R-1, R-2, R-3, R-4 and S-1. Attached units are additionally allowed by right in every district where the primary structure is pre-existing nonconforming — a genuinely useful provision if your house predates the current zoning.
The ordinance expressly bars the City from requiring a special permit, waiver, variance or other discretionary zoning approval, and there is no site plan review.
Woburn is the only one of the eleven towns we track whose ordinance provides for a second ADU on a lot, by special permit from the Board of Appeals, to a maximum of two per lot. The first is by right; the second is discretionary. On the right property that is a materially different proposition from anywhere else in the region.
Sewered citywide as an MWRA community, with partially supplied MWRA water. Septic is effectively a non-issue.
The cost to plan for is connection rather than capacity. Residential connection runs $500 per equivalent unit per utility, with a $500 minimum — one unit equals three bedrooms, 330 gallons per day or 4,400 square feet, calculated in thirds with a minimum equivalency of one. A typical ADU is therefore $500 for water and $500 for sewer at minimum.
There is also a mandatory inflow and infiltration mitigation fee on a building sewer permit. We have not been able to confirm the amount, and it can run to four figures — ask before you budget.
Stretch Code effective 1 January 2012, confirmed locally in the Municipal Code. Specialized Code not adopted. HERS rater targeting 52–58 with the existing house excluded, a 50-amp EV-ready circuit per dwelling unit within six feet of a parking space, and a solar-ready zone of at least 300 square feet on a qualifying new detached unit.
$15 per $1,000 of estimated construction value with a $50 minimum — the most expensive building permit rate of the eleven towns we have checked. Re-roofing and mechanical run at the same rate. Electrical for a new dwelling is $150 per unit; a partial remodel or addition is $50. Plumbing is $50 for the first fixture and $10 each additional, and gas is the same. Demolition is $15 per $1,000 with a $50 residential minimum.
Filing is fully digital through CitizenServe. Residential submissions need a site plan with a surveyor or engineer stamp where required, floor plans, exterior elevations, cross sections and details, foundation plans, framing plans and specifications, at a maximum sheet size of 11 by 17 — two paper sets, or one paper set plus a PDF.
We would rather show you the gap than fill it with a guess. Confirm anything below with the town before you rely on it.
The inflow and infiltration mitigation fee amount — mandatory on every new dwelling unit, and the one number here we most want and do not have. The operative text of §7 on nonconforming uses. Whether any isolated unsewered parcels exist. Whether a residential addition triggers Groundwater Protection District review under §15. Plan review turnaround. The per-additional-unit dimensional rows for R-3, R-4 and S-1.
We build accessory dwelling units across the Merrimack Valley — supervised by Matthew Moisan under Massachusetts Construction Supervisor License CS-119855 — and we carry the permit set, the site plan review and the inspections. Tell us the address and we will tell you what the lot actually allows.