Andover, Massachusetts • ADU Service double‑click

Build an ADU in Andover — by right double‑click for more

Massachusetts now allows a single ADU by‑right in single‑family zones. Max size is the smaller of 900 sq ft or ½ of your home’s GFA. Near the train (½‑mile), towns can’t require extra parking. We handle feasibility, permits, plans, build‑out, and (optional) lease‑up. double‑click

Request 48‑hour feasibility — $1,500, credited to build double‑click Not legal advice; we confirm specifics with the Town and Board of Health.

Typical ADU budgets and rents vary — run your quick ROI math below.

What you get

ADU ROI — quick calculator

Enter a rent and a rough budget to see back‑of‑the‑envelope results. Estimates only; not financial or tax advice. Andover ADUs are for long‑term rental or family use (no STRs).

Tip: Hold Alt and double‑click any field label to load “Verified” explanations with sources (e.g., how to think about rent comps or interest assumptions).

Scenario Budget (est.) Rent (est.) Monthly net*
Garage conversion — studio/1‑bed $150k–$220k Owner input Use calculator
Detached 1‑bed (600–750 sf) $220k–$320k Owner input Use calculator

*Net after property management, maintenance/vacancy, and (if selected) debt service. Estimates only.

Eligibility in Andover — fast take

  • By‑right: One ADU allowed on lots with a single‑family home.
  • Size: ≤ 900 sq ft or ≤ ½ of the principal home’s GFA (whichever is smaller).
  • Parking: If any portion of the lot is within ½‑mile of a transit station, the Town cannot require extra parking. Otherwise, Andover’s local rule is up to 1 off‑street space unless Site Plan Review finds existing parking sufficient.
  • Use limits: Short‑term rentals are prohibited. ADUs cannot be condo‑split.
  • Owner‑occupancy: Not required under state law.

We’ll verify setbacks, historic/overlay districts, and any site‑specific constraints during feasibility.

Andover process — simple path

  • Site Plan Review using the Town’s ADU procedures (plan sheets, narratives, IDR/ZBA advisory review).
  • Apply via the Town’s OpenGov permit portal.
  • Title 5 (septic) pre‑screen: ADUs can trigger “new construction” design flow; two‑compartment tank or two tanks in series may be required on shared systems. We coordinate with your Board of Health.

On sewer? Permitting is usually more straightforward; on septic, we involve a Title 5 engineer up front.

Where parking relief applies (½‑mile)

If your lot is within roughly 0.5 miles of either commuter rail stop, the Town cannot require additional ADU parking under state regs:

Tip: In Google Maps, right‑click your property, choose “Measure distance,” and click the station to check the 0.5‑mile buffer.

Pricing

$1,500 feasibility (credited to build) • $8–12k permit‑ready plans • Developer/CM fee at build • Optional PM at standard rates.

We can package lender options that consider ADU rental income where program‑eligible.

Typical timelines

Feasibility (48 hours) → Plan set + application assembly → Site Plan Review submission → Building permit intake. Construction starts after permit issuance and GC contracting. Actual timing depends on completeness, reviews, and utilities.

FAQ

Can I rent the ADU short‑term? No — Andover prohibits ADUs from being used as short‑term rentals. Consider long‑term rental or family use.

Can I condo‑split the ADU? No — condo conversion of the ADU is not allowed under the local bylaw.

Do I have to live on site? No owner‑occupancy requirement under state law.

What about septic? Title 5 can require upgrades (e.g., two‑compartment tank) when adding bedrooms/design flow. We assess this first.

Official resources (helpful links)

Always verify your specific property with the Town and Board of Health. We’ll do this during feasibility.

Ready?

Get a written feasibility memo within 48 hours that covers zoning, Title 5, parking/transit, budget bands, and your permit path.

Request feasibility