Studio 160 starting price, plus installation and property-specific scope.
Massachusetts ADU cost guide · 2026
A clear ADU budget starts with the property.
See the current Lumara starting point, the early professional-service allowances, and the property-specific work that turns a model price into a responsible project budget.
Early planning allowance. Authorized separately when the project is ready to proceed.
Architectural and structural planning estimate—not included in the survey authorization.
The cost stack
One project. Four different kinds of cost.
A model price alone cannot describe a buildable Massachusetts ADU. Lumara separates the home, professional services, site work, and utilities so each decision stays visible.
The ADU
The selected steel structure, building systems, windows, fixtures, code package, and interior finish direction.
Professional services
Survey, architectural drawings, structural engineering, energy/code coordination, and permit-ready documentation as required.
Site + installation
Delivery access, foundation, excavation, grading, drainage, crane or set conditions, restoration, and other lot-specific work.
Utilities + approvals
Electric, water, sewer or septic routes; capacity upgrades; permit fees; inspections; and requirements identified during local review.
Decision gates
Spend in sequence—not all at once.
The purpose of feasibility is to avoid committing to full design or construction before the property, delivery route, utility path, and likely permit approach make sense.
Property review
Address, likely placement, setbacks, access, utilities, and major constraints.
Survey
Existing conditions and property information needed to advance planning.
Plans
Architectural and structural work begins only after scope and authorization are clear.
Build scope
Model, site work, utilities, installation, schedule, and contract are finalized.
What the figures mean
Allowance, estimate, and contract price are not interchangeable.
Clear labels protect the homeowner and the project team. Each figure becomes more precise as the property and technical scope become known.
LabelCurrent exampleMeaning
Starting price$120,000 Studio 160A model entry point. It is not a universal installed price for every property.
Allowance$3,000 surveyA planning amount reserved for an identified scope; reconciled to the actual service and written terms.
Estimate$20,000 plansAn early budget expectation for architectural and structural work, refined before authorization.
Contract priceProject-specificThe agreed price for a defined scope after the site, selections, exclusions, and responsibilities are documented.
Important: The figures on this page are current planning references, not an offer or final construction quote. Property conditions, design, utility capacity, permitting, material selections, and third-party requirements can change the total.
Cost questions
The useful answer is specific to the lot.
These are the questions Lumara resolves before recommending a configuration or next paid step.
What is included in the $120,000 starting price?
The $120,000 figure is the current Studio 160 starting point. Final inclusions are confirmed after the property review and written scope. Site access, foundation conditions, utility routes, permitting, and selected finishes can affect the installed project price.
Is the $3,000 survey fee part of the $20,000 plans estimate?
No. The survey allowance and the architectural/structural plans estimate are shown as separate phases. The survey can be authorized first; plans should not begin until the homeowner approves that next step in writing.
Why can’t Lumara give one installed price for every property?
Two identical ADUs can require very different foundations, access plans, utility runs, drainage work, septic coordination, or electrical upgrades. A property review identifies those variables before they become surprises.
What can increase the site-work cost?
Long utility runs, limited delivery access, ledge, slopes, drainage conditions, tree work, electrical capacity, septic requirements, difficult excavation, and restoration needs are common cost drivers.
When does construction pricing become reliable?
Pricing becomes substantially more reliable after the property review, survey, selected model, utility strategy, permit path, and design scope are known. Lumara can then organize a defined project scope and exclusions.
Start with the lot
Turn a starting price into a property-specific plan.
Share the Massachusetts address. Lumara will review likely fit, access, utilities, placement, and the next responsible step.