Step one: find out if your lot qualifies
Before anyone talks dates, we confirm the project is real. The free property and zoning review checks your parcel against New Hampshire's by-right ADU law (RSA 674:71–73), your town's setbacks, and anything that could complicate a build. No cost, no obligation, and no time wasted designing a home that can't be permitted.
If it's a green light, the next step is a $250 on-site assessment — credited straight back toward your build. We walk the property and look at where your utilities and septic run, soil and ledge, equipment access, grade, and exactly where the ADU sits best. This visit is what keeps the later phases from stretching: the surprises that blow up a schedule are the ones nobody looked for.
Design and your all-in price
We match you to one of our architect-designed models — or work from a custom design of your own — and tailor it to your site and budget. Pick a pre-priced plan as-is and there's no design fee at this step. Custom plans start at $1,500, credited toward your build up to $2,500. Either way, you leave with a fixed, all-in price. How long this phase takes is mostly up to you — homeowners who know what they want move through it quickly; the ones weighing custom changes take longer, and that's fine.
Permitting: paperwork, not hearings
Since July 1, 2025, RSA 674:71–73 (HB 577) allows one ADU by-right on every single-family lot in the state. By-right means a compliant unit doesn't face a discretionary hearing — no pleading your case to a board, no waiting on a variance. That removes the single biggest delay in old-style ADU projects. Here's the plain-English breakdown of the law.
It does not mean instant paperwork. Every town still runs its own queue, and some only meet monthly. We prepare and file the applications, handle the town paperwork, and coordinate every approval through to your building permit — but we won't pretend to control the town's calendar, and neither can anyone else.
The build: 12–16 weeks, same calendar every time
Permit in hand, we break ground, and from here the schedule is ours to keep. Weeks 1–3: sitework and foundation — clearing, excavation, the foundation poured to spec, and water, sewer, electric, and data trenched from your house to the new pad. Weeks 4–7: your ADU is set on the foundation, the roof tied in, the exterior weather-sealed, utilities connected. From the outside it looks done.
Weeks 8–13 are interior finish: electrical and plumbing finished out, flooring, fixtures, cabinets, paint, appliances. Weeks 14–16: town final inspection, Certificate of Occupancy, and keys. The week-by-week build page lays out the whole calendar.
What stretches a timeline — and what doesn't
Three things push a build toward 16 weeks instead of 12: wetland or shoreland buffer review by the town, ledge or septic issues discovered after the site visit, and towns that run their permits or inspections on a monthly schedule. We surface all three at the site visit, so you know which end of the range you're signing up for before you sign anything.
What doesn't stretch it: the model itself. A smaller model on a clean, ready lot lands near 12 weeks; a flagship two-bed on a trickier site lands near 16. The sequence never changes — only how long the site makes each step.
Walkthrough and keys
The last step is the town's final inspection and your Certificate of Occupancy, then a walkthrough with you for any punch-list items. Keys in hand, you can have a tenant moved in by the end of that week. The full phase-by-phase path — from the first free review to that walkthrough — is on our process page.