When we say we specialize in ADUs on septic, we mean we start in the dirt, not on Pinterest.
Upfront feasibility instead of guesswork
We review your existing Title 5 report, as‑built plans, and bedroom count, and bring in a septic engineer when needed. If the system has to be upgraded, we price and phase that with the ADU from the very beginning, instead of pretending it’s “separate” work and surprising you later
Engineering and permitting under one roof
We coordinate with your septic engineer, the Board of Health, and the building department so septic design, ADU plans, and permits all move together. You’re not stuck playing middleman between “the septic guys” and “the builder.”
Construction sequencing that actually works
We handle excavation, system replacement or upgrade, and the ADU build as one project. That keeps you out of the nightmare scenario where the ADU is finished, but you can’t legally occupy it because the septic sign‑off is stuck in limbo.
Bottom line: if your property is on septic, your ADU lives or dies on how well the dirt work is planned. That’s the part we’ve been doing for years; the ADU is just the structure that sits on top of it.
Custom ADU Builder for South Shore Properties
Built with Local Expertise. Managed from Concept to Completion.
Before you choose a floor plan, know what your property can actually support. Amex evaluates access, grading, drainage, utilities, septic, setbacks, foundation needs, and build options before the project moves forward.
Amex Construction helps Families expand, upgrade, and build with confidence.
Building an ADU in Massachusetts isn’t about picking from a catalog—it’s about creating a living space that fits Your Family and Property. From site prep and foundations to finishes and energy efficiency, Amex Construction builds ADU’s that are durable, beautiful, and uniquely yours.
At Amex we have a simple 4 step process to ADU’s
Step 1- Feasibility & Utility Review
Step 2- Preconstruction, Design & Permitting
Step 3- Site work & Construction
Step 4- Final Inspection & Move in