Built for comfort and longevity.

Flexible Living Space

Add space, value, and options

An Accessory Dwelling Unit (ADU) is one of the most flexible ways to expand your living space and add long-term value to your property. Whether you're building a detached backyard cottage, converting your garage, or turning a basement into a complete living space, Biviano GC handles the entire process—from planning and permits to construction and finishing details. With decades of local experience and a strong reputation across Marshfield, Duxbury, and the South Shore, we build ADUs that are safe, comfortable, code-compliant, and designed to meet your exact goals—whether it's rental income, family housing, or a private guest suite.