A 900 Square Foot Marshfield ADU, Built for Christina

Why did the Copelands build an ADU in Marshfield?

Alice and Dean Copeland's daughter, Christina, was ready for her own home. She also lives with autoimmune conditions that make an ordinary home a real problem: unknown neighbors, unknown materials, and nobody close by if she needs help. The family looked at a condominium and thought about an apartment, and neither answered the actual question, which was how Christina could be independent and still be thirty feet from her parents.

An ADU in the backyard answered it exactly. As Alice put it, it is the way it is supposed to be: your kids grow up and move on. This one just moved somewhere she could watch being built from her window.

How was this ADU designed around off-gassing concerns?

The family raised it at the very first meeting: materials that off-gas were not going to work for Christina. Buz did not just agree and move on. He went and did his own research, then called back with options the Copelands had never heard of.

Particle board came out of the plan entirely. Adhesives were minimized throughout the build, with natural pine boards used to cut off-gassing further. The insulation is mineral wool, resistant to mold and mildew. The paints are low-VOC. The unit was also engineered with a whole-house ERV system to keep fresh air moving continuously rather than trapping it.

That sentence is why the Copelands hired BuildX. Most builders, Alice says, want to get the job done, make their money, and move on. This one was researching insulation for a young woman he had just met.

What was construction like for the Copeland family?

Somebody was on site at seven o'clock every working day. Justin, the project manager, gave the family daily updates on who would be there and introduced the crews as they arrived; if he was not on site, he called. The subcontractors were polite, fast, and cleaned up after themselves.

Alice works in the industry and hears from customers who have not seen their builder in two weeks. Here, she watched the hole get dug, the concrete poured, and the framing go up, with visible progress every single day. “She gets to look out the window and see it being built,” Dean says of Christina, “and say, that's my house being built.”

How long did the Marshfield ADU take to build?

Buz committed to 100 days of construction at that first kitchen table meeting. The build came in under it, first shovel to finished home, in the year it was started. The commitment was the ceiling, not the estimate.

Does 900 square feet feel small?

Not in this house. Nine foot ceilings and taller windows fill the rooms with light, and the reaction from people touring it became a refrain: “I can't believe this is 900 square feet.”

What changed once Christina moved in?

Christina lives there now. She pays her own bills, takes out her own trash, and controls her own space, in a home where every material was chosen for her. “Everything about this ADU, the low VOC, the low adhesives, the off-gassing, everything is built for her,” Dean says. “She's had no issues since she's moved in.”

Alice and Dean got something back too: their own independence as a couple, with their daughter still right there. On the last day of the open house, Alice hugged Buz, because it felt like a friend was moving on to his next project. Her review of the company runs two words: “Phenomenal company.”

Can an ADU be built for someone with health or chemical sensitivities?

Yes, and this is the build that proves it. It was engineered around off-gassing from the first meeting rather than adjusted for it later: no particle board, minimized adhesives, natural pine boards, mineral wool insulation, low-VOC paints and a whole-house ERV, all chosen around one resident's specific medical needs. If someone in your family has autoimmune, respiratory or chemical sensitivities, raise it on the first call. It changes the specification, not the schedule.

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