How Do You Design an ADU So an Adult Child Does Not Feel Like They Are Living in Their Parents' Yard?

By Buz Artiano, BuildX | September 2026

Watch: The Creighton Family Built an ADU in 98 Days, Here's the Full Story

You floated the idea and your adult child wouldn't go for it. Not because of money or how much time it would take, but because they just don't want to live in their parents' back yard. That objection has to do with who they are and the level of privacy they want, it's not about construction or size or price or any of that. The question here gets answered with carefully planned design decisions that have to be made before the plan is chosen and drawn.

My name is Buz Artiano, founder of BuildX. We've built dozens of ADUs all over Massachusetts, but most of our jobs have been on the South Shore and in Plymouth County. We do everything from design to permitting to construction ourselves. Privacy on a shared lot is dictated by the same things that dictate everything else. Those things are septic capacity, lot coverage, and the town's setback requirements. Those things are what control what you can build on your lot. We make sure all that stuff gets locked in early in a project. So does the answer to your daughter's objection.

Terry and Kevin Creighton are BuildX clients. We built a 900 square foot ADU above a garage on their property in Plymouth for their daughter Abby and her partner Raya. Terry brought up the idea first, and Abby objected because of privacy and other reasons. This is what Terry said about that moment "So you had brought up the idea of an ADU and Abby was like, there is no way I'm doing that." But Abby actually lives there now.

Obviously we want to share stories from families who had a good experience with us, but we are sharing this one for a reason. Abby started out hating the idea and now she can tell you exactly why she changed her mind, which is worth more to you than anything we could say about ourselves.

What Makes an ADU Feel Like Its Own House?

Three things help make an ADU feel like its own home. Separation, orientation, and approach. It's based on how much space is between the two homes, which doors and windows face the main house, and whether the person living there has access to their own door without crossing their parents' space. Abby Creighton told us herself "That was my primary concern was I want a house that feels like it's mine. I don't want to feel like I'm living in my parents' yard, even though I am." The goal isn't to hide the main house. It's to keep the ADU from feeling like it's just an extension of it.

Two months after move-in, she gave us her description: "When we're in the ADU, I can forget that the main house is there." That's the comparison you want to use in situations like this. Her opinion had nothing to do with square footage. It depends on where the building sits, which way it faces, and how you get to it.

Four decisions gave us that outcome, and each one was the answer to an objection. Think of these next four things as separate rather than one privacy preference as a whole. Each one of these decisions are settled at different times by different people. The distance between the two buildings is up to the town and your lot. The direction the home faces is settled at the drawing stage. The approach is decided by how the driveway can enter. Sightlines are settled by what is already on the property.

How Far Should My ADU Sit From the Main House?

On the Creighton lot the two buildings are about 20 to 22 feet apart. That's not an exact measurement, it's an estimate from memory, and Terry Creighton says that she never measured it, so it's definitely an approximation. But the effect is very real. When we viewed our finished project, that 20 foot separation is what made it feel like its own house. The unit is right there on the lot, but it still looks like its own separate home.

We build detached ADUs a lot more often than attached ones. That's not because of the number of feet, it's because a detached unit has its own roofline, its own separate shell, and its own front door. There are no shared walls for sound to travel through, or to make the second home feel like an addition to the main house. When the ADU is its own building, 20 feet of separation feels about the same as 40 for the person living there, because regardless of how big the gap is, it still feels like its own place. That's why we don't treat separation as something that can be sacrificed when money gets tight. On a smaller lot we would rather make the ADU a little smaller than make it attached to the main house.

The distance is not entirely up to you unfortunately. Massachusetts allows one ADU by right on a single-family lot under the Affordable Homes Act, and the town's specific requirements like setbacks, building code, and health code still apply on top of that. Those local dimensional requirements are what set the outer boundary of where a second building can go on the lot. You can see all the state requirements at mass.gov. Your separation distance is whatever the buildable area leaves you. However orientation is something you can control.

Flipping the Plan So Only One Door Faces the Main House

The thing that had the most effect on this whole project didn't cost anything because we did it at the drawing phase. We just flipped the floor plan. Terry Creighton said "there's only the one door." The flipped plan left a single door and a single window on the wall facing the main house. All the rest of them point somewhere else.

What Abby said about what she sees out those other windows is the other part of it. She said "we're seeing like our neighbors in the woods and we like really don't see their house at all. So it does feel very private." The family hung curtains on the one exposed side. That's the only money they had to spend for privacy on a 900 square foot home.

Orientation can be changed for free while the plan is still on the screen, but it does get expensive once you're past that phase. Moving a door to the opposite side of the house after a set is drawn, priced, and permitted means having to redraw the whole thing. Redrawing means that framing and mechanicals also fall behind on schedule. So we settle which side faces the main house at the time as the bedroom count and square footage, before anything is priced. People usually show up knowing how many bedrooms and what size they want. The question we then ask them is about which windows the person living here will look out of every morning.

Do I Need a Separate Driveway for the ADU?

Abby Creighton says a separate driveway was one of the things that made the biggest difference. "We have like our own separate driveway too. So that helps." When you're pulling onto the property, that's usually the moment that a person decides whether the setup really works or not. If the occupant has to pull past the main house, park in a shared spot, and walk through their parents' space to get to their own door, it makes them feel like they are lower on the totem pole. But a good design can fix that.

A second driveway isn't always possible on every lot. Frontage, grade, and the location of the buildable area are what will determine that. If a second driveway can't be built, the next best thing is a dedicated parking area with a walkway that reaches the ADU door without passing the main entry. It's not about the second driveway itself. It's about having a fully independent way to enter the ADU. And that belongs on the site plan next to the home, not in a landscaping conversation down the road.

Whose Objection Am I Actually Designing For?

A lot of time the person who wants to build the ADU is not the one who will be living in it, and the design requirements need to come from the person who will be living there. On this project the parents wanted to build the ADU, but their daughter, who would be living in it, didn't. Terry said "Once we got Abby and Raya on board, I knew, I knew Raya wasn't going to be hard, but Abby was the tough one."

The two occupants had different objections. Raya actually committed after one walkthrough, but Abby needed the separation questions answered specifically before she would even consider it. If you're building an ADU for an adult child and their partner, ask each of them individually what would make it feel like theirs. Expect to get different answers from both of them. Then put both their answers right into the plan, because the drawing is where you put it on paper, so you make sure your privacy concerns are addressed all the way through construction.

The parents had different questions, very legitimate ones. Terry Creighton said "I also was concerned about how would the dynamics change in the family. And would it be weird to have that? I didn't think it would and it hasn't been, but it did cross my mind a few times." Both sides are going to have some worry, but only one of them is being asked to move.

Why Walking a Finished ADU Changes the Answer

Abby Creighton's objection came down to a walkthrough. "When we saw the home tour in Plymouth, I was so impressed by how much it really felt like its own space and there was clearly privacy between the ADU and the main home. And that kind of got me on board a little bit with the idea."

She also said "these aren't just random plans. We know what this looks like." A floor plan makes you have to imagine what the level of privacy would be, but touring a finished unit shows you in real life. Raya's reaction to the same tour was immediate, Abby told us "as soon as she saw that home tour, she was like, I'm in, like no hesitation," and then, "as soon as she left, she called me and she was like, we're building an ADU. We have to do this."

If someone in your family is the holdout, walking a finished unit is what will change their mind, and that's who needs to see an ADU, not the family member who's already convinced. Send them in with the questions they won't ask. How far is this from the main house? What is visible through the kitchen window? Where do I park?

When Is a Backyard ADU the Wrong Answer for My Family?

A good design usually answers most things, but it can't answer relationship questions. Terry Creighton put it more bluntly than we would: "Adults are not designed to live with your parents." The four decisions we talked about are there so that adults aren't living with their parents. They are living near them, in their own separate home. If you don't have the kind of relationship where you can be close to each other like that, then no amount of separation on a drawing is going to fix that.

That is why the family conversation always comes before we even talk about design. Abby Creighton's advice to other households is to have that conversation first: "you have to have a conversation first with your family to figure out." Our own version, after enough of these builds, is that family dynamics ends up being about 70 percent of a build. We would rather hear a hard answer at the very beginning than discover it once we've already started building.

Detached is also not what we always automatically recommend. There are reasons to connect an ADU to the main house, and we build attached units when it's the right thing for the situation. If your household needs the two homes joined, say so at the first meeting, because the privacy strategy for an attached unit is a different set of decisions than the four described above.

What to Settle Before Your Plan Set Is Drawn

The four decisions that answered Abby Creighton's objection were all made before anything was priced: separation, orientation, approach, and sightlines. None of them were upgrades. They were requirements, set by the person who was going to live there and written into the drawing instead of promised in a conversation.

If your adult child has already told you no, that answer is reversible. Get them to the walkthrough, then get their requirements into the plan.