Best ADU For · 2026
Best ADU for Aging Parents: Which Model Wins
For most families housing one aging parent, the Six Sixty is the ADU to build. At 660 sq ft with one bedroom and one bathroom, it’s priced at $287,000 with a permitting budget already built in, delivers in about 5 months, and its single-level rectangle layout keeps everything, bedroom, bathroom, kitchen, within a few steps of the front door. If two parents are moving in together, or you want a second full bathroom for round-the-clock comfort, the Eight Eighty-Five 2/2 or the Nine Forty-Five 2/2 are worth the step up. Here’s how to tell which model actually fits your yard and your family.
The short version: For one aging parent, build the Six Sixty ($287,000, 660 sq ft, 1 bed/1 bath). It’s single-story, easy to navigate, and priced like a rental-grade ADU while still feeling like a real home. For two parents who each want their own space and their own bathroom, step up to the Eight Eighty-Five 2/2 ($402,000, 885 sq ft, 2 bed/2 bath) or the Nine Forty-Five 2/2 ($412,000, 945 sq ft, 2 bed/2 bath). If budget is the deciding factor, the Four Fifty studio ($180,000) still works for a parent who wants a small, simple footprint.
Why housing an aging parent needs a different kind of ADU
An ADU for a college kid or a short-term renter and an ADU for your mom or dad are not the same project, even though they can be the same square footage. A parent moving in usually needs everything on one level, which every Framework First model already delivers since none of them are built with stairs. But beyond that baseline, the details that matter shift: shorter distances between the bedroom, bathroom, and kitchen, a layout simple enough to navigate without a floor plan in hand, and enough separation from the main house that it still feels like their own home, not a spare room with a door.
Privacy cuts both ways here. Some parents want to be steps from the main house so family can check in easily. Others want a real front door, a real kitchen, and enough distance that visits feel like visits, not check-ins. The model you pick should match which version of that your family actually wants, not just how many square feet you can fit on the lot.
Budget and speed matter too, more than they usually get credit for. A parent’s move-in timeline is often tied to a health event, a lease ending, or a decision that’s already overdue. A 450 to 660 sq ft model that delivers in 4 to 5 months gets someone settled faster than a larger home that takes 6 to 9 months, and for a single parent, the smaller footprint is rarely a real sacrifice.
The models that fit
| Model | Size | Beds/Baths | All-inclusive price* | Why it fits |
|---|---|---|---|---|
| Four Fifty | 450 sq ft | Studio / 1 bath | $180,000 | Lowest cost entry point; built for aging-in-place and a private studio for one |
| Six Sixty | 660 sq ft | 1 bed / 1 bath | $287,000 | The all-rounder: a real bedroom, single-level rectangle layout, short walk everywhere inside |
| Seven Forty-Nine | 749 sq ft | 2 bed / 1 bath | $347,000 | Two-household living with real privacy, good for a parent who wants a guest room or caregiver space |
| Eight Eighty-Five 2/2 | 885 sq ft | 2 bed / 2 bath | $402,000 | Two full bathrooms means true in-law independence, no sharing a bathroom with anyone |
| Nine Forty-Five 2/2 | 945 sq ft | 2 bed / 2 bath | $412,000 | The most room built specifically for downsizing parents who want a full second suite |
*Includes a permitting budget, not final permit costs. Permits and property-specific site work (septic, retaining walls, etc.) vary by property and are confirmed in your feasibility study.
The top pick: Six Sixty
The Six Sixty is Framework First’s most popular model for a reason, and it’s also the most common fit for a single aging parent. At 660 sq ft, it’s large enough for a real bedroom, a full bathroom, a proper kitchen, and a living area, but small enough that nothing in it requires a long walk. The rectangle footprint keeps the layout simple and predictable, which matters a lot when the person living there is adjusting to a new space.
At $287,000 and a roughly 5-month build, it also hits a sweet spot on cost and speed that the larger models can’t match. That price already includes a permitting budget, plans, the foundation, the factory build, delivery, utility hookups, appliances, and final inspection. Your exact permit costs depend on your city and get confirmed during your feasibility study, so there’s no bill hiding outside that process.
When one parent isn’t the whole story
Plenty of families are not housing one parent, they’re housing two, or planning for a parent plus a caregiver, or want a layout flexible enough to become a rental again down the line. That’s where the runner-up models come in.
The Seven Forty-Nine (749 sq ft, 2 bed/1 bath, $347,000) is the right call when privacy for a couple matters more than a second bathroom, its L-shaped layout naturally separates the bedrooms from the shared living space. The Eight Eighty-Five 2/2 (885 sq ft, 2 bed/2 bath, $402,000) is the better pick when two full bathrooms are non-negotiable, which is often the case for two parents sharing a home. And the Nine Forty-Five 2/2 (945 sq ft, 2 bed/2 bath, $412,000) gives you the most breathing room of the three, officially built for downsizing parents who want a genuine second suite rather than a compact add-on.
If mobility and accessibility details, grab bars, roll-in showers, wider doorways, are part of the decision, bring that up early. Site planning, including exactly where the ADU sits relative to the main house for easy caregiving access, gets worked out during your feasibility study, so it’s worth raising before your model is locked in.
Pricing, financing, and next steps
Every price above already has a permitting budget folded in, not a base price with add-ons waiting, though final permit costs are set by your city and confirmed during your feasibility study. Before you commit to a model, run your numbers through the ADU cost calculator to see how size and layout affect your total, and start a feasibility study to confirm what will actually fit and work on your specific lot. Our pricing page breaks down what’s included across every model in the lineup, and our process page walks through what happens from signed contract to crane day.
Frequently asked questions
What’s the best ADU size for one aging parent moving in?
The Six Sixty is the best fit for most single-parent situations: 660 sq ft, 1 bedroom, 1 bathroom, $287,000 with a permitting budget included, delivered in about 5 months. Its rectangle layout keeps the bedroom, bathroom, and kitchen close together on one level.
Is the Four Fifty studio big enough for a parent to live in long-term?
For a parent who wants the smallest possible footprint and minimal upkeep, yes. The Four Fifty is a 450 sq ft studio with 1 bathroom, priced at $180,000, and it’s built specifically for aging-in-place and a private studio for one. The tradeoff is no separate bedroom, so it fits best for someone who prioritizes simplicity and cost over extra space.
What if two parents are moving in together?
Go with a 2 bed/2 bath model so each parent has full privacy and their own bathroom. The Eight Eighty-Five 2/2 (885 sq ft, $402,000) and Nine Forty-Five 2/2 (945 sq ft, $412,000) both fit this, with the Nine Forty-Five 2/2 offering more overall square footage and officially built with downsizing parents in mind.
Are these ADUs single-story, and can they work for someone with mobility needs?
Yes, every Framework First model is single-level with no stairs. For specific mobility features like grab bars, roll-in showers, or wider doorways, bring those needs up when you start your feasibility study so they can be planned into your build from the start.
How long does it take to get an ADU built for a parent moving in soon?
Timelines run 4 to 9 months depending on the model. The smaller aging-parent-focused models move fastest: the Four Fifty is about 4 months, and the Six Sixty is about 5 months. The larger 2-bath models, like the Eight Eighty-Five 2/2 and Nine Forty-Five 2/2, run about 6 months.
Can the ADU be placed close to the main house for easier caregiving?
Placement on your lot, including distance from the main house, is worked out during site planning as part of your feasibility study, since it depends on your lot’s setbacks and layout. Raise it early so your model choice and your site plan match what your family actually needs.
Ready to find the right fit for your family? Start your feasibility study or browse the full model lineup to compare every option side by side.