When you buy a new home in a Brentwood open-space subdivision, the "acre" that comes with Brentwood's reputation can be about a third of an acre of private lot plus a share of common ground. The city spells this out itself. Its planning guide defines "one acre density" as one acre of land allocated with each home. In some zoning districts that means a lot of at least an acre. In Open Space Residential Development districts, homes "may be on lots that are less than one acre in size," with preserved open space making up the difference.
That definition matters most when you compare two Brentwood homes at similar prices. One sits on an older one-acre lot. The other is newer, sits on a much smaller lot, and backs onto a green belt you share with your neighbors. Both meet the same city standard. The same rule that allows the smaller lot also caps how many homes Brentwood can add, and that cap shows up in the prices.
The newest example sits off Hillsboro Road
On August 3, 2026, the Brentwood Planning Commission took up Ordinance 2026-08, the request to zone about 77 acres west of Hillsboro Road and south of Old Hickory Boulevard. The project is called the Cruise Subdivision. The plan assigns OSRD zoning to 52.82 acres and R-2 Suburban Residential zoning to 23.90 acres. The OSRD layout shows 25 lots with about 32 acres of common open space. The R-2 portion to the west, roughly 24 acres, is planned as a single reserve parcel until that tract can get legal road frontage.
The commission voted 10 to 0 to recommend approval. Before the vote, one commissioner pointed out that if the city didn't annex the land, it would be developed under county rules alone, "which Brentwood is a little bit stricter than." On August 24, 2026, the Board of Commissioners passed the zoning ordinance on second and final reading. It then passed Resolution 2026-76, a voluntary annexation the city manager noted lies within Brentwood's urban growth boundary. Both votes were unanimous.
Here is the arithmetic on the OSRD portion. Take the 32 acres of open space out of 52.82 acres, and about 21 acres remain for 25 lots and their streets. That's well under an acre of private ground per home. Spread over the whole OSRD tract, though, each home accounts for more than two acres. Both numbers describe the same subdivision, and the second one is the one the city's standard measures.
Two districts, two very different lots
Brentwood's code allows both shapes. R-2 is the classic Brentwood pattern, and OSRD is the clustered version.
| Standard | R-2 Suburban Residential | OSRD |
|---|---|---|
| Minimum lot size | One acre | 14,000 sq ft for conventional lots; 21,780 sq ft for transitional lots |
| Density | Set by the one-acre lot minimum | One home per acre of buildable area, not counting standard 50-foot internal street right-of-way |
| Minimum project size | None stated in the material reviewed | 25 acres |
| Lot coverage | Buildings may cover no more than 25% of a lot | Buildings may cover no more than 25% of a lot |
| Next to existing homes | Not applicable | One acre, or at least the size of a smaller adjacent lot, unless open space between them brings the combined area up to that size |
R-2 lots also have to keep 40% green space. A 14,000-square-foot OSRD lot is about a third of an acre, and a 21,780-square-foot transitional lot is exactly half an acre. You can read the full text in Brentwood's OSRD code on Municode.
OSRD also stops a developer from using clustering to squeeze in more homes. The lot count can't exceed what the land would yield under its existing zoning, as shown on the conceptual plan. Clustering changes where the homes go. It doesn't change how many there are.
The city's own example puts it simply. An OSRD subdivision could have 100 homes on half-acre lots, using 50 acres, as long as another 50 acres stays preserved as open space. The 50% share is only an illustration. The code works through a site-specific formula and sets no single required percentage.
Why the city holds the line at one home per acre
Brentwood says the R-2 low-density pattern is meant to limit traffic on its streets and keep development within sanitary sewer capacity. The OSRD code lists other goals for clustering. These include preserving natural and manmade features, reducing disturbance to steep hillsides, keeping open space visible along arterial roads, and providing recreation.
The Brentwood 2030 Plan commits the city to continuing its current residential types and densities in future residential areas, with retirement districts as the exception. When it was adopted in October 2016, the plan already described Brentwood as nearing buildout. It projected that future projects would lean more on infill and redevelopment, which cost more.
Put those pieces together and you can see how supply works here. When a large tract like Cruise joins the city, its home count is set by the one-per-acre math before anyone draws a lot line. The open space comes from giving each house less private land. It doesn't come from adding houses.
What the cap looks like in the July 2026 numbers
The Williamson County Association of Realtors' July 2026 single-family update shows where that scarcity ends up. The August 2026 report has been posted, but its city-level rows were not available to us, so July is the latest city breakdown cited here.
| July 2026, single-family | Brentwood | Franklin | Nolensville |
|---|---|---|---|
| Closings | 79 | 192 | 29 |
| Median sale price | $1,625,000 | $1,125,000 | $935,000 |
| Average sale price | $2,001,367 | $1,507,110 | $1,206,902 |
| Average list price, active | $2,576,086 | $2,018,820 | $1,316,715 |
| Average days on market, closed | 26 | 32 | 32 |
| Months of supply | 4.07 | 3.71 | 4.63 |
In July 2026, Brentwood's median sale price ran $500,000 above Franklin's and $690,000 above Nolensville's. One more Brentwood figure is worth a look. The average asking price on active listings was $2,576,086, while the average closed price was $2,001,367. Those are averages across different groups of homes, so they don't measure discounts. They do show that much of what's listed in Brentwood sits above the price level where most sales were closing that month. Brentwood listings that went under contract in July 2026 took 54 days on average to get there, and homes that closed that month spent an average of 26 days on market.
For anyone shopping new construction, this table has a practical side. The premium you pay to be in Brentwood buys you a place in a city that limits how many homes it will ever add. In an OSRD subdivision, that premium may come with a smaller private lot than an older resale home nearby, along with a view across permanently preserved ground.
Who owns the green space behind the house
The city's planning guide lists maintaining commonly owned improvements as one possible HOA role. In a July 2026 Planning Commission discussion of the Arden Woods replat, city staff said the subdivision's common detention and open-space area would be maintained by the HOA. That replat covered a 1.57-acre parcel and split Lot 12 into two lots, which brought Arden Woods back from 29 lots to its original 30.
OSRD plans also get revised after approval. Rosebrooke South on Split Log Road had its revised OSRD plan approved by the Planning Commission on February 3, 2025, and by the Board of Commissioners on February 24, 2025. The revision kept the lot count the same and proposed a 1.65-acre open-space amenity tract.
If you're touring a home in a Brentwood OSRD subdivision, ask for these before you write an offer:
- The recorded plat for the specific lot, so you know its true square footage and not just how big the view makes it feel.
- The HOA documents covering the common open space, including who maintains it and how that work is budgeted.
- Any revised preliminary plans or replats on file, since layouts like Arden Woods and Rosebrooke South changed after their first approval.
- Whether the lot backs up to an existing neighborhood, because those edge lots fall under the one-acre or matching-size rule and may be larger than interior lots.
Questions buyers ask about Brentwood OSRD lots
Is the Cruise Subdivision for sale yet? The approvals we reviewed cover zoning and annexation. They don't include lot prices, individual lot sizes, or a construction schedule, and we haven't seen that information published yet.
Does an OSRD home still meet Brentwood's one-acre standard? Yes. The standard is one home per acre of buildable land across the subdivision, and the preserved open space is what balances out the smaller lots.
Can a developer use OSRD to build more homes than R-2 would allow? No. The code limits the lot count to what the existing zoning would yield.
If you're weighing a newer Brentwood home on a clustered lot against an older one on a full acre, Kayla Jarmon can pull the plats, HOA documents, and recent comparable sales for both, so you'll know exactly how much land each price includes. If you already own on a Brentwood acre, request your free home valuation and we'll show you how your lot compares with what's being approved now.
