Owning a Brooklyn townhouse is a dream for many — and it’s easy to see why.

• You get full control of the lot and building, so no board approval headaches for renovations.

• You often enjoy lower property taxes than similarly priced condos, thanks to the 6% cap on annual assessment increases for 1–3 family homes.

• Best of all, you can live in one unit and rent out the other(s) to offset your monthly expenses.

That last perk is often the clincher. But here’s the catch: In most two-family townhomes, the owner’s triplex sits above a garden rental — and that garden unit may not meaningfully reduce the carrying costs on a multimillion-dollar property.

Enter: The Magical Double Duplex

This under-the-radar layout offers smarter flexibility, stronger rental potential, and is ideal for co-purchasing. Here’s why it works so well:

Benefit #1: More Flexible Living for Growing Households

Let’s be honest: Many townhouse buyers are part of a 2- or 3-person household, planning to become a 4- or 5-person household in the next few years. And yet, when they tour an upper triplex, I often hear the same thing:

The double duplex layout solves this. Typically, it includes a 2-bedroom garden-level unit and a 3-bedroom upper duplex—like what we’ve seen at 433 Pacific, 390 Pacific, or 139 Cambridge (one of my all-time favorite sales).

The beauty is in the long game: Owners can start in the smaller unit, then “graduate” to the upper duplex when their needs expand. And down the line, if a full triplex feels right, they can combine the units — usually by relocating the third-floor kitchen to the garden level. It's more feasible than you'd think.

Benefit #2: Rental Income That Actually Moves the Needle

For buyers keeping a close eye on cash flow, a double duplex can be a game changer.

Larger rental units — especially duplexes — are in high demand and short supply. I’m regularly fielding inquiries from renters with $8K–$15K/month budgets, looking for off-market 3+ bedroom rentals across BoCoCa, Brooklyn Heights, Prospect Heights, Fort Greene, Clinton Hill, and North Slope.

This double duplex setup gives you:

• One high-ticket rental to meaningfully offset expenses

• One tenant to manage (far simpler than 2-3 tenants)

• No HPD oversight (which kicks in at 3-family ownership)

In other words: strong income, light touch.

Benefit #3: Co-Purchasing Made Simpler

I’ve long championed the idea of co-buying a townhouse with family or friends—and I’ve helped several groups pull it off. (One of those stories was even featured in The New York Times’ “The Hunt.”)

The double duplex makes this route more viable. It allows both parties to enjoy similarly sized, private spaces — leading to a cleaner, more equal split of expenses.

For those curious: Most of these co-purchase projects plan to condo-convert in a few years, a process far less daunting than most assume. (That’s a blog post for another day, or a private conversation.)

Bottom Line:

If you’re drawn to townhouse living but want more flexibility, better rental income, or a smart co-ownership path, don’t sleep on the double duplex. It’s a small layout shift that opens up a world of possibilities.