Renovating a Narrow Townhouse in Brooklyn
Narrow Townhouse - 14ft wide Brooklyn townhouse clad in dark gray brick.
Original tax photo of the property as provided by the NYC Department of Finance circa 1940 (Original structure estimated to be built late in the 1800s)
Townhouses emerged in New York City during the late 19th and early 20th centuries, shaped by both real estate economics and urban planning. These narrow dwellings offered an efficient solution for developers seeking to maximize limited urban lots while providing housing suited to the growing middle class.
One of the defining strategies was the use of shared party walls. Instead of constructing four exterior walls for every house, builders paired homes side by side, allowing them to share structural brick walls with their neighbors. This approach dramatically reduced the amount of material needed, cut construction costs, and made rowhouse development feasible on a large scale. Over time, whole blocks of connected townhouses emerged, creating the continuous street walls that now define historic neighborhoods like Carroll Gardens, Gowanus, Fort Greene, and Bed-Stuy.
These shared walls gave rise to the distinctive proportions of the townhouse: typically 16 to 20 feet wide but extending 40 to 60 feet deep. The efficiency of the party wall system enabled density while still offering private ownership and outdoor space — a balance that continues to make townhouses desirable today.
In Gowanus, COPA was approached to renovate a townhouse only 16 feet wide, leaving an interior clear dimension of just 14 feet. Projects like this highlight both the challenges and the design opportunities that come with the narrow townhouse typology.
Structural Integrity
Older townhouses were built with sturdy brick walls and timber joists, but time reveals weaknesses. Foundations may have settled, floor joists can sag, and masonry often requires reinforcement. Renovations usually start with structural upgrades—sistering joists, underpinning foundations, or adding new steel to support open floor plans.
These interventions may not be visible once complete, but they form the backbone of a successful renovation and often account for the majority of costs. Without addressing structural integrity first, the most polished design risks being undermined by uneven floors, water intrusion, or long-term instability.
Energy Performance & Envelope Upgrades
Townhouses were never designed with insulation in mind. Solid brick walls, drafty windows, and uninsulated floors made heating and cooling costly and uneven. Renovating today means complying with the 2020 NYC Energy Conservation Code, which emphasizes airtight construction, modern insulation, and reduced carbon emissions.
Insulation strategies
Closed-cell spray foam is often the go-to, sealing cavities tightly while providing high R-values in limited wall depths.
Mineral wool or cellulose can offer greener performance, particularly when paired with continuous exterior insulation.
Under the current code, continuous insulation alone can be used if it achieves the required R-value or U-factor for Climate Zone 4A.
Window performance requirements
Fixed windows: maximum U-factor ≈ 0.36
Operable windows: maximum U-factor ≈ 0.43
SHGC: limited depending on shading and orientation
Multi-unit considerations
For owners who rent part of the townhouse, the floor assembly between units must serve as both a thermal and acoustic boundary. In practice, insulating all floors—not just those required by code—creates a quieter, more comfortable home overall.
Once the envelope is upgraded, attention often shifts to how outdoor and additional spaces can expand the way a townhouse functions.
A contemporary outdoor kitchen is installed on a rooftop, featuring stainless steel cabinetry and a black paneled backdrop.
A plywood deck under construction sits atop a townhouse roof, framed by low masonry walls and overlooking the street below.
Rooftop or No Rooftop?
Historically, townhouses didn’t have rooftop decks—access was limited, and roofs were treated as service zones. Today, rooftops are among the most valuable spaces you can create, offering privacy, sunlight, and outdoor living in a dense city.
Adding a roof deck requires careful attention to:
Insulation strong enough to support pavers and foot traffic
Stormwater drainage to manage runoff
FDNY requirements that maintain clear space for emergency ladder access
When executed properly, a rooftop deck can transform a townhouse, expanding usable space without altering the street-facing façade.
A brick staircase with metal railing leads to a backyard terrace enclosed by warm wood fencing.
A rooftop terrace with tiled pavers features a small raised planter, offering open views of the surrounding cityscape.
Backyard Design in a Dense Environment
Brooklyn backyards are modest in size, but they remain treasured pockets of open space. Thoughtful design—layered plantings, privacy screens, or compact patios—can make these outdoor areas feel secluded and lush.
A deck off the kitchen is especially desirable, creating a direct connection between everyday living and the outdoors.
A clean, modern home office features a built-in desk with dual workstations, natural light from a high window, and simple furnishings.
Expanding Upward: Pop-Ups
Many owners want to add square footage through a vertical extension, or “pop-up.” Zoning and Landmarks regulations set strict limits, but even a modest addition can unlock a new bedroom, office, or studio. The key is integrating the addition so it respects the proportions of the original townhouse and its neighbors.
In landmarked districts, the requirement is that the pop-up must not be visible from the street, preserving the historic character of the block. A simple diagram or sightline study is often used to demonstrate compliance to plan examiners.
A contemporary kitchen is designed with a central marble island, streamlined cabinetry, and abundant natural light from a full-height window.
Built-Ins: Designing for Narrow Widths
With typical widths of 16 to 20 feet, townhouses demand smart space planning. Built-in shelving, banquettes, desks, and storage walls are invaluable—they maximize function without crowding circulation, allowing each room to work harder within a compact footprint.
In the Narrow Townhouse, millwork became a tool to both organize storage and define spatial zones:
Entry foyer storage: A custom storage wall creates a small foyer that transitions the experience of entering the home. Shoes, coats, and everyday items are tucked neatly away, giving the main living areas a sense of calm.
Kitchen efficiency: Within a compact kitchen, a hidden coat closet was integrated alongside pantry storage. Everyday essentials like brooms and sweepers were compacted into the same system, keeping the kitchen streamlined.
Living room definition: Custom shelving around the television frames the living area, providing a focal point while doubling as display and storage. In a narrow plan, this establishes a “room” without the need for walls.
Closet and bath integration: Cabinets served as partitions, forming the walls of a walk-in closet while also providing bathroom storage. This reduced circulation space while increasing usable storage volume.
Workspace in the pop-up: On the upper level, a built-in desk anchors the office. Integrating the workstation into the architecture keeps the room flexible—able to function as an office today and adapt to other uses in the future.
Together, these built-ins turned limitations into opportunities. Instead of crowding narrow rooms with freestanding furniture, custom millwork allowed each square foot to serve multiple purposes, making the townhouse feel more spacious, coherent, and tailored to daily life.
To learn more about this project, visit our Narrow Townhouse project page.
If you’re interested in collaborating on a property renovation, reach out through our Contact Us page.
