Market Insights  /  Rittenhouse
Development Watch · Rittenhouse

139 N 23rd StDelivered

115-unit residential new construction, zoned RM1.

A 115-unit residential building is set to rise at 139 N 23rd St in Rittenhouse, one of the larger new-construction projects underway in Philadelphia this cycle. It was cleared to build in Aug 20, 2021.

The 35,474 sq ft site is zoned RM1, which supports a building on the order of 4 stories by right. The parcel last changed hands in 2020. The plans call for new construction of a four (4) story building with roof deck and pilot houses for use as one hundred fifteen (115) dwelling units with below grade accessory parking garage as per approved plans. building located within the zone ae sfha and to include manual floodproofing with emergency operations plan. elevation certificate required to be submitted to field inspector upon completion of first floor. building to be fully sprinklered per nfpa 13 and contain standpipes per nfpa 14. *2018 ibc review* **separate permits required for mep & fire suppression work** amendment approved 9/5/21 amend new construction permit cp-2020-004309 to revise structural framing system as per approved plans. amendment approved 10/13/21 amend new construction permit cp-2020-004309 to revise structural and foundation systems as per approved plans. .

The owner of record is 139 N 23rd Street Associates LP. The project's plan drawings are on file — worth a look for anyone underwriting the surrounding block.

It isn't rising in isolation. Within a half-mile, 2 other major projects have broken ground since 2022 — roughly 205 units of new supply — including the 121-unit project at 2012-14 Chestnut St, the 84-unit project at 1813 Ranstead St. That kind of concentration is exactly what pulls land values, and buyer attention, toward a block.

We'll update this page as the project progresses — leasing, retail tenants, renderings, and construction milestones as they surface. The relevant question for investors and agents: what are the surrounding parcels worth to a builder now that this is coming?

📄 View the project's plan drawings (PDF)
Schematic massing — illustrative of the ~4-story by-right envelope, not the developer's design.
Units
115
Zoning
RM1
By-right envelope
~4 stories
Lot
35,474 sq ft
Last sale
2020
Cleared to build
Aug 20, 2021
For developers & investors

Underpriced parcels near this project

As this density arrives, InvestPHL is tracking 40 under-built parcels within a half-mile that a developer could still acquire and build — each carrying a builder's max bid. Addresses and figures are members-only.

~186buildable units
████████ Street
CMX2.5 · 0.48 mi away
Max bid to a builder $8.7M · Opportunity Score 98
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~372buildable units
████████ Street
CMX5 · 0.44 mi away
Max bid to a builder $6.3M · Opportunity Score 98
Unlock →
~372buildable units
████████ Street
CMX5 · 0.20 mi away
Max bid to a builder $6.3M · Opportunity Score 98
Unlock →
~308buildable units
████████ Street
CMX5 · 0.18 mi away
Max bid to a builder $5.2M · Opportunity Score 97
Unlock →
~298buildable units
████████ Street
CMX5 · 0.38 mi away
Max bid to a builder $5.1M · Opportunity Score 97
Unlock →
Unlock the 40 nearby opportunities →
The block

What else is rising nearby

Major (8+ unit) new-construction projects filed within a half-mile since 2022 — the density gathering around this site.

121u2012-14 Chestnut St0.41 mi
84u1813 Ranstead St0.47 mi
Progress

How this project is moving

Cleared for occupancy ~100% complete
Estimated from the construction permit sequence — an approximation of stage, not a precise schedule.
Every logged milestone appears here — highlighted ones are the headline stages; the rest track interim construction activity. Checked daily.
Compiled by InvestPHL. Unit counts, scope, and ownership are as recorded and subject to revision; the massing figure is a schematic illustration of the by-right envelope, not the developer's design or a marketing rendering. Verify zoning, status, and title with counsel before acting. InvestPHL does not list, market, or represent any property, buyer, or seller.