This week in the data
This inaugural Zonyard intelligence brief establishes a baseline for Cambridge's redevelopment potential. With no deltas from previous weeks, we are setting the stage for future analysis. The city currently holds 12,938 parcels, encompassing a total building area of 106,259,225 square feet. A significant 60,936,076.3 square feet of Gross Floor Area (GFA) remains unused across 789 underbuilt parcels, representing substantial development potential. The total assessed value of these properties stands at $73,831,733,885.
ADU potential and lot splits
Cambridge presents compelling opportunities for Accessory Dwelling Unit (ADU) development and lot splits, particularly on single-family and two-family parcels with surplus lot area. While specific residential parcel counts for these types aren't delineated in this dataset, the median lot sizes and existing GFA metrics across various zip codes offer strong indicators. Developers, architects, and investors should focus on areas exhibiting larger median lot square footage and lower existing FAR (Floor Area Ratio) figures, as these are typically where dimensional plausibility for ADUs or subdivision is highest under current Cambridge zoning rules.
Consider zip codes with median lot sizes exceeding the typical footprint of an existing primary residence. For instance, `02138` (Harvard Square / West Cambridge) boasts a median lot size of 5,662.8 sq ft, and `02140` (North Cambridge / Porter) has a median of 4,356 sq ft. These areas, particularly `02138`, also have a relatively high median total value ($2,960,500) and median land value per sq ft ($249.19), suggesting a robust market where ADU additions could significantly enhance property value or lot splits could unlock substantial equity. Although `02142` (Kendall Square) has a very high median lot size (53,143.2 sq ft) and land value, its median existing FAR is lower, and the parcel count is much smaller, indicating a different development profile, likely larger-scale commercial or institutional, rather than single/two-family ADU opportunities.
The overall unused GFA of over 60 million square feet across 789 underbuilt parcels signals a city ripe for infill development. Targeting residential parcels within these `underbuiltParcels` lists, especially those in `B` (Residence B) and `A-2` (Residence A-2) zones common in `02140` and `02138`, will likely yield the most promising ADU and lot split candidates.
Zip-code investment read
When evaluating investment for ADUs or lot splits, capital should prioritize zones with a combination of high median lot size, reasonable land value per square foot, and robust residential parcel counts. Here's a comparative look:
- `02138` (Harvard Square / West Cambridge): This zip code offers the highest median total value ($2,960,500) and a substantial median lot size (5,662.8 sq ft). With 2,481 residential parcels and 119 underbuilt parcels, it presents a prime target for high-value ADU additions or lot splits, despite a higher median land value per sq ft ($249.19). The `A-2` and `A-1` zones are prevalent here.
- `02140` (North Cambridge / Porter): A strong contender with 3,626 residential parcels and the second-highest median lot size (4,356 sq ft). Its median total value ($1,638,200) and land value per sq ft ($149.71) are more accessible than `02138`, offering a broader range of ADU or lot split projects. It has the highest number of underbuilt parcels (182) among the residential-heavy zips, and `B` zones dominate.
- `02139` (Central Square / Mid-Cambridge): While having the highest number of residential parcels (4,221), its median lot size (3,920.4 sq ft) is slightly smaller than `02140` or `02138`. The median land value per sq ft ($269.31) is also higher. Opportunities here might be more focused on ADUs rather than lot splits, due to the slightly denser character and smaller median lot sizes. It also has a significant 276 underbuilt parcels.
- `02141` (East Cambridge / Wellington-Harrington): With the smallest median lot size (2,613.6 sq ft) among the primary residential areas and a high land value per sq ft ($274.17), this area might be less suitable for lot splits but could still offer ADU potential on larger-than-median individual parcels. The median existing FAR is also the highest, indicating a more built-out environment.
Risk assessment involves considering the median land value per square foot, with `02140` offering the lowest entry point for land, and `02138` representing a higher-value, lower-volume play. `02139` sits in the middle, balancing volume and value.
What to do next
1. Target Zips with Large Median Lots: Focus initial screening on `02138` (Harvard Square / West Cambridge) and `02140` (North Cambridge / Porter) due to their higher median lot square footage, making ADUs and lot splits more dimensionally viable.
2. Filter for Underbuilt Residential Parcels: From the identified zips, cross-reference with the list of `underbuiltParcels` within `02138` (119 parcels) and `02140` (182 parcels). These parcels are likely to have the necessary GFA capacity for new development.
3. Prioritize Lower FAR & Specific Zones: Within the targeted parcels, look for those with existing FAR significantly below the median for their zone (e.g., in `B` or `A-2` residential zones) to identify properties with substantial remaining development capacity for an ADU or a new lot.