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See where Boston buildings were last permitted, on one map
For Boston architects, developers and real estate attorneys, one of the first things worth knowing about a block is which buildings have seen recent work and which have sat untouched for years. Stratum’s permit heat map colors every building on the Map by the years since its last significant permit, so that pattern shows up at a glance.
The 44-second walkthrough below turns the layer on, reads the legend and its source note, collapses and reopens the key, and shows how the colors behave alongside nearby precedents.
Turn on the layer and read the colors
In Layers, turn on Permit heat map. The Building permit activity legend groups buildings by years since the last significant permit:
- Under 2 years
- 2–5 years
- 5–10 years
- 10–20 years
- None since 2006
- Not matched to a parcel
The source note at the bottom of the legend says where the data comes from: City of Boston approved permits, 2006 to Jul 21, 2026.
Hide the key without losing the layer
Click Hide to collapse the legend when you want more of the map, and Show to bring the key back. The layer stays on the whole time.
Read it next to precedents
Open a parcel’s Precedents tab and the heat colors dim while decision markers are shown, with a note in the legend, so nearby ZBA and BPDA records stay readable. Return to Details and the normal colors come back.
Permit activity is context, not a condition survey. A recent permit does not tell you a building’s condition, and an old one does not mean a site is available. Verify conditions on site and check records with the City before relying on them.
The permit heat map is part of the signed-in beta; see current access. To start with a single parcel, the Map lets you look up zoning for up to three Boston properties with no sign-up.