# Building permits at 225 31st St, Boulder, CO

Two permits here in the last two years. The newest, Aug 28: Conversion of an existing 1-story. Boulder publishes permits without map coordinates, so this address has no map and no quarter-mile list.

## At this address

| Date | Type | Work | Cost | Permit |
|---|---|---|---|---|
| Aug 28, 2026 | Fence, wall or deck | Conversion of an existing 1-story, detached studio into an accessory dwelling unit (adu). Interior alterations/remodel to 134 sf of the existing 676 sf detached studio, w/ associated mechanical, electrical & plumbing including: 1) the conversion/re-configuration of an existing office into a new kitc | $170,000 | [BLD-ACC2026-00034](https://nearbypermits.com/boulder/permit/BLD-ACC2026-00034/) |
| Aug 24, 2026 | Fire systems | nfpa13D sprinkler system | $13,580 | [FIR2026-00287](https://nearbypermits.com/boulder/permit/FIR2026-00287/) |

## More on this street

Other addresses on 31st St with permits, nearest house number first:

- [235 31st St](https://nearbypermits.com/boulder/address/235-31st-st/): newest permit Mar 9, 2026
- [260 31st St](https://nearbypermits.com/boulder/address/260-31st-st/): newest permit Jul 21, 2025
- [270 31st St](https://nearbypermits.com/boulder/address/270-31st-st/): newest permit Jun 11, 2026
- [137 31st St](https://nearbypermits.com/boulder/address/137-31st-st/): newest permit Jul 29, 2025
- [320 31st St](https://nearbypermits.com/boulder/address/320-31st-st/): newest permit Nov 6, 2024
- [330 31st St](https://nearbypermits.com/boulder/address/330-31st-st/): newest permit Oct 8, 2025
- [701 31st St](https://nearbypermits.com/boulder/address/701-31st-st/): newest permit Jul 21, 2026
- [765 31st St](https://nearbypermits.com/boulder/address/765-31st-st/): newest permit Oct 24, 2024
- [780 31st St](https://nearbypermits.com/boulder/address/780-31st-st/): newest permit Dec 1, 2025
- [2255 31st St](https://nearbypermits.com/boulder/address/2255-31st-st/): newest permit Jul 31, 2026

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Source: Boulder Planning and Development Services permit data (https://www.arcgis.com/home/item.html?id=e3ff6248e4a547bcba31025d2c5c9fee). Checked 2026-10-07 19:08 UTC. Nearby Permits, https://nearbypermits.com. JSON API and MCP server: https://nearbypermits.com/developers/

Both permits at this address: https://nearbypermits.com/boulder/address/225-31st-st/