The project involves renovating the existing basement and adding an 80-square-foot rear entry
Addition at 665 Maxwell Ave, Boulder
Boulder Planning and Development Services permit BLD-SFD2025-00089: issued Oct 27, 2025 for addition work at 665 Maxwell Ave. The project involves renovating the existing basement and adding an 80-square-foot rear entry. The basement floor will be excavated approximately three feet to achieve a 10-foot ceiling height, requiring foundation reinforcement. The electrical panel will be relocated, and the existing HVAC system will be replaced with an electric heat pump and a gas air handling unit, to be design-build. COB additional description - scope includes excavation of existing crawl space (approximately 271 sf) under north end of dwelling, approximately 7 feet to match proposed excavation depth in the existing basement (approximately 670 sf). Proposed basement plan to include 1 bedroom/office, 1 bathroom, storage/mechanical area, living room / family room, and wet bar. Expansion of existing basement window openings and new window wells for egress.
- Permit number
- BLD-SFD2025-00089
- Issued
- Type of work
- Addition
- Status
- Issued
- Reported cost
- $225,500
- ZIP code
- 80304
- City's category
- Building Permit - Single Family Detached Dwelling, Addition and Alteration
- City's status
- Issued
- Source
- Boulder Planning and Development Services permit data (this record)
Type of work and status are our own standard labels, so permits compare across cities. The city's wording is in the "City's category" and "City's status" rows. We show costs under $100 as not listed, because filers often enter $0 or $1 when the city doesn't require a cost.
All permits at 665 Maxwell Ave, and what's permitted nearby
Boulder Planning and Development Services updated its data Oct 6, 2026. We checked it Oct 7, 09:02 UTC. See the city's official records.
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