Home addition cost in Boulder (2026)
The typical home addition in Boulder was valued at $86,000 on its city permit (middle half: $22,000 to $260,000), across 503 home additions with city permits issued from September 2021 to September 2026.
How the values spread
The numbers behind the chart
| Value on the permit | Jobs | Share |
|---|---|---|
| Under $100,000 | 256 | 51% |
| $100,000 to $200,000 | 88 | 17% |
| $200,000 to $300,000 | 45 | 9% |
| $300,000 to $400,000 | 29 | 6% |
| $400,000 to $500,000 | 23 | 5% |
| $500,000 to $600,000 | 21 | 4% |
| $600,000 and over | 41 | 8% |
Home addition contractors with the most jobs in Boulder
| Rank | Contractor | Jobs | Contact |
|---|---|---|---|
| 1 | Melton Design Build dba Melton Construction Inc | Visit website | |
| 2 | Sobo Design & Build | Visit website | |
| 3 | Decks By Caio | Visit website |
See all 48 ranked home addition contractors
Get quotes from up to 3 home addition contractors
Five quick questions. We send your request to up to 3 contractors who work near you, and email you who they are.
Request for quotes
- Where
- Job
- Start
- Budget
- Goes to
You decide who to hire. Your details go only to the contractors you pick. How we use your details
Sent. We have your request.
Over the next few days we email you up to 3 contractors who fit, and pass your request to them. Replies usually come within a few days.
Your job room keeps the request, your photos and every reply in one place, with an assistant that checks prices against city permits. Keep its link: it is the key to your job.
Open your job roomBy ZIP code
The 5 ZIP codes with the most home additions valued on the permit (at least 20 each).
| ZIP code | Jobs | Median | Middle half |
|---|---|---|---|
| 80304 | 171 | $86,000 | $29,000 to $225,000 |
| 80305 | 146 | $118,000 | $31,000 to $322,000 |
| 80302 | 82 | $143,000 | $50,000 to $399,000 |
| 80303 | 70 | $57,000 | $15,000 to $162,000 |
| 80301 | 34 | $14,000 | $7,000 to $41,000 |
By year
| Year | Jobs | Median | Middle half |
|---|---|---|---|
| 2021 (September to December) | 27 | $45,000 | $18,000 to $90,000 |
| 2022 | 111 | $110,000 | $20,000 to $310,000 |
| 2023 | 86 | $100,000 | $31,000 to $300,000 |
| 2024 | 99 | $80,000 | $30,000 to $235,000 |
| 2025 | 98 | $126,000 | $26,000 to $291,000 |
| 2026 (January to September) | 82 | $66,000 | $17,000 to $197,000 |
What the records show
- Share of jobs in each budget range: under $100,000: 51% (256 of 503); $100,000 to $250,000: 22% (111 of 503); $250,000 to $500,000: 15% (74 of 503); over $500,000: 12% (62 of 503).
- The median was $110,000 in 2022 (111 jobs) and $126,000 in 2025 (98 jobs), up 15%.
- Across the ZIP codes above, the median ran from $14,000 in 80301 to $143,000 in 80302.
Every figure here is the job value written on the city permit, not the price paid. Permit values can be higher or lower than the final price, so get more than one quote. Values under $1,000 are placeholders and are left out. Median and middle half: half of the jobs were valued above the median; the middle half runs from the 25th to the 75th percentile. Source: Boulder construction permits, from September 2021 to September 2026. Data updated October 8, 2026. The same figures as data: addition.json.