How much does home addition cost in Boulder? The usual addition job filed with Boulder is $100,000, from 368 priced permits (October 2023 through September 2026); the middle half of firms file between $70,000 and $313,436. A filed value is what the contractor wrote on the permit, not a quote or the final bill.
The usual addition job filed with Boulder is $100,000, from 368 priced permits, October 2023 through September 2026. The middle half of firms usually file between $70,000 and $313,436. Half of jobs were filed for less, half for more. A filed value is what the contractor wrote on the permit, not a quote or the final bill. An addition permit here usually takes 415 days from issue to final inspection. How long permits take →
Firms split into thirds by the usual value of the homes they work on, with each third's usual filed value weighted by permits. Home values: Boulder County Assessor values.
| Firms working on | Usual home value | Usual filed value | Firms | Permits |
|---|---|---|---|---|
| Lower third | under $1,232,100 | $195,000 | 61 | 125 |
| Middle third | $1,232,100–$1,714,175 | $125,000 | 61 | 113 |
| Upper third | $1,715,350 and up | $142,685 | 62 | 129 |
Top 10 by permits in the last 12 months. Usual is each firm's middle filed value; middle half is the range its middle half of jobs were filed in; both are shown for firms with 5 or more priced permits. Busy is not the same as careful: pick what you value to build a list.
| Firm | Permits | Last 12 mo | Usual | Middle half | Finished |
|---|---|---|---|---|---|
| High Plains Renovation Ltd | 15 | 12 | $7,000 | $6,427–$7,445 | — |
| Decks by Caio | 14 | 6 | $12,439 | $8,661–$16,009 | 8 of 8 |
| O'Keefe Built, Inc | 13 | 6 | $29,452 | $25,155–$41,310 | 6 of 8 |
| Melton Design Build dba Melton Construction Inc | 12 | 4 | $142,685 | $69,677–$262,246 | 7 of 8 |
| Heartwood Builders, Inc | 11 | 4 | $125,000 | $71,000–$202,000 | 6 of 7 |
| Sobo Design & Build | 9 | 4 | $313,020 | $259,000–$360,000 | 6 of 7 |
| Trad Design Build LLC | 8 | 3 | $435,000 | $208,750–$688,750 | 3 of 5 |
| Cosman Construction | 6 | 3 | $50,000 | $35,298–$58,975 | — |
| Rob Luckett Builders | 6 | 3 | $212,750 | $191,294–$243,875 | — |
| Living Stones Construction | 4 | 3 | — | — | — |
Line your quote up against the file. In Boulder, 1 in 10 addition firms' usual jobs sit under $12,400, the middle half between $33,100 and $300,000, and 1 in 10 over $467,000.
Boulder files the fewest addition permits in January (70 against an average month of 100) and the most in May (130). If you can choose, ask for quotes in a quiet month. We have no prices by month, so this is about crews' schedules, not a discount. When each trade is busiest in Boulder →
Source: City of Boulder construction permits. The window is October 2023 through September 2026; a permit filed after that isn't here yet.
Usual is the middle permit: half were filed for less, half for more. Only permits with a filed value count; a value of $0 or none is left out.
The spread is approximate: we keep seven points of each firm's own range of filed values, not every permit, and pool them.
Nobody paid to be on this page and nobody can. How the records work in Boulder →
Addition cost in other cities: Orlando Cincinnati Miami Minneapolis Denver San Diego Honolulu Albuquerque Greensboro Saint Paul Arlington, VA Scottsdale Somerville Cary Naperville Bellevue Cape Coral Bellingham Bend San Francisco Anaheim Columbus, OH Marin County (unincorporated)
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