Cosman Construction
Home addition contractor working in Boulder.
- Boulder publishes no contractor license list we can check
5 addition jobs on Boulder permits, 2024 to 2026. 16th most addition permits of 48 contractors in Boulder.
What the public records show
From the city's permits, one question at a time.
| Question | Records show | Mark |
|---|---|---|
| Licensed? | Boulder publishes no contractor license list we can checkThat says nothing about this business either way. | Ask them |
| Jobs on record | 5 addition jobs on Boulder permits, 2024 to 2026Every permit we have for them is addition.Their permits mention 5 decks.16th most addition permits of 48 contractors in Boulder. That counts jobs, not quality.Our Boulder permit records cover September 2021 to September 2026. |
Records: City of Boulder permits.
Cost and timing
All addition jobs in Boulder: $22,000 to $260,000
Half of 503 city permits list an amount in this range. Permit amounts are often lower than what you pay.
- Second-story additions in Boulder: $57,000 to $420,000 (36 permits)
- Garage additions in Boulder: $80,000 to $484,000 (115 permits)
How to read this range
Contractors write a job value on the permit form, and the city uses it to set the permit fee. It is not the contract price, and it is often lower than what you pay. A quarter of the permits list less than this range, and a quarter list more. Use it to see if a quote is in the normal range.
Permit value (not a price)
Their typical permit lists $45,000 (half list more, half less)
That is the figure written on the permit form, which can be far from what you pay. What addition jobs cost in Boulder.
Get 2 or 3 written quotes.
Track record
Where they work most
- 803052 jobs
- 803011 job
- 803031 job
- 803041 job
Latest jobs
Permit values are what the contractor wrote on the permit form, not what the owner paid.
| Date | Work | ZIP | On the permit form |
|---|---|---|---|
| Apr 27, 2026 | AdditionReplacement of existing back deck with similar footprint | 80301 | $55,000 |
| Mar 25, 2026 | AdditionReconstruction of back deck and stairwell/roof ADDITION | 80305 | $45,000 |
| Oct 14, 2024 | AdditionFull rebuild of 140 square foot back deck and stairs ADDITION | 80303 | $20,000 |
| May 8, 2024 | AdditionReconstruction of North and West deck to same footprint ADDITION | 80304 | $60,300 |
| Apr 29, 2024 | AdditionReplacement of existing back deck and stairs to same footprint ADDITION | 80305 | $32,065 |
What to ask before you hire
About Cosman Construction
- Ask for their license number and check it with the state.
- Ask what the warranty covers and for how long, in writing.
- Search their name on the Better Business Bureau site, and read their reviews.
Worth asking any home addition contractor
- Can you show me proof of liability insurance and your bond?
- Do you handle the plans and engineering, or do I hire them?
- Who will run the job day to day, and who are the subcontractors?
- Who pulls the permits, and what is the payment schedule?
Get a quote from Cosman Construction
Five quick questions. We pass your request to Cosman Construction.
Request for Cosman Construction
- Where
- Job
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- 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.
We pass it to Cosman Construction. 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 roomMore home addition contractors near 80305 and 80301
- Decks By Caio
- O'keefe Built, Inc
- High Plains Renovation Ltd
- Heartwood Builders, Inc
- Smiley Inc
- Pr Builders Dba Ace Septic and Excavation
See all 48 home addition contractors in Boulder, ranked by jobs
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