ADU & Small House Plans · Boulder, CO
Buy Small ADU Floor Plans Boulder Colorado
Looking to buy small adu floor plans boulder colorado? HousePlans USA draws ADU and small house plans from scratch for the Boulder, CO area. Two or more designers sketch concepts for your lot, you pick your favorite, and permit-ready plans arrive in as little as 24 hours.
From $1,050 · free customization · 30 days of free revisions · pay 75% to start
Why buy ADU and small house plans for Boulder, CO from us
Small homes work harder than big ones: every foot has to earn its place. A backyard ADU can house a parent, earn rent or become a home office.
We draw studios, one- and two-bedroom cottages, garage apartments and affordable starter homes to your city's size, height, setback and parking rules.
ADU rules handled
Size, height, setback and parking limits are checked for your lot before concepts begin.
Live large in less
Vaulted ceilings, lofts and built-in storage make small rooms feel open.
Build it again
PDF unlimited build rights for $395 let you reuse the plan on more lots.
What's included in your ADU and small house plans
- Studio, 1-bedroom and 2-bedroom layouts
- Garage apartment with fire separation details
- Utility routing from the main house
- Aging-in-place details on request
- Unlimited-build rights available for investors
Plan prices by size
| Up to 1,000 sq ft | $1,050 |
| 1,001 – 1,500 sq ft | $1,295 |
| 1,501 – 2,000 sq ft | $1,495 |
| 2,001 – 2,500 sq ft | $1,695 |
| 2,501 – 3,000 sq ft | $1,895 |
| 3,001 – 3,500 sq ft | $2,195 |
Colorado engineer stamp from $750. See every option on our pricing page.
Building in Boulder, CO: local rules your plans account for
- Boulder has strict energy (Boulder Energy Conservation Code), height and floodplain rules, and wildfire rules at the foothills edge.
Building requirements
Building a house in Boulder, CO: what the code requires
Codes adopted locally (no mandatory statewide code)
- Building code
- No statewide residential code. Counties and cities adopt IRC editions with amendments (Denver has its own Denver Building Code).
- Energy code
- State law requires jurisdictions that update codes to adopt a recent IECC edition plus electric- and solar-ready provisions.
- Climate zone
- IECC climate zone 4–7. Insulation, windows and HVAC are sized to match.
- Typical frost depth
- 30–36 in (Front Range), 36–48 in+ (mountains). Footings must extend below the local frost line (confirm with your building department).
- Foundations
- Crawlspace or basement, depending on soil and lot slope.
- Who can draw the plans
- Single-family homes can generally be designed by a non-licensed home designer. A licensed engineer's stamp is often required for structural items, engineered foundations or special hazard zones, or when the local building official asks for it.
- Engineer stamp
- If your jurisdiction requires sealed drawings, add our Colorado Engineer Stamp / Permit-Ready package ($750).
Colorado-specific rules & hazards
- Mountain counties commonly require engineered foundations, high snow loads (often 50–100+ psf) and wildfire mitigation.
- Expansive soils along the Front Range often require a soils report and engineered foundation.
- Heavy roof snow loads and steeper, well-braced roof framing
- Wildfire-resistant materials and defensible-space detailing
Summary for planning only. Codes, editions and local amendments change, so always confirm current requirements with the building department that will issue your permit. Our designers check your jurisdiction before drawing.
How ordering works
- 1
Get inspired
Pick the exterior styles and interior looks you love, or paste links to plans you've seen online.
- 2
Design & instruct
Choose rooms, size, basement, garage and your state, and tell our designers exactly what you want.
- 3
Compare 2+ concepts
Two or more designers each sketch a concept. Pick your favorite designer to draw the full plans.
- 4
Download & revise
Plans arrive by email and in your dashboard by your deadline. Revisions are free for 30 days.
Full guide: ADU and small house plans in Colorado
Buy Small ADU Floor Plans Boulder Colorado: FAQ
Can I build an ADU in Boulder, CO?+
In many cities, yes, but size, setback and parking rules vary. We check your lot's rules before we sketch.
Do you draw garage apartments?+
Yes. We draw one- and two-bedroom apartments over garages, including the required fire separation.
How much do ADU and small house plans cost in Boulder, CO?+
Custom plans start at $1,050 for homes up to 1,000 sq ft and are priced by size. Most family homes come to $2,000–$3,000 all-in, with free customization and 30 days of revisions.
How fast can I get ADU and small house plans for Boulder, CO?+
Standard delivery is 10 business days. Priority, Express, Rush (48 hours) and Super Rush (24 hours, up to 3,000 sq ft) are available at checkout.
Related searches
- Boulder Colorado Contemporary Eco Home Blueprints
- Buy Contemporary Eco House Plans Boulder
- Purchase Modern Mountain Blueprints Boulder CO
- Ready to Build Luxury Plans Boulder Colorado
- Engineering Stamped Blueprints for Sale Boulder CO
- 3 Bedroom Flat Roof Plans Boulder CO
- Buy Small ADU Cottage Plans Denver
- Buy Small Guest House Plans Colorado Springs CO
- Buy Affordable Family Home Plans Woodland Park CO
Let's design your home for Boulder, CO
It takes about 10 minutes, and we save your answers as you go.