Colorado ADU Loan Calculator
Colorado ADU laws loosened sharply under HB24-1152, and Denver in particular has seen a surge in permitted ADU builds. Use this calculator to compare HELOC, construction-perm, and cash-out refi monthly payments against typical Colorado ADU build costs, and see how ADU rent along the Front Range stacks up against the monthly payment.
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Loan amount: $192,000
HELOC
Variable rate, interest-only draw option
Flexible line of credit. Only pay interest on what you draw.
Construction-Perm
Draws during build, converts to mortgage
Funds disbursed by milestone. Permanent loan activates at completion.
Cash-Out Refi
Replaces your current mortgage
Combines existing mortgage + ADU cost into one new 30-year loan.
Rent-coverage estimate
Typical ADU rent in the Mountain region runs about $1,900/mo. That covers roughly 123% of the featured HELOC monthly payment shown above.
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ADU loan product comparison
| Product | Typical rate | Term | Best for |
|---|---|---|---|
| HELOC | 7.5–10.5% variable | 10 draw + 20 repay | Homeowners with 20%+ equity who want flexibility |
| Home Equity Loan | 7.3–10.3% fixed | 10–30 yr | Borrowers who want a fixed monthly payment |
| Cash-Out Refi | 7.5–8.5% fixed | 30 yr | Current mortgage rate already near market |
| Construction-Perm | 8.0–12.0% | 12–18 mo then 30 yr | Ground-up builds over $200K |
| DSCR | 8.5–12.0% | 30 yr | Investors qualifying on rent |
| RenoFi | 8.0–11.0% | 10–20 yr | Limited current equity, new-build ADUs |
Frequently asked questions
What is the best ADU loan in Colorado?
For Colorado homeowners with 20%+ equity, a HELOC or fixed home equity loan is typically the cheapest way to finance an ADU. For new-construction builds over $200,000, Colorado lenders increasingly offer construction-to-permanent loans that fund in draws and convert to a 30-year mortgage at completion. Investors with a rental plan often use a DSCR loan that qualifies against projected ADU rent.
How much does an ADU cost to build in Colorado?
Typical detached ADU builds in Colorado land between $170,000–$340,000. A 750 sq ft two-bedroom unit in Denver usually falls mid-range, while high-end coastal builds push higher once soft costs, site prep, and utility hookups are counted.
Are there state-level ADU grants in Colorado?
Active grant programs rotate frequently. We list the current state-level programs in the calculator above. Note: the CalHFA ADU Grant Program closed to new applications in December 2023 after all funds were allocated, so California homeowners should look to municipal fee waivers and lender-side incentives instead.
How long does ADU loan approval take in Colorado?
HELOC and home equity loans typically close in 3–5 weeks. Construction-perm loans take 6–10 weeks because the lender must review plans, permits, and a draw schedule. Getting pre-approved before you finalize designs shaves weeks off the project timeline.
Rebuild your cost estimate with different inputs.
Project long-term return on your ADU investment.
Complete guide to every ADU loan product.
Managing a Construction Loan? Stay on Top of Every Draw.
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