ADU California Inc.Steel-Framed Backyard Homes
ADU ModelsProcessServicesPortfolioFinancing
More
Backyard BuildingsStorage, workshop and garden concepts.Why SteelHow the framing and wall system work.Cost CalculatorBuild a preliminary project range.Regions & City GuidesExplore Northern California, Central Valley and Southern California.Knowledge CenterCosts, permits, models, systems and planning guides.ContactReach the ADU California Inc. team.
(650) 400-7606Check my property

California ADU financing planner

Understand the payment before choosing a financing path

Compare a real amortized payment, total interest, rate sensitivity, equity and debt ratios. Every market benchmark is dated and sourced; every property or income figure remains yours to verify.

Calculate a scenario Build a project estimate

Planning scope

  • Fixed-rate principal and interest
  • Optional combined LTV and DTI snapshot
  • User-entered rent and gross ROI scenario
  • No approval, lender quote or rent forecast

Transparent planning calculator

Test a complete financing scenario

Start with an editable project example, then replace every assumption with your own lender and household information. Results update immediately and never represent credit approval.

Loan assumptions

The $300,000 starting value is an editable example, not an average ADU price.

$
20%

$60,000 cash; $240,000 financed.

Starting rate for this fixed-payment scenario

The California fixed-equity average is selected first. Mortgage averages are included only for payment comparison.

MonitorBankRates California home equity rate tracker · data as of 2026-09-03. A monitored California market average for fixed home equity loans. It is an editable planning benchmark, not an ADU loan offer or a rate available to every borrower.

7.26%

Enter the actual APR from a Loan Estimate when available.

Repayment term
Equity and debt snapshot

Optional inputs calculate combined LTV and post-project DTI. They do not determine eligibility.

$

Use a current appraisal or your own planning estimate.

$
$
$

Include recurring debt payments you want in this planning ratio.

Optional rent and ROI assumptions

ADU California Inc. does not supply a rent forecast or property-value claim here. Enter independently researched values only.

$
$

Estimated payment

Your planning result

$2,192 / month

Principal and interest only. Taxes, insurance, fees, existing mortgage payments, utilities and operating costs are excluded.

Loan amount
$240,000
Cash contribution
$60,000
Total interest
$154,503
Total loan payments
$394,503

Rate sensitivity

6.26% APR$2,059/mo
7.26% APR$2,192/mo
8.26% APR$2,329/mo

Lenders use their own underwriting rules, valuations, credit criteria, income calculations and product limits. These ratios are informational and do not say whether you qualify.

ADU California Inc. is not presenting itself here as a lender or loan broker.

Choose the product after the project

Four common paths to compare

The lowest advertised rate may not produce the lowest total cost. Compare how funds are released, whether the rate can change, which property secures the loan, and what happens to your existing mortgage.

Home equity loan

A lump-sum second mortgage that may use a fixed or adjustable rate. Compare its payment with your existing mortgage and verify all fees.

Ask: Do I have enough verified equity, and is the payment predictable?

HELOC

A revolving line secured by home equity. HELOC rates are usually variable, so both the payment and available credit can change.

Ask: What index, lender margin, draw period and repayment rules apply?

Construction or renovation loan

A project-specific product that may release funds through construction draws and require plans, budgets, inspections and a completion schedule.

Ask: Which project documents must be complete before underwriting?

Cash-out refinance

A new mortgage can replace the existing one and release equity. Compare the cost of repricing the entire mortgage, not only the ADU funds.

Ask: Does replacing my current mortgage improve or worsen the full cost?

Verified starting points

California programs and consumer guidance

There is no single statewide ADU loan or California-wide ADU interest rate. Program availability can be local, income-limited, property-specific or temporarily closed, so verify the current terms with the named agency.

California HCD funding directory

State-maintained starting point for ADU assistance and selected local programs. Availability and eligibility vary by program and jurisdiction.

Open official source

CalHFA ADU Grant status

CalHFA says the latest ADU Grant funding round was fully allocated on December 28, 2023. Treat anyone offering access to that closed round with caution.

Open official source

CFPB home-equity guidance

Federal consumer guidance explains the difference between a home equity loan and a HELOC, including variable-rate and repayment risk.

Open official source

Next useful step

Refine the project scope before lender underwriting

A lender needs dependable numbers. Start with the property, model, finish level and site constraints so your financing conversation is based on a preliminary project range rather than a guess.

Check my property

San Jose financing context

Financing an ADU in San Jose?

Use the San Jose financing guide to connect a realistic project budget with permit timing, early preconstruction costs, contingency, draw schedules, and lender-specific requirements.

San Jose ADU financing guide

Let’s build your ADU

Your property.
Your next chapter.

Explore the possibilities for your California property.

Check my property
Architectural concept of a modern California ADU in a landscaped garden, shown in natural daylight
Design concept

Let’s talk about your project.

(650) 400-7606sales@adu.zone

San Jose office

84 West Santa Clara Street Suite 700
San Jose, CA 95113
(650) 400-7606Get directions

Walnut Creek office

1990 N California Blvd, 8th Floor
Walnut Creek, CA 94596
(925) 744-5040Get directions
ADU California Inc.
  • Houzz
  • Facebook
Legal & disclosuresPrivacyTerms of useAccessibility
CSLB License #1163442

© 2026 ADU California Inc. All rights reserved.

San Jose · Walnut Creek · California