How Much Can You Borrow on a Bank Statement HELOC for an Accessory Dwelling Unit?

The Quick Read: It depends on current home value, the combined loan-to-value ceiling for your occupancy and credit tier, what you still owe on the first mortgage, and the program’s line cap, because the line is sized from today’s equity and never from what the finished accessory dwelling unit will be worth. Bank statements change how income is documented. They do not change the equity math.

• The formula is current value times the combined ceiling, minus what is already owed on the property.
• On the network’s programs, the ceiling is 70% on an investment property. It reaches 90% on a primary residence or second home, but only at a 720 credit profile.
• The maximum line is $750,000 on a primary residence and $500,000 on a second home or investment property.
• The unbuilt unit’s future value and projected rent do not raise the line.
• Every figure is subject to lender guidelines and full file review.

Key Terms Defined

HELOC: A home equity line of credit is a revolving line secured by the property, with a draw period followed by a repayment period.

Bank statement HELOC: This is a line where deposits in personal or business bank statements stand in for tax returns as proof of income.

CLTV: Combined loan-to-value is all liens on the property, the existing mortgage plus the new line, divided by the property’s current value.

ADU: An accessory dwelling unit is a second, smaller living unit on the same lot, such as a garage conversion, a basement unit or a detached backyard unit.

Draw period: This is the window when you can borrow against the line, usually with interest-only payments.

How Is the Maximum Line Calculated?

The line comes from one equity formula: current value times the CLTV ceiling, minus the existing mortgage balance, capped at the program’s maximum line. Credit tier and occupancy set the ceiling. The dollar cap sits on top.

Work it in percentages. Say a primary residence has a first mortgage equal to 50% of its value, and the borrower sits in the 720+ tier at a 90% ceiling. The room under the ceiling is 40% of the home’s value. The $500,000 cap for that tier may bind before the formula does on a higher-priced home. Now take the same home with a 700 score. That tier reaches 85% on lines up to $500,000, so the room shrinks to 35% of value.

Equity is the simple version of the story. Lenders also look at credit, debt-to-income and the property itself. The Federal Trade Commission says the amount you can borrow depends on your income, your credit history and the market value of your home. That last item is the part ADU investors miss. A unit that does not exist yet has no market value.

What Do the Network’s Ceilings Look Like by Occupancy?

The ceiling depends on how the home is used. Across the wholesale programs Lendmire brokers, an investment property tops out at 70% CLTV, while a primary residence or second home reaches 90% only at 720 or better. Always read the ceiling for your own occupancy.

The tiers step down from the top. On a primary residence, 700 to 719 reaches 85% up to $500,000, 640+ reaches 80%, 620+ reaches 70% up to $400,000, and 600+ reaches 60% up to $400,000. On a second home, 700 to 719 reaches 85%, 660+ reaches 80%, and 640+ reaches 75%, all up to $500,000. On an investment property, both the 720+ and 700+ tiers sit at 70% up to $500,000.

Two caveats matter for the ADU decision. A primary-residence line above $500,000 needs 700 or better (720 on the longer-runway, five-year-draw program), tops out at 75% CLTV and requires a full appraisal. And a Texas primary residence is a homestead, so it caps at 80% combined regardless of the matrix.

Market surveys paint a wider picture. Experian reports that most HELOC lenders cap CLTV at 85%, and some go to 90% or even 100%. That describes the broader market. On this network, an investment property tops out at 70%, and the 90% figure exists only for primary residences and second homes at 720 or better.

What Does a Bank Statement Change, and What Does It Not?

A bank statement changes the income test. It does not change the equity test. The file runs on two separate checks, and the smaller of the two numbers sets what you can borrow.

The income side works like this on most bank statement programs:

1. The borrower supplies a window of personal or business statements, typically 12 to 24 months, depending on the program.

2. The lender analyzes the deposits. It does not simply add them up. Business-account deposits usually get an expense factor, and the program sets that factor. A CPA or tax-preparer letter may support a different one.

3. The resulting income is tested against debt. Debt-to-income tops out at 50% on these programs, 45% for credit profiles from 600 to 679, and anything above 45% needs a 680 minimum.

4. The new line is qualified on the interest-only payment calculated on the maximum draw, not only the amount you plan to use.

That last point trips up ADU borrowers. A $400,000 line you only plan to draw half of is still tested as if fully drawn. Size the line for the budget you need, not the largest one you can get.

Does the Finished ADU Raise the Line?

No. A home equity line is sized from the property as it stands today, and the future unit and its rent do not add borrowing power. Construction and renovation loans look at after-completion value, and a HELOC does not. Neighbor’s ADU financing overview draws the same line between current-value products and future-value products.

Valuation on these lines is lighter than most investors expect. Lines at or below $500,000 ordinarily run an automated valuation with no traditional appraisal, though a higher CLTV may call for a secondary valuation. A full appraisal is required on every line above $500,000, and a borrower can request one in any case. Either way, the value that counts is the home before the build.

The appraisal side also matters at the back end. One BiggerPockets thread describes a $100,000 ADU build that appraised closer to $50,000. That is one investor’s example, not a market statistic. It still shows why you should not count on the finished unit to refill your equity. A finished unit may support a higher appraised value, depending on comps and underwriter review.

Which Home Is the Collateral?

The line attaches to the existing property, and title is the first gate. Fee simple or leasehold title must sit with the individual borrower or an inter vivos revocable living trust. An LLC, corporation, partnership, or an irrevocable, blind or land trust cannot hold title on these lines. That is the sharpest structural difference from a DSCR loan, and a property already deeded to an LLC needs a vesting change or a different product.

Property type also screens files. Single-family homes, 2-4 units, PUDs, townhomes and condominiums, including non-warrantable condos, are eligible. Manufactured homes, co-ops, condotels, log homes, and commercial, mixed-use or agricultural-zoned properties are not offered. Modular factory-built homes are eligible on the longer-runway program only.

For an investor with several rentals, the exposure limits matter as much as one property’s equity. A borrower is limited to three lines. Combined exposure caps at $2,000,000 on one program and $750,000 on the other, and a borrower with more than 15 financed properties is not eligible. Availability is also narrower than the DSCR footprint. These lines are offered in Lendmire’s 16 full-service states: AL, CA, CO, FL, GA, IN, MI, MT, NM, NC, OH, PA, TN, TX, VA and WA.

How Do Draws Work When the Build Is in Stages?

Construction spending arrives in stages, but these lines front-load the draw. At least 75% of the line is drawn at closing on both wholesale programs. After that, a minimum subsequent draw of $1,000 applies on the program that states it, and $4,000 in Texas.

Two draw structures exist on primary residences and second homes:

• A 3-year interest-only draw followed by a 17-year fully amortizing repayment.
• A 5-year interest-only draw followed by a 25-year fully amortizing repayment.

Tennessee shortens both, to 3 years/12 years and 5 years/10 years. Investment lines use the 5-year draw and 25-year repayment structure only. Pricing floats through both periods and never converts to fixed.

This changes the planning. A staged ADU budget does not match a staged draw. If your plan needs funds released as phases finish, a construction or renovation product may fit better. If you want the cash on hand to pay contractors, a standalone line can work, and you carry interest on at least 75% of it from the start.

Payoff on sale is another point from the CFPB’s HELOC booklet. It says that if you sell, you are generally required to pay off the HELOC in full. Interest-only payments during the draw period are common, and the booklet notes some plans allow them.

What If the ADU Budget Is Larger Than the Line?

Then the formula, not the borrower’s appetite, sets the ceiling, and the plan needs a second source or a different product. Three paths come up in practice.

Run a thin-equity case. A primary residence with a 700 score sits at an 85% ceiling. If the first mortgage already equals 80% of value, only 5% of value is left. That is probably too little for any real build. A cash-out refinance on the first lien, or a construction product, may fit better.

Run an investment-property case. The ceiling is 70% CLTV. A rental with the first mortgage at 55% of value leaves 15% of value, and the $500,000 cap may not bind at all. An investor with several rentals may have more room on a different property.

Run a high-equity case. A primary residence at 720+ with the first mortgage at 40% of value leaves 50% of value under the ceiling. For most homes that leaves the $500,000 cap as the real limit.

One way to size it: compare the quoted ADU budget with the equity room as a percentage of value. If the room covers the budget with a margin, the line fits. If it does not, adjust the budget, the product or the property. For a plain-language comparison of the two main equity routes, see Lendmire’s piece on how a bank statement HELOC differs from a bank statement cash-out refinance for an ADU.

Where Does a DSCR Loan Fit After the Unit Is Built?

A DSCR loan fits after the unit is leased, not before. DSCR compares rent to the full monthly payment, and an unbuilt ADU has no rent to compare. Once the property produces documented rent, a DSCR cash-out refinance can replace the line. Cash-out leverage on a standard rental tops out around 75% LTV across most of the network, with about 6 months of seasoning commonly expected.

DSCR coverage of 1.00 is where select programs start. It is not the standard everywhere. A separate select-lender path takes coverage below 1.00, with leverage and terms adjusted. Clearing 1.00 does not mean positive cash flow, because repairs, vacancy, management and capex sit outside the calculation. The complete DSCR loans guide walks through the coverage math.

Before planning that exit, run the refinance test on the finished property. Loans tied to title in an LLC are handled differently under a DSCR loan, subject to lender program eligibility. A line that matures into a repayment period still has to be paid off or refinanced out.

Common Mistakes on ADU Equity Lines

• Sizing from future value. The line uses today’s value. Budget as if the unit adds nothing to the formula.
• Ignoring the draw rule. At least 75% of the line is drawn at closing, so the carrying cost begins on day one of the line.
• Using the wrong occupancy ceiling. A rental and a primary residence follow different tiers, and a top-tier ceiling does not apply to both.
• Holding title in an LLC. These lines require the individual or a revocable living trust on title.
• Treating bank statements as no underwriting. The file is reviewed on documented income under the applicable program, subject to lender guidelines.
• Skipping the take-out plan. The line is not permanent financing, and the exit depends on the appraisal and the lease.

A broker can match a scenario to a program because the wholesale network includes several lenders with different tiers, structures and overlays. The best program for your situation depends on occupancy, credit profile, leverage need and how the income is documented.

If you are considering a home equity line and want to see how the numbers work, Lendmire can help you compare HELOC options based on the property, the equity available, credit profile, combined leverage, and your goals. Lendmire is a mortgage broker, not a lender, and every figure is subject to lender guidelines and full file review.

About Lendmire

Lendmire (NMLS# 2371349) is a mortgage brokerage serving homeowners and real estate investors in its 16 full-service states. Home equity lines of credit are arranged through wholesale lending channels; Lendmire brokers the line and the lender underwrites each application under its occupancy-based guidelines. Scotsman Guide named Lendmire a Top Mortgage Workplace in both 2025 and 2026.

References

1. FTC – Home Equity Loans and Home Equity Lines of Credit

2. Experian – How Much Can You Borrow with a HELOC

3. Neighbor – ADU Financing Options

4. BiggerPockets – HELOC for ADU exit strategy

5. CFPB – HELOC booklet