How an Investment Property HELOC Works to Build an ADU on a Texas Homestead

The Quick Read: The title describes two different loans, and the file turns on which one you mean. One option is a line on the homestead itself, which Texas treats as a constitutional equity loan. The other is a line on a separate non-homestead rental whose proceeds pay for the ADU. Each has its own collateral rules, its own leverage ceiling, and its own take-out path.

• A line on a Texas homestead is capped at 80% combined loan-to-value (CLTV), and the lender sizes it on the home’s value today, not its value after the ADU is built.
• A line on a Texas investment property is a separate product. Across the wholesale network it tops out at 70% CLTV, requires a 700 credit profile, and carries a $500,000 maximum line.
• Neither line is qualified on projected ADU rent. Equity, credit, occupancy, and combined leverage decide the file.
• A DSCR loan can take out the project later only if the property is no longer the owner’s homestead.

Key Terms Defined

HELOC: A revolving home equity line of credit with a draw period, then a repayment period, secured by a lien on real estate.

CLTV (combined loan-to-value): All loans secured by the property, added together and divided by the property’s value.

Homestead: The Texas owner’s primary residence, which carries constitutional protections that limit how it can be borrowed against.

Non-homestead: A rental, investment property, or second home that the owner does not occupy as a primary residence.

ADU: An accessory dwelling unit, a second small living unit on the same lot, either detached or built into or onto the main house.

DSCR: Debt service coverage ratio, the property’s monthly rent divided by its monthly principal, interest, taxes, insurance, and any HOA dues (PITIA).

Two Readings of the Title

Both readings are legitimate, but they sit on different collateral. Sorting them out first keeps you from applying homestead rules to a rental, or the reverse.

The Texas A&M Real Estate Research Center explains that Section 50(a)(6) of the Texas Constitution sets the requirements for homestead equity loans. It also states that these loans may not be taken out on a secondary residence or a rental. That is why a rental line is a different product rather than a variation on the same one. Across the wholesale network, Texas second homes and investment properties are eligible as non-homestead transactions.

How a Homestead Line Is Sized

A homestead line is sized by subtracting existing liens from a capped share of the home’s value on the day the line is established. The result is the most room the line can have, before credit, debt-to-income, and the lender’s own tests narrow it further.

Run it as a percentage exercise. Say the homestead carries a first mortgage equal to 55% of its value. The 80% cap leaves room for a line worth up to 25% of value. If the first mortgage is 70% of value, only 10% of value is left. The same arithmetic on a rental uses 70% instead of 80%, and the line cannot exceed $500,000 whatever the equity shows.

The appraisal values the property as it stands, not as it will stand with an ADU. A BiggerPockets thread on ADU financing has an investor reporting that lenders will lend against current equity through a second mortgage or HELOC rather than against the post-build value. That matches how network lenders size lines. An ADU may support a higher appraised value later, depending on comps and underwriter review, but the line cannot borrow against value that does not exist.

For an investment line at or under $500,000, valuation usually runs on an automated model, and a traditional appraisal is commonly not ordered. A borrower can still request a full appraisal. Homestead lines above $500,000 require one.

The Sequence, Step by Step

1. Decide which property carries the lien. Equity in the homestead and equity in a rental are separate pools. The Texas A&M center notes a homestead equity loan may not be secured by any other real or personal property, so a rental cannot be added to a homestead line as extra collateral.

2. Check for a prior equity lien on the homestead. Texas allows one Section 50(a)(6) loan on a homestead at a time. A prior homestead cash-out refinance is also a Section 50 loan, so a homestead line spends that one slot. A primary-residence line also carries 12-month seasoning and a mandatory waiting period between application and closing. These bind primary residences only, not rentals.

3. Size the line on today’s equity. Take 80% (homestead) or 70% (rental) of current value, subtract existing liens, and compare the result to the program maximum and to the ADU budget. If the budget exceeds the line, the gap is cash.

4. Confirm eligibility. On an investment line the network wants a 700 credit profile, with debt-to-income up to 50%. Title must be held by the individual borrower or a revocable living trust. An LLC cannot hold title on these lines, and a rental already deeded to an LLC needs a vesting change or a different loan. Texas properties are limited to 10 acres, and a property listed for sale, or within the past 60 days, is ineligible in Texas.

5. Close, then draw. At least 75% of the line is drawn at closing on the wholesale programs. After that, Texas requires each additional draw to be at least $4,000. The Office of Consumer Credit Commissioner confirms that figure under Section 50(t)(2). The same guidance says a homestead equity loan must close at the office of the lender, an attorney, or a title company.

6. Pay contractors under a compliant written contract. The next section covers this step in detail.

7. Plan the take-out. The line floats, and an investment line runs a 5-year interest-only draw followed by a 25-year repayment period. Decide before you build whether you will pay it down, refinance it, or hold it through repayment.

The 75% draw at closing matters for an ADU. Construction spends money in stages, but most of the line is drawn and accruing interest on day one. Borrowers who need a slow draw schedule should say so before choosing the line size.

The ADU Contract and the Contractor Lien

The funding source and the construction contract are separate legal questions, and the second one binds the homestead no matter how the build is paid for. Section 50(a)(5) allows a lien on a homestead for new improvements, but only if the work is contracted in writing. A Fasthoff Law Firm article on constitutional liens describes that requirement. On a family homestead, both spouses sign.

The stricter rules sit on renovation. A compliance overview of Texas residential construction says the fifth-day waiting period and the 3-day right of rescission apply to remodeling existing improvements but not to constructing new ones. It also says the contract must be filed with the county clerk.

That creates a classification question. A detached ADU is new construction. A garage conversion or an addition attached to the house looks more like a renovation of existing improvements, and the stricter rules plausibly apply. Treat the classification as something to confirm with a Texas title company or attorney before the contract is signed, not something to assume.

Permits are a second gate. Texas has no single statewide ADU law, so city rules decide whether the unit can be built and rented. An ADU that cannot be legally rented cannot support rent in a later lender review.

Where the Rule Breaks

Several situations change the answer, and each is easy to miss:

• The funds and the collateral are different questions. Borrowing against a rental and spending on the homestead is not a homestead lien problem, because the lien sits on the rental. Lenders can still restrict how proceeds are used on investment lines, so confirm purpose-of-funds terms before relying on that route.
• A co-owner can create homestead status. Doss Law’s Texas homestead guide explains that signing a non-homestead affidavit does not waive homestead protections. It also says that if a co-owner treats the property as a homestead, the property is considered homestead even if that person is not a borrower.
• An earlier modification can count as one transaction. The OCCC guidance treats a home equity loan and a later modification as a single transaction in some cases, so a modification does not reset the one-loan clock.
• A prior cash-out refinance blocks a new line. An investor who already used the Section 50 slot has no second one available.
• An unpermitted ADU supplies no usable rent. A lender will generally not count rent from a unit that has no permit.
• Some structures are not eligible collateral. Manufactured homes are not eligible on these lines. Modular homes are eligible on one of the wholesale programs only.
• Exposure limits apply. A borrower is limited to three lines, and an owner of more than 15 financed properties is not eligible.

Sequencing advice on BiggerPockets, such as funding with a HELOC and refinancing into a 30-year loan after the build, gets harder in Texas. A BiggerPockets thread on ADU build and hold describes that plan, but on a Texas homestead the refinance is itself a Section 50 transaction.

Where DSCR Fits

A DSCR loan is the take-out tool for the rental side, and it applies only to a non-owner-occupied investment property. Because these are business-purpose investor loans, they are reviewed differently from a standard owner-occupied mortgage. If the ADU property is still the owner’s homestead, a DSCR loan is not available on it. If the owner moves out and the house becomes a rental, the homestead question changes, and a Texas attorney or title company should confirm that status first.

When the property does qualify as a rental, the numbers work as follows. Qualification runs primarily on property-level rental income covering the payment, subject to lender guidelines. The appraiser typically reports market rent on Form 1007 for a single-unit property or Form 1025 for a 2-4 unit property. A house plus a legal, separate ADU can shift the file toward the multi-unit form, depending on the lender and the appraiser.

Across the wholesale network, a few program ranges frame the take-out:

• Cash-out refinances on standard rentals top out around 75% LTV, with about 6 months of seasoning as the common expectation. Short-term rental collateral is lower, at 70%.
• Coverage of 1.00 is where select programs start. A separate select-lender path goes below 1.00, with leverage and terms adjusted. Stronger ratios open better pricing and leverage.
• Most programs want around a 660 score, a 620 floor exists in parts of the network, and 700 and above reaches the highest leverage tiers.
• Reserves vary by lender, leverage, loan size, and transaction type, commonly around 6 months of PITIA.
• Loans reach up to $3,000,000 on standard programs, with smaller balances available through select lenders. Most are 30-year fixed, and extended terms and interest-only periods are available through select lenders.

Clearing 1.00 does not mean positive cash flow. DSCR compares rent to PITIA only, and repairs, vacancy, management, utilities, and capital expenses sit outside the ratio. The complete DSCR loans guide walks through the calculation in detail.

What the Decision Looks Like

The three paths below differ most on collateral and on what happens after the build:

A homestead line is usually the largest pool of equity, but it spends the one Section 50 slot and carries the constitutional contract rules. A rental line avoids those homestead rules but is capped at 70% CLTV and $500,000. A DSCR cash-out on the rental is fixed-term and is reviewed on rent, so it suits owners with an eligible rental, enough equity, and no need for revolving access.

Two more points belong in the budget. An ADU may return less in appraised value than it costs to build, so the equity in the finished unit may not replace what the line spent. And the line floats during both the draw and repayment periods, so the carrying cost during construction is not fixed.

Next Step

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. Programs described here are subject to lender guidelines and full file review, and nothing here is a commitment to lend.

About Lendmire

Lendmire — NMLS# 2371349 — is a mortgage broker that arranges home equity lines of credit in its 16 full-service states through wholesale lenders, on primary residences, second homes and investment properties. Every line is subject to the lender’s guidelines and full underwriting. Scotsman Guide named Lendmire a Top Mortgage Workplace in both 2025 and 2026.

References

1. Texas A&M Real Estate Research Center, “What to Know About Home Equity Loans in Texas”

2. BiggerPockets, ADU build and financing thread

3. Texas Office of Consumer Credit Commissioner, home equity guidance

4. Fasthoff Law Firm, constitutional versus statutory liens in Texas

5. Compliance Pathways, Residential Construction

6. Doss Law, Texas Homestead Protections

7. BiggerPockets, ADU build and hold thread