Why renovation is the special case

Among all the reasons people borrow against their homes, renovation occupies a genuinely different category — and not for sentimental reasons.

It is the only common use of home equity where the borrowing may be tax-advantaged, because the tax code treats money spent improving the property securing the loan differently from money spent on anything else. Every other popular use — consolidating credit cards, paying tuition, covering a medical bill, buying a car — falls outside that treatment.

That distinction is worth understanding precisely, because it is frequently described incorrectly.

The tax rule, stated correctly

IRS Publication 936 is unambiguous:

"Interest on home equity loans and lines of credit are deductible only if the borrowed funds are used to buy, build, or substantially improve the taxpayer's home that secures the loan."

Three conditions have to hold at once:

  1. The funds must be used to buy, build, or substantially improve the property. Routine repair and maintenance generally do not qualify. Replacing a failed water heater with a comparable unit is maintenance. Adding a bathroom, finishing a basement, or replacing a roof as part of a substantial upgrade is a different matter.
  2. The improvement must be to the home that secures the loan. Borrowing against your primary residence to renovate a rental you own elsewhere does not satisfy this.
  3. You must be within the overall limits. Deductible mortgage interest applies to the first $750,000 of qualifying debt ($375,000 if married filing separately), or $1 million ($500,000 if married filing separately) for debt incurred before December 16, 2017.

One point that trips people up: this is not a rule that expired. It was originally enacted under the 2017 Tax Cuts and Jobs Act with a scheduled sunset, and a great deal of online content still describes it as temporary. The One Big Beautiful Bill Act (Public Law 119-21), signed July 4, 2025, made the home-equity provisions permanent. Publication 936 now states the rule flatly — "no matter when the indebtedness was incurred" — with no expiration attached.

This is general information, not tax advice. Whether your specific project qualifies as a substantial improvement is a determination to make with a qualified tax professional, not with a lender and not with an article. Our fuller treatment is in Is HELOC Interest Tax Deductible?.

Match the financing to the payment schedule

Here is the practical argument for a line of credit over a lump sum, and it has nothing to do with interest rates.

Renovations do not get paid for all at once. A typical contract runs on a draw schedule: a deposit at signing, progress payments at defined milestones, a final payment at completion. A kitchen might run deposit → demolition → cabinetry delivery → installation → punch list, spread across four or five months.

A lump-sum loan hands you the entire amount at closing and begins charging interest on all of it immediately. The money then sits in your checking account waiting for the next milestone, costing you interest the whole time.

A HELOC charges interest only on what you have actually drawn. You draw to pay the deposit, then draw again at each milestone. The balance — and the interest — tracks the project instead of leading it.

Over a five-month renovation with staged payments, that difference is real money, and it is entirely independent of which product has the better rate.

The overrun reality

There is a second, less obvious advantage.

Renovations exceed their budgets with enough regularity that it is closer to a rule than an exception. Walls come open and reveal knob-and-tube wiring. A subfloor turns out to be rotted. A permit inspection requires bringing something unrelated up to current code.

If you financed with a lump sum sized exactly to the original quote, an overrun means a second financing event — a new application, new costs, and delay while the project sits.

A line of credit sized with deliberate headroom above the quote absorbs this. You are not obligated to draw the headroom, and you pay nothing for the portion you never touch. It functions as project insurance that costs nothing unless used.

What lenders look at

Home equity borrowing is underwritten primarily against the property and your capacity to repay. Expect a lender to evaluate:

  • Combined loan-to-value (CLTV) — your first mortgage balance plus the requested line, measured against the property's value. This is the constraint that most often determines the size of the line.
  • Property value — established through an appraisal or an accepted automated valuation, depending on the loan and the lender's requirements.
  • Credit profile — history and score.
  • Capacity to repay — verified through documentation appropriate to how you earn. If you are self-employed, see Getting a HELOC When You're Self-Employed.

Note what is generally not part of this: your contractor's plans, your design choices, or your renovation budget. Home equity financing is not a construction loan. The lender is lending against the equity that exists today, not against the value the project is expected to create. If your project depends on after-improvement value, that is a different product and a different conversation.

Before you draw the first dollar

Get the full scope quoted, not the starting scope. Size the line against the realistic total, including the contingency you would rather not think about.

Keep documentation of what the money paid for. If you intend to treat the interest as deductible, the burden of substantiating that the funds went to a qualifying improvement is yours. Keep contracts, invoices, and payment records. Your tax professional will want them, and so will the IRS if asked.

Understand your draw period and what follows it. A HELOC typically has a draw period during which you can borrow and make interest-only or minimum payments, followed by a repayment period during which the balance amortizes. Know both dates and know what your payment becomes at the transition. This is the single most under-read term in the document.

Don't finance a want as though it were an investment. Some renovations return a meaningful share of their cost at resale; many return considerably less, and enjoyment is a legitimate reason to do a project. Just be clear with yourself about which one you're doing, because it changes how much borrowing is sensible.