Yes, but the lender decides how much of your equity counts

Most construction lenders will let you use equity in your current home as part or all of your down payment. The lender appraises your existing home, subtracts what you still owe on the mortgage, and counts the remaining equity toward your down payment requirement. However, not every dollar of equity converts to usable down payment money—lenders typically cap it at 80 to 90 percent of your home's appraised value, and some require you to keep a cash reserve on top of that.

The catch is that using equity this way usually means taking out a second mortgage, a home equity line of credit (HELOC), or refinancing your first mortgage before you close on the construction loan. You cannot simply tell the construction lender "I have $100,000 in equity" and have them count it without proof that you can actually access the money. The construction lender needs to see that the funds are either already in your account or committed through a formal loan document.

Key Takeaways

  • Construction lenders count home equity toward your down payment only if you can prove you can access it—usually through a second mortgage, HELOC, or cash-out refinance.
  • Lenders typically allow you to borrow against 80 to 90 percent of your home's appraised value, meaning not all of your equity is available to use.
  • You will need a current appraisal of your existing home and a clear title search before any lender will commit equity-based funds.
  • Taking out a second loan before construction begins means you will have two mortgage payments during construction, which affects your debt-to-income ratio and monthly cash flow.
  • Some construction lenders require you to close the equity loan before they fund the construction loan; others will do it simultaneously at closing.

How lenders calculate the equity you can use

A construction lender starts with an appraisal of your current home. If that appraisal comes back at $400,000 and you owe $250,000 on your mortgage, you have $150,000 in equity. The lender will typically let you borrow against 80 percent of the appraised value—in this case, $320,000. Since you already owe $250,000, you can borrow an additional $70,000 through a second mortgage or HELOC.

That $70,000 is what counts as your down payment contribution. If the construction loan requires a 20 percent down payment on a $500,000 project, you need $100,000 down. The $70,000 from your home equity covers part of it; you would need to bring $30,000 in cash from savings, investments, or other sources to meet the full requirement.

Some lenders are stricter and cap equity borrowing at 75 or 80 percent of value instead of 90 percent. A few require you to keep a cash reserve equal to three to six months of the construction loan's interest payments, which reduces the amount of equity you can actually draw. Always ask the construction lender upfront what percentage they allow and whether they have reserve requirements.

Getting the money before construction starts

You have three main paths to convert equity into cash: a second mortgage, a home equity line of credit, or a cash-out refinance of your first mortgage.

A second mortgage is a separate loan secured by your home. You borrow a fixed amount, receive it as a lump sum, and make monthly payments. The interest rate is usually higher than your first mortgage because the second lender is paid after the first lender if something goes wrong. Closing takes two to four weeks, and you will have a second monthly payment starting immediately.

A home equity line of credit (HELOC) works like a credit card backed by your home. You are approved for a maximum amount but only pay interest on what you actually draw. If you need $70,000, you draw it when you need it and pay interest only on that $70,000. HELOCs are useful if you are not sure exactly when you will need the money, but some have variable interest rates that can rise over time. Closing takes two to three weeks.

A cash-out refinance replaces your existing first mortgage with a new, larger one and gives you the difference in cash. If you owe $250,000 and refinance for $320,000, you walk away with $70,000 in cash. This resets your mortgage term and interest rate, which can lower or raise your monthly payment depending on current rates. Closing takes three to five weeks.

Timing: when you need the money in place

Most construction lenders require proof that you have access to your down payment before they issue the first draw of construction funds. This means you should have the second mortgage, HELOC, or refinance closed and funded before the construction loan closes—or at the very latest, on the same day.

Some lenders will allow you to close the equity loan and the construction loan simultaneously, with all three closings happening on the same day. This is convenient but requires tight coordination between your current lender, your new construction lender, and the title company. If any document is missing or any appraisal is delayed, the whole day can slip.

Other lenders require the equity loan to close first, sometimes weeks before the construction loan closes. This means you will have the second mortgage payment starting before construction even begins. If the construction project gets delayed, you could be paying two mortgages for months with no construction happening.

What happens to your existing mortgage during construction

Your first mortgage does not go away when you take out a construction loan. You keep making regular payments on it throughout construction. If you also took out a second mortgage or HELOC to fund your down payment, you will be making payments on that too. The construction loan itself typically does not require full monthly payments during construction—you usually pay only interest on the amount drawn so far, and the full loan converts to a standard mortgage (or you refinance) once construction is complete.

This three-loan situation affects your debt-to-income ratio, which is what lenders use to decide whether you can afford the total monthly payment. A construction lender will calculate your debt-to-income based on your first mortgage payment, your second mortgage or HELOC payment, and the estimated interest-only payment on the construction loan. If that total is more than 43 to 50 percent of your gross monthly income (the threshold varies by lender), you may not be approved, or you may need to bring more cash down to reduce the construction loan amount.

Risks of using equity as down payment

Using home equity as down payment puts your current home at risk if the construction project runs over budget or if you cannot make payments. If you borrow $70,000 against your home and the construction costs balloon by $50,000, you now owe more than you planned on both your first and second mortgages. If you cannot pay, the lender can foreclose on your home.

Construction projects also frequently take longer than planned. If you are making payments on a second mortgage during a 12-month construction period that stretches to 18 months, you are paying thousands of dollars in extra interest and principal on a loan that was supposed to be temporary. Some construction loans have built-in contingencies for delays, but not all.

If your home's value drops between the time you take out the equity loan and the time you close on the construction loan, you may end up owing more than your home is worth. This is rare in stable markets but possible during downturns.

Alternatives if you do not have enough equity

If your home does not have enough equity to cover your down payment gap, you have other options. Some construction lenders accept a lower down payment (10 or 15 percent instead of 20 percent) if you pay mortgage insurance. Others will let you use a gift from a family member as down payment, though you will need a signed gift letter stating the money does not have to be repaid. A few lenders allow you to use funds from a retirement account (usually a 401(k) or IRA) without penalty if you meet certain conditions, though this is less common and comes with tax implications.

You can also delay construction and save cash for a larger down payment, which reduces how much you need to borrow and lowers your monthly payment. This is slower but avoids taking on a second loan.

Frequently Asked Questions

Do I have to pay off my first mortgage before I can use equity for a construction down payment?

No. You keep your first mortgage and add a second loan (second mortgage, HELOC, or refinance) on top of it. You will make payments on both during construction. Some lenders require your first mortgage to be in good standing with no late payments in the past 12 months.

What if my home has not been appraised recently?

The lender will order a new appraisal, which costs $300 to $600 and takes one to two weeks. You pay this fee upfront. If the appraisal comes back lower than you expected, your available equity shrinks, and you may need to bring more cash to the table.

Can I use a HELOC if I am not sure how much I will need?

Yes. A HELOC lets you draw only what you use and pay interest only on that amount. However, some HELOCs have variable rates that can rise, and some have annual fees. Ask whether the rate is fixed or variable and whether there are fees for opening or maintaining the line.

What if the construction loan closes before the equity loan?

This should not happen—most construction lenders will not fund until they see proof that your down payment is in place. If it does happen, contact your construction lender immediately. You may be in breach of your loan agreement, and the lender could delay funding or demand immediate repayment.

Does using equity as down payment affect my credit score?

Yes, temporarily. Opening a new loan (second mortgage or HELOC) triggers a hard inquiry and adds a new account to your credit report, which can lower your score by 10 to 20 points for a few months. Your score usually recovers within six months if you make on-time payments.