Key takeaways

  • Detached structures (garages, sheds, carports, ADUs) can enhance your home’s fair market value, especially if they increase the usable or liveable space.
  • A detached structure can be financed via a HELOC, home equity loan, cash-out refinance, personal loan, renovation loan or credit cards.
  • There are pros and cons to each financing option, based on the interest rate, your home equity stake and other factors.
  • Costs to add a detached structure can vary widely, depending largely on size, features and whether they require professional labor.

Detached structures are a great way to add space and value to your home. Whether it’s a workshop, storage space, garage or accessory dwelling unit (ADU), the presence of a detached structure to your property could positively impact its worth.

While the long-term benefits are great, detached structures are expensive to build. If you do not have the funds to pay upfront, there are financing options available. Let’s look at the ins and outs of these add-ons.

Should you borrow to finance a garage or detached structure?

You can, of course, pay for your detached structure in cash, but considering that they can cost well into the five figures — even up to $110,000 in some elaborate cases — that might not be the most feasible option.

Some scenarios when it might make sense to finance your detached structure project include:

  • If you don’t have all of the cash needed to pay the full cost of the project.
  • If you have equity in your home that can be tapped to fund the project.
  • If you have a solid credit score and will be able to obtain a competitive interest rate on a loan.
  • If you have a plan to pay back the money and are disciplined about doing so.

How to finance your additions

Fortunately, there are plenty of ways to finance your addition that can be budget-friendly. Many personal loans come with repayment terms of one to 10 years, while home equity loans and HELOCs could have repayment periods of up to 30 years. With both options, you’ll be responsible for making consistent monthly payments or risk the health of your credit score. Bear in mind, you’ll be paying back interest on top of your loan amount.

HELOCs

Home equity lines of credit — or HELOCs — can be a good way to finance a detached structure or any home improvement. HELOCs give you a line of credit to pull from (essentially like a credit card) based on the amount of equity you have in the home. You usually have 10 years to borrow from your line, and you’ll repay what you borrowed (plus interest) over the following 20 years or so.

Keep in mind that HELOCs have variable interest rates — they reflect moves by the Federal Reserve to raise or lower rates — so the amount of interest you pay could rise over time.

A HELOC could be a good option if:

  • You have great credit that allows you to score the best possible interest rate.
  • You have substantial equity in your home.
  • You don’t know exactly how much money you need for your project or how long it’ll take to do.

A HELOC could be a bad option if:

  • Your income isn’t reliable, and might not be able to handle a monthly obligation.
  • You plan on selling your home soon, which requires paying off your credit line immediately.
  • You don’t have strong credit.

Home equity loan

Like a HELOC, a home equity loan uses the equity you’ve built up in your home. However, a home equity loan is an installment loan, meaning you receive all of your funds at once and repay it in equal monthly installments.

Typically, the loan amount you can borrow is no more than 80-85 percent of your home equity. You’ll have to start making payments right away, but your interest rate and the monthly payment will never change.

A home equity loan could be a good option if:

  • You need all of your funds upfront and/or you know the exact amount you’ll need.
  • You have substantial equity in your home.
  • You prefer fixed monthly payments.

A home equity loan could be a bad option if:

  • You don’t have at least 80-85 percent equity in your home.
  • Your financing needs change throughout the construction project.
  • You don’t have strong credit.

Cash-out mortgage refinance

A cash-out mortgage refinance is the process of replacing your existing home mortgage with a new, bigger mortgage, then taking out the difference in cash. You can use this cash for any purpose.

Keep in mind, a cash-out refinance completely replaces your existing mortgage and may change your repayment timeline or monthly payments. It’s generally best to do this only if you can get a  lower rate on your mortgage, or improve the terms in some other way.

As with your original mortgage, your monthly payments will be steady (assuming you opt for a fixed-rate loan). “In this way, the cash-out refi provides protection from rising rates in the future, which is an advantage over a HELOC,” says Glenn Brunker, president of Ally Home. The cash-out refi’s interest rates may be lower than those of home equity loans, too.

A cash-out mortgage refinance could be a good option if:

  • You can obtain a better interest rate than you currently have on your mortgage.
  • You want to revise or change your current mortgage terms.

A cash-out mortgage refinance could be a bad option if:

  • You don’t qualify for a lower rate than your existing mortgage loan.
  • You prefer to keep your current mortgage terms.

Personal loans

A personal loan can also be a solid option if you’re looking to add a detached structure to your property. The good thing about these loans (when compared to a home equity loan, for example) is that they don’t require collateral. And the proceeds from a personal loan can generally be made available very quickly, sometimes in as little as a few days.

The drawback, though, is that they typically have higher interest rates than home equity products. They also come with shorter terms than HELOCs, so you’ll likely need to repay the money faster.

The amount you can borrow for a personal loan (and the interest rate you’ll get on it) will depend largely on your credit score, income and other debts. So if your credit is less than stellar, you might consider financing your project another way.

A personal loan could be a good option if:

  • You don’t want to put your home on the line by using it as collateral.
  • You need the money quickly.
  • You have a solid credit score or a creditworthy co-signer.

A personal loan could be a bad option if:

  • You need to repay the loan over a longer period.
  • You don’t have strong credit, and so won’t get the most competitive rate.

Home renovation loans: FHA 203(k), Freddie Mac CHOICERenovation, Fannie Mae HomeStyle

Renovation loans can be good choices when looking to improve your home. Often these products are combination mortgages and loans: that is, they simultaneously provide financing both to buy a residential property and to renovate it — which includes building additions or new detached structures.

FHA 203(k) loan

One go-to is the Federal Housing Administration (FHA)’s 203(k) loan. Because they’re backed by the FHA, these loans come with low interest rates and aren’t too hard to qualify for.

The FHA also allows for 203(k) refinancing, which would allow you to refinance your existing mortgage into a 203(k) loan. This would give you the funds you need to pay for your improvements while also keeping you to a single monthly payment.

However, like all FHA loans, your property must meet minimum requirements to be eligible under a 203(k) refinancing loan. For example, the detached structure must meet the program’s list of eligible activities and your home’s value must be within FHA’s mortgage limit.

Freddie Mac CHOICERenovation Loan/Fannie Mae HomeStyle Renovation loan

There are also private sector loans for renovations and combo purchase/rehabs. The Freddie Mac CHOICERenovation loan is one that allows you to both buy and rebuild. The Fannie Mae HomeStyle Renovation loan or mortgage is another.

In general, these loans are designed for any home renovation or repair that is affixed to the property and adds value to it. Detached structures count, as long as they are permanent fixtures.

Fannie Mae and Freddie Mac may require tougher qualifications than a government-backed loan: higher credit scores, bigger down payments. For instance, Fannie Mae credit checks are fairly robust. Not only will the lender check your credit score, but also evaluate how often you carry a credit balance versus paying the balance off each month. You must complete renovations within 6 months (Freddie loans) or 12 months (Fannie loans) of approval.

A home renovation loan could be a good option if:

  • You’re buying a place that needs substantial rehabbing.
  • You want to refinance your existing mortgage.
  • You have your plans ready and are prepared to start renovations quickly.

A home renovation loan could be a bad option if:

  • Your home/property or construction project doesn’t meet the FHA loan requirements, or you don’t meet the lender credit requirements
  • You’re not ready to begin work within 30 days of closing.
  • The project is likely to exceed the designated time period for completion.

Detached structure cost expectations

The costs and expenses you’ll need to cover will depend on the specific detached structure you’re looking to build. While some structures cost as little as a few thousand dollars, others can run as high as $100,000 if you get all the bells and whistles.

Overall, the cost of each detached structure will depend on the following factors:

Here’s a little more about what you can expect with each type of detached structure.

Carports

If you don’t have a garage or just need extra space to store a vehicle, a carport can be an easy and affordable choice. They can also be helpful if you need a rain-protected loading zone for kids, elderly residents or family members with disabilities.

The biggest downside to a carport is that it might require permits from your city. These can be tedious and sometimes costly to obtain. You will also need to check with your homeowners association and read your deed restrictions to ensure that carports are allowed in your specific community.

Cost-wise, HomeAdvisor estimates a carport runs between $3,190 and $9,806, with an average price tag of about $6,436. Among the factors that can affect price are site preparation, unit size, permit costs and presence of a concrete slab. Fixr reports a similar range in the national price — $2,000 to $10,000 — with most folks forking over an average $8,439 for an installed 18’ x 18’ x 8’ galvanized steel carport on a 4” thick concrete slab with two walls.

Boat shelters, a related structure, will typically cost more due to their larger size and higher height.

Detached garages

Detached garages can serve many purposes: workshop, band studio or of course a place to store your car or anything else. In fact, the National Association of Home Builders’ “What Home Buyers Really Want” 2019 report found that 85 percent of homebuyers rank garage storage as a home feature they want most, and 36 percent consider it an essential feature for their future home.

Anticipate paying between $19,200 and $45,000 for a two-car detached garage, per HomeAdvisor, which estimates that the average cost per square foot will be $40 to $70. A one-car detached garage may set you back as little as $11,500 versus $31,000, which is the expected starting price for a three-car detached garage. Fixr calculates that the typical homeowner pays, on average, $52,830.).

Accessory dwelling units (ADUs)

An ADU represents a secondary form of housing built within or adjacent to your single-family home on the same lot. It can be attached or detached. The key point is that it’s an independent living space, with its own entrance, bathroom and kitchen facilities.

A detached ADU is likely going to be the most expensive structure you can add to your property. Expect to pay $100,000 and up to have a detached ADU built on your lot, based on HomeAdvisor data. Angi reports that an ADU costs, on average, $82,500, or around $150 to $300 per square foot, with a typically sized ADU measuring between 600 and 1,200 square feet.

Storage sheds and barns

Sheds and barns are also popular detached structures that can be used for both storage and personal space. A trend is the “she-shed” or “man-cave” addition, which offers residents a private at-home retreat — a grown-up version of a kid’s playhouse (another fun use of a shed).

The best thing about sheds is that they’re typically quite affordable. Most sheds span $1,500 to $10,000 in cost, according to HomeAdvisor, although a small prefabricated shed can cost as low as $300 versus a custom upscale shed that may ring up for at least $33,000. In general, most shed buyers pay between $4,000 and $6,000. Fixr, meanwhile, reports that the average cost runs $5,653 for a 10’ x 12’ shed — figure $50 per square foot for a custom build, though kits run about half that.

Got a barn in mind instead? (Traditionally, a barn was a structure to house livestock, but now there are mini-versions for suburbanites, which function more as storage units or additional rooms.) A barn will likely range from $20 to $150 per square foot, including labor and materials, HomeAdvisor indicates. The typical price span for a barn is $1,597 to $4,967.

The pros and cons of financing detached structures

As with any major purchase or expense, there are pros and cons to using a term loan to finance the project. Adding a detached structure to your property is no exception. Loans offer a lump sum windfall that make it easy to get started on an upgrade — but it may be wiser to in some cases to use savings or other types of debt.

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Pros

  • Several options offer better, cheaper ways to borrow, especially compared to credit cards.
  • You can reserve your savings, have cash available for other expenses.
  • Loan interest may be tax-deductible, if you itemize on your tax return.
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Cons

  • You have to meet approval requirements and qualifications.
  • Applying for a loan can be time-consuming and delay the start of your project.
  • The interest you pay can significantly increase the overall cost of your project.
  • You are incurring additional debt that can hurt your financial profile.

How to estimate your costs

The expense of building a detached structure depends on the size of the structure you hope to build, as well as the materials and finishes you select. Several home improvement sites can help you outline the materials your project will involve and what these items will cost. These sites detail how much a garage project may run you per square foot, as well as what you can expect to pay for permitting, roofing materials, drywall, framing, different types of garage foundations, siding materials and more.

Also significant: If you are using a prefab kit — easier if you’re doing it yourself — or aiming to construct from scratch.

If you decide to skip the DIY route and hire a contractor to handle your detached structure project, it’s important to have a firm understanding of what you hope to achieve, says David Steckel, a home expert with Thumbtack, a home renovation site and contractor search service.

“Do you want to have a small office space or do you want to create a new living area that can be rented out?” he asks. “This goal is translated by the general contractor into a scope of work budget, which provides an explicit, line by line, description of what work is going to be completed, a rough estimate as to what level of finish, and a cost for everything.”

When reviewing potential contractors, do background checks with the Better Business Bureau and check that the company has a contractor’s license. It’s also a good idea to obtain references from previous clients or read Yelp and Google reviews.

How much value can a detached structure add to my home?

It’s difficult to estimate what kind of return on investment you can expect by adding a detached structure to your home. But it’s safe to assume that a well-built garage, carport, shed/barn or ADU will increase your property’s value to some extent. Anything that enhances the living space or functionality of the property generally does.

Per Porch.com, a residence with an ADU located in the largest cities is typically priced 35 percent higher, on average, than a property without one.

When it comes to other types of detached structures, the extent to which they can increase your home’s value will depend on the size, quality and overall condition of the structure.

“Generally speaking, a new detached garage will probably add between 5 percent to 20 percent to a home’s value, while a major shed can add between 2 percent and 10 percent to a home’s value,” says Jasen Edwards, a real estate agent and chair of the AgentAdvice.com Agent Editorial Board in Austin, Texas. “Expect a new barn to add between 5 percent to 15 percent value versus 2 percent to 8 percent for a new carport.”

Cam Dowski, a Realtor and founder of WeBuyHousesChicago, says “adding a two-car garage to a house without one could add about $20,000 to the value of the home.”

Return on investment reflects the cost of a project, but the nature of the project itself is more important. Austin Beachy, who handles marketing at Sheds Unlimited in Morgantown, Penn., notes that a new shed can add decent value but not as much as a garage. “For example, if the cost to build a new shed is $10,000, it could add between $5,000 and $7,000, or 50 to 70 percent of the total building cost, to the value of your home,” Beachy explains. “A new garage, on the other hand, can provide a greater return on investment in the range of 60 percent to 80 percent of the cost of the garage’s construction.”

Bottom line on financing detached structures

Borrowing money to finance a detached structure could be a good idea if you have a plan in place to pay off your debt.

Fortunately, there are many ways you can borrow to build a garage, ADU, barn or shed. But it’s important to estimate your labor and material costs thoroughly to determine how much you need to borrow. Shop around to find the right contractors and materials, and compare bids carefully.

Do the same with your financing: It’s wise to shop around with a few lenders. Doing so will allow you to compare rates and find the cheapest way to finance your detached structure. With the right planning and preparation, you can better ensure a satisfactory outcome on the addition, while adding to the versatility and value of your property.

Additional reporting by Lara Vukelich