How Much Does It Cost to Build an Attached Garage?

In this guide

Attached Garage Cost per Square Foot

Technically, you could have your new attached garage built in any size you desire, but there are a few standard sizes. For a one-car garage, the average size is about 12 x 20 feet and has an average cost of around $18,000. The smallest size you can use for a two-car garage is approximately 20 x 20 feet, with an average price of $28,000. Most people find that 24 x 24 feet ($30,000 to $35,000) is more comfortable for two cars, provided you have the room. Consider increasing the depth of the garage to create more storage or a space for a workshop.

Attached Garage Prices by Size

The size of an attached garage will depend on many factors. These include how much space you have, how many vehicles you own, and what your needs are for storage or for a shop. The costs increase as the size increases.

1 Car Attached Garage Cost

A 1 car attached garage should have a minimum width of 12’ and a minimum depth of 20’. Consider making the garage wider or deeper to add more room for storage or for a workspace. Average costs for a 1 car attached garage will range from $18,000.

2 Car Attached Garage Cost

The minimum size for a 2 car attached garage would be 20’ x 20’. If you have large vehicles and will need more space for door clearance, or desire extra space for storage or other activities, consider increasing the footprint. Expect to pay around $28,000 for a 2 car attached garage.

3 Car Attached Garage Cost

Dimensions for those hoping to protect three cars will be at minimum 30’ x 20’. This is also a great choice for two cars and a workshop space. Consider adding extra depth for more flexibility. The cost for a 3 car attached garage will be around $34,500.

4 Car Attached Garage Cost

A 4 car attached garage will only be possible on a large piece of land. A common dimension is 40’ x 20’. Expect a 4 car attached garage to cost around $45,000.

RV Garage Attached to House Cost

RV’s come in many sizes. A 20’ x 44’ structure is a good size to contain most RV’s. Keep in mind that an RV garage will also have to be taller and have a bigger door. Expect costs to be around $52,000.

Attached Garage Siding Material Cost

The exterior of your garage walls also needs finishing. Because the garage is attached to the rest of your home, it is typical to use the same siding and trim material you have on the rest of your home to finish the garage. This produces the most cohesive look for the property and makes the garage look like it was built with the house, rather than as an add-on. This also means that any finish techniques, decorative trim, or accent material needs to be included on the garage’s facade as well.

When it comes to siding materials, you generally get what you pay for. Low cost materials such as fiber cement and vinyl will require more maintenance and not last as long. Metal siding is fire and insect resistant, but can dent easily and some types are prone to rusting. Higher cost materials such as stucco and stone will provide more natural insulation and will not need as much maintenance.

Typical materials and costs for siding, trim, and labor for a garage include:

Attached Garage Roofing Cost

Like the siding, your garage should ideally have the same roof as the rest of your home. This is especially important if your garage will have the same height as the rest of the property because the roofs are often joined for a seamless appearance. Switching materials suddenly at the garage can lower the curb appeal of the property.

Attached Garage Foundation Cost

Most garages have a slab foundation that doubles as the floor of the garage and costs between $6 and $12 a square foot. If you require heavier footings ² like for supporting a living space above the garage, then your costs can rise to $8 to $14 a square foot. For a 24 x 24-foot garage, expect the foundation to cost between $3,456 to $6,912 for a basic slab, labor included.

Labor Costs to Build an Attached Garage

Labor costs vary depending on the scope of the project and what phase it is in. An electrician’s fees differ from a contractor’s fees, for example, but on average, most people find that they spend around $20 to $30 a square foot on labor. This makes the price about $15,000 in labor out of the $35,000 total.

Attached Garage Insulation

Not all garages are insulated, but if you plan on using the space for more than your car, you may want to insulate it now. Costs will vary, depending on the type of insulation chosen and the difficulty of installation.

Attached Garage Door

Garage doors are an integral part of a new attached garage. While there are double garage doors, which uncover both cars at once, it is more common to have one door for each vehicle stored in the garage so that each has its own access.

Garage doors come in several materials, each of which has attributes to consider:

Steel

Steel is a good option if you are looking for a very strong, durable and heavy material. Keep in mind that it must be powder-coated to prevent rust. The cost for a steel garage door is $400-$2,000.

Vinyl

Vinyl is a very lightweight material, it is a good choice for your garage door because it is inexpensive, durable and does not require paint. Expect to pay between $600-$800 for a vinyl garage door.

Aluminum

As vinyl, aluminum is a lightweight material. Moreover, it resists rust and can be painted to look like wood. The cost for an aluminum garage door ranges between $800-$1,300.

Fiberglass

This material looks like wood and resists warping, moisture and insects. Expect to pay $1,500-$2,250.

Wood

Wood can be carved or milled into various styles. However, it must be painted or stained and requires frequent maintenance. You should pay $2,000-$2,800.

Attached Garage Designs

It is a good idea to work with an architect when designing an attached garage. An architect can help design the building to seamlessly attach to your existing home and can also help with the floor plan. A new architect will charge about $150 to $200 an hour, while an experienced architect will charge $350 to $400 an hour.

Designs will depend on what you want in the structure. Think about what you will use the garage for, simply parking cars or also as a workshop? Would you like a bathroom, a place for storage, or living space above? Every addition above a simple place to park cars will add costs to the project.

A modern approach could be a one car garage with a classy red door that matches the entry door. A small entryway could be located above the garage that leads out to a rooftop deck. This could give access from the house and provide a nice space to host a barbecue or enjoy a cup of coffee.

Cost to Build Attached Garage with Room Above

There are many reasons to consider adding a room above a new attached garage. It could be used as an apartment to rent for extra income or for a family member, a workshop, a man cave, storage, or a play space for the kids. There are many possibilities. If opting for an attached garage with living space above, with electrical wiring, plumbing, and bathroom, expect the cost to range between $180 and $210 per square foot for the upper room alone. This will bring the total cost for an attached one car garage with a room above to between $60,000 and $65,000. If it will be a basic room for storage, cost should be more in the $30,000 to $40,000 range.

Attached Garage Construction

The building process for an attached garage differs depending on the project size and scope, your home’s style, location, and finishing work. But most are constructed similarly.

The ground is cleared and leveled 12 so that the concrete pad 2 can be poured. A frame is laid, and the walls and roof are erected. At some point, an opening is cut into the existing home to connect it to the garage. There may be changes to the exterior of the house where it meets the garage, such as the removal of siding.

The interior walls are finished as much as desired. This may include installing insulation and drywall 10 or leaving them bare. Shelving may be installed, the electrical work is completed, and the floor is sealed or finished as desired.

The exterior of the garage is clad to match the rest of the home, and new trim may be installed where the new garage meets the existing house to make the transition look better. If there is no driveway currently, one will be constructed, and the new garage doors will be installed and hooked up. Any windows will also be installed, and the exterior and roof finished.

A new interior door will likely be installed from the garage to the home.

Excavation and Site Prep

Like any build, the construction area must first be cleared and prepped. This varies depending on the condition of the lot beside your home. If it is level and cleared, the excavation will be less invasive than if you need to clear and level the lot. Typically, excavation for a garage simply involves clearing the site of any landscaping and ensuring a level area for the foundation. This cost ranges from as low as $900 for a simple leveling ³ to $2,500 if you need to remove some landscaping first.

An attached garage needs access to your home. So, the project may have demolition costs, depending on whether your garage will be minimally attached or open fully into your home’s interior. These costs range from $1,000 to $5,000, depending on how much your current exterior needs to be altered.

Attached Garage Walls

After framing your garage, consider how the inside walls will be finished. Some people leave them unfinished and uninsulated because the garage is only used for storage. Others choose to insulate the walls or cover them with drywall. Doing so can make your garage more comfortable and provide more choices later for how you use the space, such as enabling you to install shelving, workspaces, and other options. Basic drywall ⁴ for an interior costs around $1,500 to $2,000, while insulation for new construction costs about $1,500, assuming fiberglass ⁵ batt insulation.

Utilities

When adding an attached garage, there is the benefit of being able to be wired with the home’s electricity, heating, and even plumbing if you desire. Most garages only include electrical work, however, which provides for wiring the garage door opener, installing lights, and at least one electrical outlet. It is possible to make your new attached garage into a full workroom, which would mean adding other utilities. Keep in mind that when you pull a permit for the new garage, each utility you add may require a separate permit, depending on the area where you live. So while you need a building permit and an electrical permit for most garages, you may also need a plumbing permit if you plan on having water in your garage. You will pay between $65 and $85 an hour for an electrician when building your garage and expect the wiring to take anywhere from 4 to 16 hours, depending on the scope of the job, for a total of $260 to $1,360 in electrical work.

Atacched Garage Flooring

Most garages have a concrete slab foundation, which doubles as the floor. Seal this floor or coat it in epoxy to help it last longer, at a rate of around $500. If you plan on parking your car in the garage, you may want to leave the flooring at that. However, if you plan on using it for other things, there are garage floor systems that create a rubberized, more comfortable floor. They start at approximately $3,000.

Garage Door Trim

Garage door trim protects the inside of your garage from dirt, bugs, water, wind, and snow. It is an important element of any garage door and can be basic or custom. Popular materials for garage door trim include vinyl, PVC composite, and wood. The materials used can match the garage door or other trim used on the house. Basic garage door trim consists of common materials found at any building supplier. It will cost around $4 per linear foot, which includes materials and installation. There’s also the possibility of having your door trim custom made. Custom garage door trim will cost around $8 per linear foot including installation and materials.

Attached Garage with Breezeway

A semi attached garage is connected to the house with a breezeway. This is a great option if you would like to have access to the house without exposure to the elements, but would still like the garage to be a separate space. Reasons to keep the garage separate could be to minimize noise or fumes in the garage from entering the house. It also leaves more options for specialty garages, such as those with an apartment or man cave above. Costs for an attached garage with breezeway will be similar to a detached garage, with the added cost of building the breezeway and providing entry into the house. The average cost for a two-car single story semi attached garage with a finished interior, asphalt shingles, vinyl siding, and a breezeway will be around $54,000.

Attached vs Detached Garage

An attached garage is not the only choice you have for storing your car. Detached garages are also a valid choice. When making the comparison between the two, most people like that an attached garage offers the convenience of not having to go outside to get to their car in inclement weather. However, detached garages are often considered safer because there is no exhaust or fumes that could enter your living area. Detached garages can also usually be expanded if there is space, while it may be more difficult to expand an attached garage without upsetting the footprint 3 of the home. Detached garages also give you more options to place the garage on your property and may work better for odd-sized lots. Attached garages may make the most of a small space. Both provide storage and improve the value and function of your property.

Attached vs Detached Garage Insurance

Standard homeowners insurance covers the home and all that is attached to it, including an attached garage. Homeowners insurance also covers other structures on the property, but usually at a lower rate of 10% of your dwelling coverage limit. This means that if your home is insured for $220,000, the most you could get if something happened to your detached garage is $22,000. However, you can talk to your agent about upgrading your policy to get better coverage for a detached garage at an additional cost of about $50 to $75 added to the premium. Adding an attached garage will not necessarily cost more when it comes to insurance, however your policy will likely go up because the value of your house has gone up. Be sure to update your policy anytime any changes or additions are made to the home.

Attached vs Built in Garage

Built-in and attached garages are both attached to the house, but the key difference is that a built-in garage is built right into the living area and has living space above that can be accessed from the rest of the house. It is not very practical to add a built-in garage to an already existing structure, but is commonly done during new construction. If adding a built-in garage, expect the costs to be that of an attached garage with living space above ($60,000 to $65,000) plus the added expense of creating an access point from the garage to the house and from the house to living space above the garage, which will add at least another $1,000.

Enhancement and Improvement Costs

Garage Organizer System

If you plan to use your garage for more than storing your car, you may want to invest in a garage organizer system for around $2,610 on average, which helps make the most of the space.

Battery Backup

Garage doors run on electricity. If the power goes out, you may find that you cannot open or close your garage door. A backup battery system can help. Adding this feature to a garage opener will add $50 to $100 to the cost of the unit.

Exterior Lighting

If you plan to come and go from the garage a lot, you may want to invest in exterior lighting for the area. This helps make the space safer and easier to navigate. Expect to pay around $3,500 to $4,500 on exterior lighting.

Gutters Installation

Your new garage should have the same gutters as the rest of your home to direct rainwater away from the structure. Without them, you could have softening or rotting of areas like the soffit and fascia. New gutters will cost around $500 to $2,400 installed.

Windows and Skylights

Not all garages require windows or natural light, but if you plan on spending time there, you may want to have some installed. New casement windows cost between $380 and $635 installed, while a new skylight costs between $650 and $3,800 installed.

HVAC Installation

If you plan to spend time in your garage, you may want to add an all-in-one heating and cooling unit for between $700 and $1,500. It is inadvisable to run ducts through your garage due to health risks from the fumes, so all-inclusive garage units are the best choice.

Adding a Door from House to Garage

You will need to install a door between your garage and home. Entry doors cost between $500 and $700 on average, with demolition and labor costs adding another $300 to $500.

Workshop Area

Garages can be used for many things, including workspaces. If you plan on using yours for this purpose, you may want to install shelving ($200 to $1,000), countertops ($500 to $3,000), cabinetry ($500 to $5,000), or other items that make the space more usable.

Second Driveway

You may need to pave a new or additional driveway to your garage to access it more easily. An asphalt driveway costs around $830 on average to build and another $2,000 to pave.

Painting Garage Walls and Ceiling Cost

If deciding to finish off the interior, paint is a great idea for protecting the walls and ceiling. Hiring a painter will cost about $40-$60 per hour.

Adding a Bathroom

A bathroom could be a very convenient addition to a garage. Expect costs to be around $12,000 for a half bathroom, $35,000 for a ¾ bathroom, or $47,000 for a full bathroom. Costs could be less if plumbing and electrical are already present in the garage.

Remodeling Terms Cheat Sheet

¹ Vinyl: A synthetic plastic made from ethylene and chlorine. Vinyl has many applications in the construction industry and it is widely used in sidings, window frames, roofing and gutters, among others

² Footings: A support for the foundation of a house that also helps prevent settling. It is typically made of concrete reinforced with rebar, but can also be made of masonry or brick. It is usually built under a heavier part of the house like a wall or column, to distribute the weight of the house over a larger area.

⁴ Drywall: Type of plasterboard, commonly used to build walls and ceilings, composed of gypsum that is layered between sheets of heavy paper

⁵ Fiberglass: Plastic that is reinforced with glass fibers. The fibers may be mixed randomly throughout the plastic, or come in the form of a flat sheet, or be woven into a fabric