How much does it cost to finish an attic?
$50 – $150 average cost per square foot
$15,000 – $75,000 average total cost to finish
Average cost to finish an attic
The cost to finish an attic is $50 to $150 per square foot total on average. The cost of finishing an attic depends on the purpose of the finished space. Attic conversion costs $20,000 to $80,000+ to create a living space or $5,000 to $20,000 to finish an attic for storage.
|Finished attic square footage||Average total cost|
|100||$5,000 – $15,000|
|200||$10,000 – $30,000|
|400||$20,000 – $60,000|
|600||$30,000 – $90,000|
|800||$40,000 – $120,000|
|1,000||$50,000 – $150,000|
|1,500||$75,000 – $225,000|
|2,000||$100,000 – $300,000|
An average attic in the United States is 1,600 to 1,800 square feet.
Some building codes only allow a portion of the attic square footage to be finished.
Attic finishing cost by project
How you intend to use the attic affects the total finishing cost. While all attic finishing projects typically require reinforced flooring, the remaining details and requirements depend on the room size, type, and purpose.
|Room purpose||Average total cost|
|Storage space||$5,000 – $20,000|
|Bedroom / office / bonus room||$20,000 – $45,000|
|Bathroom||$20,000 – $60,000|
|Primary suite (bedroom & full bath)||$50,000 – $100,000+|
Storage space – Finishing the attic for extra or improved storage space is typically the cheapest project type. You'll need solid flooring to walk and hold the weight of whatever you plan to store, but the rest of the details are optional.
Bedroom or office – Converting the attic to a bedroom involves adding stairs, at least one window, constructing a closet, and installing electrical outlets and lighting. Many homeowners choose to install carpet for both comfort and noise reduction. Finally, be sure to factor in the furniture cost to complete the space.
Bathroom – Adding a bathroom in the attic involves many of the same construction details as a bedroom, but also requires running new plumbing lines and installing the bathroom components and fixtures, which add to the project cost.
Attic remodel cost breakdown
The projects involved in an attic remodel depend greatly on the type of space you're creating. An office or playroom may just need flooring, minimal electrical work, drywall, and lighting, while converting the attic to a primary suite with a bedroom and full bathroom needs much more planning, labor, and materials.
Labor and construction costs
Labor typically accounts for 30% to 50% of attic conversion costs, depending on the project scope and the quality of the fixtures and finishes. An attic conversion involves many professionals and a lot of moving parts, from the planning and design phase through to the finishing touches.
A general contractor charges $50 to $150 per hour or 10% to 20% of the total construction cost to oversee the project and manage the other professionals involved.
Planning / design
A structural engineer costs $100 to $220 per hour to determine if your existing attic can support a finished space. Many homes, especially older homes, need the walls, attic floor, and foundation reinforced.
An architect costs $100 to $250 per hour or 5% to 20% of the construction cost to draft plans for the finished attic space.
Construction permits cost $500 to $2,000. Any changes to the home's structure, such as adding walls or dormers, running new plumbing or electrical wiring, or adding ventilation typically require permits and approval before construction begins.
Initial construction labor
Attic cleaning costs $100 to $500 on average to clear out the space before construction.
Interior demolition costs $2 to $8 per square foot and may be needed, depending on the existing attic condition.
Repairing or reinforcing a foundation costs $250 to $800 for minor cracks and $2,000 to $20,000 to fix major issues.
Steel beam installation costs $100 to $400 per foot total to reinforce the walls to support a finished attic.
Cost to add stairs to attic
The average cost to add a staircase to an attic is $1,000 to $5,000 installed. A straight staircase is the cheapest style but has the biggest footprint and may not be practical, depending on your first-floor size and layout. Building a more compact spiral staircase ranges from $1,300 to $18,000.
New stairs are required if the existing attic entrance is a pull-down hatch and you plan to use the finished space for more than just storage. If you already have a walk-up attic, remodeling the existing staircase to bring it up to code costs $500 to $4,000.
Finishing an attic often requires installing not just new flooring, but the structural components beneath it. A subfloor costs $3,500 to $8,600 to install for an average-sized attic. Replacing the attic floor joists, which are typically too weak to support the weight of a finished room, costs $350 to $1,000 per joist.
Once the floor structure is in place, new attic flooring costs $4 to $15 per square foot installed on average, depending on the material. Installing carpet costs $2 to $8 per square foot and helps reduce noise transfer to the rooms below the attic.
Insulation and drywall
The average cost to insulate and drywall an attic is $4,000 to $14,400 total. By itself, attic insulation costs $1.00 to $4.50 per square foot installed, depending on the type.
To convert the attic to a multi-room living space, the average cost to frame a wall is $1,000 to $5,000, or $25 to $64 per linear foot installed for the framing and drywall.
Drywall installation alone costs $1.50 to $3.50 per square foot for materials and labor if no new framing is required.
Once the drywall is hung, professional painting costs $1 to $3 per square foot for the paint and labor.
A new drywall attic ceiling costs $2 to $4 per square foot installed, or $3,200 to $7,200 on average.
Bathroom and plumbing
The average cost to add a bathroom in the attic ranges from $20,000 to $60,000, depending on the size and features. Bathroom additions are costly due to the additional plumbing lines and fixtures required, but finished attics that include a bathroom typically have a higher return on investment.
Most plumbers charge $45 to $150 per hour, or a flat fee for certain jobs.
Installing new plumbing pipes costs $450 to $1,800 per fixture.
A full bath may also need extra ventilation. The cost to install a new bathroom fan is $250 to $950 for labor and the fan itself.
Lighting and electrical
The total cost to add lighting and electricity to the attic depends on the attic size and how you're planning to use the space. Converting the attic to a primary bedroom and bathroom requires much more electrical work than finishing it for extra storage space or a simple bonus room.
When converting a typical attic to usable living space, electrical and lighting cost $1,500 to $3,000 on average. Here's a breakdown of the individual costs:
Running new electrical wiring costs $4 to $9 per square foot for materials and labor.
Light fixture installation costs $70 to $300 per fixture installed, depending on the type.
Installing a ceiling fan costs $250 to $700 for the fan and installation labor.
The hourly rate for electricians ranges from $50 to $130 per hour. Many experienced electricians charge flat rates for specific jobs they've done enough times to know the typical time and materials they require.
Heating and cooling
Depending on your local climate, you may need to budget for heating and cooling when converting the attic to a living space.
A single-zone ductless mini-split AC costs $2,000 to $6,000.
New duct installation costs $270 to $500 per duct run to extend the home's HVAC system to the attic.
A window AC unit costs $150 to $800 for the unit alone. Most window AC units have DIY-friendly installation.
Windows or skylights
The average cost to install an egress window is $3,000 to $7,000, depending on the size and type. Building codes require at least one egress window accessible to the outdoors when converting the attic to a bedroom or other living space.
For extra natural light and an aesthetic upgrade, new skylight installation costs $1,600 to $4,200 for labor and materials.
Cost to raise attic roof
The total cost to raise a roof is $30,000 to $70,000 on average, depending on the size and existing structure. If your attic ceiling is sloped and you're converting the area to habitable space, you may need this extra step. Building codes require at least 50% of the room to have a 7-foot-high ceiling.
If you need to add more space to the attic, an attic dormer addition costs $19,600 to $54,900. A dormer is a smaller roofed structure projecting from a sloped roof, with one or more windows.
Other roofing-related costs may include:
A roof inspection costs $100 to $400.
Roof framing costs $6 to $15 per square foot installed.
Roof vents cost $200 to $700 each with installation.
Roof repair costs $150 to $400 for minor leaks or $1,000 to $3,000+ for major structural repairs.
FAQs about finishing an attic
Can you finish all types of attics?
You can finish some types of attics, but not all types. Some attics present additional challenges and requirements, and some are simply not big enough to comply with all building codes.
An attic framed with roof trusses typically does not have enough space or structural integrity for finishing. To finish the attic in this case, you need to reframe the roof.
A scuttle attic—an attic with a pull-down hatch entrance—cannot be converted to a code-compliant living space without installing a permanent staircase connecting to the first floor, which is not always practical in smaller homes.
Some attics are too small to finish to code, regardless of the roof framing. Building codes require at least 50% of a room with sloped ceilings to have 7-foot ceiling height.
Does finishing an attic increase home value and square footage?
Finishing an attic increases home value when converting the attic to a living space that counts as added square footage, especially when including a bathroom. Basic finishing that simply improves the attic storage space will not increase resale value but may still add perceived value for potential buyers.
How long does it take to finish an attic?
Finishing an attic takes 4 to 8+ weeks, depending on the level of finishing. Converting the attic into a living space with a bedroom and bathroom takes much longer than a simple finishing job to create a playroom or improved storage space.
Do I need a permit to finish my attic?
You may need a permit to finish your attic, depending on the level of finishing. Projects that involve any changes to the home's structure, electrical wiring, plumbing, or ventilation typically require a permit. Contact your local permitting office to determine the requirements for your project.
Getting estimates from attic finishing contractors
Follow these guidelines when selecting an attic remodeling contractor near you:
Look for a contractor or firm specializing in attic finishing and remodeling.
Compare 3 to 5 attic remodel estimates with similar finishing details to compare.
Confirm the company is licensed, bonded, and insured.
Browse reviews on HomeGuide and Google and choose a contractor with a good track record and positive customer feedback.
Ask for local references and photos of similar projects.
Confirm they know and follow the current local building codes and requirements.
Have a detailed contract and warranty in hand before the work begins.
Follow a payment plan for work completed, and only make the final payment when the newly finished space has passed all necessary inspections.
Questions to ask
Ask the following questions to help you choose the best attic remodeling team for your project:
Are you licensed, insured, and bonded?
How long have you been in business in this area?
What experience do you have with attic finishing and renovation?
Will my home need any structural reinforcement to finish the attic the way I'm envisioning?
What does the estimate include?
What additional costs could come up during the project?
How long will the project take?
Can I stay in the home while you're finishing the attic?
What permits do I need for this project, and do you handle them?