How Much Does it Cost to Build a Secret Room?

Typical Range:

$800 - $50,000

Find out how much your project will cost.

Cost data is based on research by HomeAdvisor.

Updated April 16, 2024

Written by HomeAdvisor.

Highlights

  • Building a secret room involves complex tasks like electrical and plumbing work, making professional help essential.

  • The cost to build a secret room ranges from $800 for simple concealment to over $50,000 for high-end safe rooms.

  • Project cost is influenced by type of room, type of concealment, required installations like plumbing or electrics, and professional construction.

  • Popular materials for building a secret room include high-density fiberboard, custom and stock concealments, locks, and electrics.

  • Building a secret room provides concealed storage space, a leisure area, safety, or a hidden wine cellar.

Highlights were summarized from this existing cost guide text using automation technology and were thoroughly reviewed for accuracy by HomeAdvisor Editor Ryan Noonan.

The cost to build a secret room is, on average, $25,400. It can cost as little as $800 or as much as $50,000 depending on the size of the room, the scope of the project, the purpose of the room, and the type of concealment you choose. Converting an existing closet with a simple bookcase concealment into a secret storage space falls at the low end of this range while having a safe room custom-built with an impenetrable vault door concealment will push your costs to the upper end of this range.

Average Cost to Build a Secret Room

Low Cost$800
Average Cost$25,400
High Cost$50,000

Cost to Build a Secret Room by Project Scope

There are numerous options for building concealed rooms in a residential property. The project scope, or the way the room is to be built, has a direct impact on cost.

Using a Closet or Existing Room

The easiest way to build a secret room in your home is to frame in and conceal the entrance to an existing closet or room. If you don't have extra closet space, but you do have a spare bedroom or office, you could apply the same principles and conceal the entrance, quickly and affordably creating a hidden room. If done well, visitors would never know the room was there. This kind of conversion costs as little as $800 for a single-wide bookshelf concealed door. If you can do the job yourself, that's all you'll pay. However, if you want professional installation, you'll need to hire a handyperson. Hiring a handyperson costs between $55 and $75 per hour. Assuming the job remains relatively simple, it should take less than a day to conceal the entrance to the room or closet.

Partitioning Off a Larger Room

If you have enough space, you can partition off a larger room to create a secret room. An open plan basement is a great spot for this type of concealment, particularly if you're already planning to remodel your basement. Adding a wall with framing for a door costs $20 to $30 per square foot for framing and drywalling, plus another $120-$200 for the doorway, including labor and materials. On top of that, you'll also need to pay for the concealed door itself which starts at $800 for a traditional bookcase or, for something more fancy like a swing-up fireplace, you could pay up to $10,000. And then there's the installation of the concealment which costs another $55 to $75 per hour.

Building an Addition

If you don't have enough spare space in your home to create the secret room you need, you'll have to build a new room to accommodate the concealment. This is a reasonably common choice among those who want to build a safe room or panic room in their property and need a good-sized, well-fortified room to do so. For a basic 10 by 12-foot room, exact to pay between $9,600 and $24,000 for the room itself. On top of that, you'll need to purchase the concealment that costs anywhere from $800 to $12,000, plus installation at a further $55 to $75 per hour. And this doesn't account for the electrics, plumbing, emergency supplies, ventilation or other elements necessary for a safe room, which we discuss below.

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Cost to Build a Secret Room by Type of Room

If you want to build a simple concealed storage room to keep your bargain multi-buys or endless baskets of craft supplies out of sight, all you need is a small, shelved space behind a basic concealment. If, however, you need something more elaborate that can sustain you and your family for hours or days in the event of a crisis, expect to pay a substantial sum.

Storage Space

Building a hidden room for storage is a relatively simple affair and doesn't require new electrics, plumbing, or ventilation. If you need a little accent lighting, you can always use battery-operated LED light strips. For the storage itself, the materials for shelving or a tall bookcase start at less than $100 if you can install them yourself, otherwise a handyperson will charge an additional $55 to $75 per hour for installation. Then factor in a simple concealed entryway starting at $800, plus labor.

Leisure Room

A leisure room, such as a home theater, hidden away adds a great sense of whimsy to your home and conjures up those childlike fantasies of secret passageways and hidden rooms. If you already have a room used for fun, whether that's family movie nights, a games room, or a craft space, then you can simply remove the old door and sill, frame in the space, and add the concealed door of your choice. This would be the least expensive option.

Alternatively, you could add the concealment to your basement entryway or partition off a section of your basement to create the hidden leisure space. As well as the concealment and the cost of adding a wall partition, you'll also need to account for additional wiring and lighting, and the cost of any equipment, such as a home theater setup and seating. Creating a home theater can cost anywhere between $2,000 and $30,000 all-in.

Safe Room

A safe room can be as safe as you want. They can be as simple as a walk-in closet with high-density fiberboard-reinforced walls and door with a doorway concealment that can withstand brute force attacks for 30 minutes to an hour, giving police time to arrive and help if intruders break in. Or they can be self-sustaining locking vaults with bullet-proof doors and walls that will keep you and your family safe for days at a time in the event of a natural disaster.

There is no upper limit to the amount you can spend on a safe room. A small safe space with fiberboard reinforcement can cost as little as $5,000, all-in including the concealment. At the other end of the scale, you can pay well in excess of $50,000 for a bullet-proof, high-end safe room with ventilation, plumbing, electrics, and more.

Wine Cellar

A wine cellar costs around $40,000, depending on the size and any special requirements. The main consideration for building a wine cellar as a secret room is refrigeration and temperature control. Based on a 25 to 150 square foot space, adding refrigeration to a room costs on average $5,500, while adding temperature control averages around $1,800.

Building a Secret Room Cost Factors

Aside from the room and its purpose, there are other cost factors you need to take into consideration, too. These range from the type of doorway concealment you want to whether you need to install electrics, plumbing, and ventilation.

Type of Concealment

The type of concealment has a big impact on the price of your hidden room. Let's take a look at the starting prices for some popular doorway concealments.

Concealment TypeStarting Price
Single bookcase$850
Bi-fold bookcase door$1,500
French door bookcase$1,800
Wall mirror$2,500
Pool cue rack$7,500
Wainscotting$10,000
Stone facade$10,000
Fireplace$12,000
Double slider bookcase$15,000

Type of Lock

There are endless creative lock designs for secret rooms, and prices vary a great deal. A simple mechanical key lock starts from $149, while high-end biometric or facial recognition locks can cost over $1,000, plus installation.

Plumbing

If you're getting fancy with your secret room and plan to stay there for hours or days in the event of an emergency scenario, you'll need a bathroom. Adding a bathroom to an existing space costs between $5,000 and $35,000, depending on the size, number of fixtures, and complexity of the job.

Electrical

If you've had a new addition built for your secret room or you're partitioning or remodeling a basement, you'll most likely need to hire an electrician to run power to the room, install light fixtures, and add outlets. You may also want to consider adding a backup generator so you've always got power. A portable backup generator costs between $300 and $1,200.

Ventilation

Unless the space already has adequate ventilation, you'll need to add some. Ductwork costs $10 to $20 per linear foot, including parts and labor.

Custom vs. Stock Materials

You can still accomplish the “big reveal” of a hidden swivel door without worrying about building something custom. Brands like Murphy Door sell hidden doors in a variety of styles, shapes, and colors starting at $1,000. Pricing is for the door only and you may need to pay extra on top for the labor to install if not installing it yourself.

DIY vs. Hiring a Pro Contractor

Full secret room builds, basement remodels, and partitions are best left to professional contractors. However, if you have the right skills, you can save on labor by doing some jobs yourself. For instance, if you're an experienced DIYer, you can install the concealed doorway in an already framed space yourself. For example, if you're concealing a spare bedroom or a closet, then yes, if you have the right skills, you can install the concealment yourself.

For larger projects, such as building a new secret room, hire a construction manager to take care of the entire project for you. For smaller jobs, like partitioning a larger room and installing new electrics and plumbing, you'll still need to hire the appropriate professionals, as all of these tasks likely require permits and inspections as well as very specific skill sets.

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FAQs

Are hidden rooms legal?

Yes, hidden rooms are legal, as long as they meet all local building regulations. If you sell your house, most states require homeowners to disclose full houseplans, which would include any hidden rooms.

What should be in a safe room?

If your secret room is a safe room, it should contain a means of communication aside from a cell phone, such as a shortwave radio. You should also have plenty of drinking water, a portable generator, emergency food supplies, blankets, pillows, flashlights, batteries and a first aid kit.

Does a secret room add value to your home?

Any time you update your home’s square footage, you increase its value, but a secret room is a niche feature that doesn't rank high on every buyer’s list of must-haves. Investing your money in remodeling more common living areas like bedrooms, bathrooms, or kitchens will have a higher ROI than adding a secret room. Many secret rooms can act as entertainment spaces (think a game room or wine cellar) or quiet spaces (a library or study), so when building your secret room you may want to consider its versatility for when you’re ready to sell.