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As a leading real estate data company, Kukun has detailed data on virtually every home in America. We use this data about your home’s size, bedrooms, bathrooms, location, value, and more, to create a highly accurate cost estimate of the renovations you want to do.

Plus, we show you the ROI on your renovation and options for saving money or making more luxurious selections.

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Room addition cost calculator

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Room addition cost calculator

A house that may look perfect at the time of buying it may seem inadequate in a few years. With a growing family, your housing needs may change. The kids will need an extra bedroom, your work-from-home setup may require you to build a separate home office, or you may need a mother-in-law suite for an elderly parent. Very soon, you'll be looking for a home improvement project to cater to your new spatial requirements. Our room addition cost calculator will help you in this journey to add more living space to your home.

It will help you calculate your total expenditure in building an addition so that you can make an informed decision - every step of the way.

Keep in mind that although building a home addition may be an expensive project, it can be highly rewarding. An inexpensive way to add a room to your home is to finish an existing space such as an attic, a basement, or a garage. That way, you'll not have to buy a larger house for some extra space. And, you'll save money by utilizing an existing area. If you're looking at the cheapest way to add square feet, you may opt for a bump-out addition. Here, you can create an extra space that's smaller than a full-fledged room addition. A bump-out can be as small as two feet or as long as 10 to 12 feet. An increase in square footage, however small, can increase your property value significantly.

The average room addition cost runs from about $120 to $400 per square foot. The total cost of a home addition may be anywhere between $30,800 and $84,000 depending on the size and type of addition it is, the quality and finish of the materials used, the complexity of the architectural design, permits or inspections, and your zip code. For instance, adding a 12x12 bedroom will cost you about $22,300 while adding a 20x20 family room may cost you approximately $63,000 on average. You can expect to pay around $19,000 for a basic bathroom addition.

As mentioned earlier, your location plays an important role in the total room addition cost. For example, the average cost per square foot can be as high as $330 in areas such as San Francisco.

Your home addition's size, type, and location are the primary cost drivers. Apart from these, there are factors that significantly increase the final price. These include:

  • Style and complexity of the architectural design
  • Type of building material, finish level, and overall quality
  • Arranging for home remodeling permits and home inspections
  • Factoring in unexpected plumbing, HVAC, or electric issues

Room addition costs depend highly on the type of work involved. Here are some of the most common room additions that homeowners typically invest in:

Room additions Average Cost (Approximate)
Master suite $59,400 to $96,500
Bedroom $16,300 to $34,900
Living room/Family room $34,400 to $83,200
Mother-in-law suite $44,000 to $100,000
Bathroom $14,000 to $47,000
Mudroom $7,880 to $12,200
Sunroom $14,100 to $30,000

Real knowledge will always give you an edge over conjectures. An estimate will help you organize your home improvement project better - effectively managing your room addition budget and funds. Additionally, it will help you get quality work at a fair price. With a good home addition cost calculator, you can create a realistic budget. It's one of the best ways to ensure that you don't stumble across any unwelcome surprises during the execution of your home addition project.

A home addition cost estimator will help you plan your project in detail. Once it gives you a budget estimate, you can regulate your funds better and steer clear of any money-pit projects that may dig deep into your savings. The last thing you'd want is to begin the construction project and abandon it halfway because you ran out of money. What's more, armed with a cost estimate for your project, you can get started on the work right away. You can analyze your finance options or hire a professional after exploring each contractor's profile, their online reviews, and previous permits.

If you're planning to add more space to your house, you'll need to figure out the approximate home addition cost. A reliable online home addition calculator like ours will give you a ballpark estimate. The free tool arrives at it by factoring in the square footage, the building material cost, labor cost, the scope of the renovation, and the requisite permits.

Using Kukun's room addition cost calculator is easy. Just follow these steps and get your home addition cost estimate in minutes!

  • 1. Select room addition cost calculator on the home renovation cost estimator page
  • 2. Choose the type(s) of room addition you plan to make
  • 3. Enter the size of the new space (Check the box if you're fine with including space from adjoining rooms)
  • 4. Provide your exact address with house details and zip code (Your location helps us give you a better cost estimate as we can keep a track of the labor and material prices, permit history, and similar renovations in your neighborhood.)
  • 5. Enter your home size
  • 6. Mention your approximate home value

Get your personalized project cost estimate in seconds! What's more, you can customize the price estimate according to different finish levels - Value, Quality, or Luxury. And, whether you're planning to hire a general contractor or not. Save the plan and begin your home renovation on a wonderful note.

When planning a home addition, it's crucial that you understand how it will look attached to the main home. It should be an organic extension of the house, not stand out like an ill-planned afterthought.

You'll therefore require professional architectural planning and design before going ahead with the home remodel.

Whether it's a sunroom, an in-law suite, siding, or roofing, the materials and style should match and complement your original home in some way or another. Keep in mind that prospective homebuyers prefer to see an expanded footprint of a property. A cohesive look will add to your home's curb appeal in the present and sale price in the future.

The cost to hire a general contractor can be anywhere between $50 to $300 per square foot - depending on the work and requirements. Keep in mind that you'll need to factor in a markup of 10% to 30%.

An architect can help the contractor with architectural drawings and building plans that meet local building codes. And, your remodel vision. The pro is especially required If you want a second or third-story addition.

The cost of hiring an architect depends on the project scope and the payment method. They could charge a percentage of the total construction cost, a flat rate, or an hourly rate. The average cost comes to about $880 to $2,500.

A room addition, whether you build up or out, costs tens of thousands of dollars. Before you begin the expensive work, you should consider your return on investment (ROI).

In general, a room addition offers an ROI of about 40% to 50% - depending on the type of home addition it is. And, on whether it increases the functionality and convenience of your living.

  • A room addition with a bathroom offers an ROI of about 60%.
  • A multi-room addition with a bathroom and a separate entrance offers an ROI of about 85% to 95%.
  • High-end, luxury remodels offer a lower ROI of just 20% to 25%.

A room addition is a great option for homeowners who want to create more living space, without buying a new home. After all, it's cheaper to improve a house that's undersized or outdated than to move to a new one.

If you plan your room addition well, you can successfully build onto the existing floor plan, have a story addition, or convert an unused space.

The two most important steps to a room addition are planning and execution. Here are some tips to make the remodeling process easy, quick, and seamless:

  • Plan the layout for the new space. You may need to hire an architect to help you visualize how the addition will look eventually. Keep in mind that it should be an organic part of your home - not something that sticks out like a sore thumb.
  • Make sure your room addition adds to the functionality, convenience, and value of your home.
  • Set a realistic room addition budget - if you follow the Kukun plan closely, you won't have the typical over-budget surprise that you hear about.
  • Make the effort to get a building permit, it costs more and takes a little more time, but your home value will go up far more with permitted, inspected and approved work. Check your local building code for permit requirements and zoning laws.
  • If you're building up with a story addition, make sure your house structure supports the new addition.
  • Work only with experienced, insured, and licensed contractors and subcontractors. Nothing adds more value to your home than a professional, flawless finish.
  • Make sure the plumbing and electrical work are in place in the new space.
  • Get a warranty or guarantee and a written contract from your remodeling contractor. Make sure it has all the details of the project schedule, deadlines for milestones, and complete payment information.
  • Maintain a project completion timeline and stick to it. Keep in mind that spring and summer are especially busy seasons for home renovations. Avoid them if you can.
  • Be prepared for the construction noises as well as disruptions to your routine. Keep your neighbors in the loop too.

These steps will help you avoid unexpected hassles - ensuring a smooth room addition project.

We answer every question you may have. This feature equips you with everything you need to know about home renovations

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