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Cost of a House Addition

You’ve saved up your hard earned money. You’ve got a general idea of what you’re looking for. And now you just need a ballpark price. So here are the big questions - how much will a new addition cost? What is the average cost of a new addition in my area?

New addition on green house

House Addition Costs

The average national cost of adding a room or building an addition is $43,547, with most homeowners spending between $20,900 and $66,942. This data is based on actual project costs as reported by members.

So obviously that is a big range, and whether you fall closer to $20,000 or $70,000 depends on a few factors. Let’s dig in shall we?

It’s an investment in your current home and an upgrade to your lifestyle. If done properly, it can make your current house feel like your dream house - and that’s the goal.

Consider what type of addition you want

The size and scope of the project will obviously help determine the final price. Here are a few addition sizes to consider:

Extra room or bedroom: This is a flexible space that can be used for almost anything. An office for a work from homer, or a bedroom for a growing family, or a gym for the fitness lovers. Considerations are whether this space will conform to your current home or if you need to build out or build up to create the space. You may need to hire an architect or design/build firm to complete the job.

Sunroom or Three-Season Porch: Another addition project on the lower end of the scale is a sunroom or three-season porch. The cost of this project depends on the amount of space it adds, the location of the sunroom, extras such as electrical wiring and whether the room is heated (four-season room) or not heated (three-season room).

Detached Addition: Detached additions can range in style and price, with prefabricated, simple rooms running around $15,000 without electricity or heat, or full guest houses that share similar costs as a detached garage addition, which run around $24,658 on average.

Cost Factors

When you’re planning your budget for this project, you need to consider many different factors, including the square footage and the size of the addition. The larger you go, the more expensive the project will be. Other important factors include necessary services, including:

Architectural services make sure that the design of the new addition looks good with the style of the home. This typically accounts for 15% of the total project budget.

Excavation, demolition and site-preparation costs vary depending on the amount of work that needs to go into the prepping. For example, removing a wall costs $300–$500, while excavation costs around $2,559 on average.

Finishing the interior by drywalling the ceiling and walls costs an average of $9.80 for each sheet of drywall.

Other Considerations:

Resale Value: Even if you have no plans to sell anytime soon, consider the resale value of your project. Because they're among the most expensive home projects, additions sometimes return less on your investment than remodels. If you're significantly adding to the square footage of your home or adding important types of rooms, such as bedrooms and bathrooms, your investment may pay off considerably.

According to HomeAdvisor, adding on to your home is among the priciest projects that you can undertake as a homeowner. Experts suggest that you can expect to see a return on your investment of:

  • 49% for sunrooms
  • 53% for bathrooms
  • 63% for master suite additions
  • 65% for a two story addition with an upstairs master suite and a downstairs living area

Local Zoning Laws: Always check with your local government to research zoning restrictions. In some areas, you may not be able to build within a certain number of feet of the front, sides or rear of the property lines. Other areas have rules about how much space on your property can be covered with buildings, how close you can get to protected spaces such as wetlands or how high you can build up.

Ready for a new addition? Don't renovate alone. Contact us today to speak with a HireHaven project expert and we'll get you multiple quotes for your project, no matter how large or complicated! There's too much at stake to make a mistake.