The average cost per square foot to build an extension in your home

Planning and building a new home expansion is a great project as it is a great way to invest money and make a profit in the future when the market value of houses increases. However, the original cost per square foot (929.03 cm²) for an expansion can be high and requires tight budgets.

Building attachments

Most extensions require a completely new construction, from foundational elements to new materials for roofs and canals. Basically, this is almost as much as building a new home, so homeowners often use new home construction costs to figure out how much they have to spend. In general, in 2011 it cost between US $ 100 and US $ 300 per square foot (929.03 cm²) to build a new house, like most extensions, not including any furniture or complicated extension such as canteens, but electricity, Plumbing and other necessities.


For some homeowners, the line between an extension and a remodel is very inaccurate, as it may seem easier to remodel a home and increase its size at the same time. These remodeling costs closely resemble the prices of new home construction, in 2011 ranged from US $ 115 to US $ 250 per square foot (929.03 cm²) to remodel a single room with an extension. A two-floor extension tends to start at the upper limit of US $ 175, while a multiple-room extension falls in the range of US $ 150 to US $ 325.


There are important variance factors that affect the price of a home’s expansion. One is location, since labor and materials always vary in price from one place to another; But the main factor is the quality of the materials that the owners choose, because the wood costs more than the carpet and the price of the stone is higher than the vinyl, and thus prices can increase quickly to US $ 300 and more with The choice of high-end materials. For this reason, it can be difficult to create averages without having an idea of ​​what the owner wants.

Extensions in existing spaces

Building an additional space may not seem like an extension, but in many cases allows owners to change the attic or basement through a new meeting room. In this case, prices are much lower because the basic structure is already built. Basements can cost about $ 40 per square foot (929.03 square feet), while the attic can cost less, equal or more, depending on the electrical system and existing plumbing.