How Much Does a Home Addition Cost in Knoxville, TN?

It depends on the size, what the room is for, the finish level and how the addition joins the house. The table above shows common sizes, and the estimator gives you a range for your own addition.

The table above shows two 20 by 20 examples, a family room and a primary suite with a full bathroom, both at a mid-range finish. The bathroom is the largest single difference between them, because it brings plumbing, waterproofing and tile.

Building out is usually less per square foot. A second story has to be carried by the house below it, and part of the roof comes off while it goes up, which the estimator accounts for.

Because quotes include different things and make different assumptions about the house. On one addition, rot ran the whole way around the outside of the home and had to be repaired before the new framing could go up. A careful estimate allows for that kind of discovery.

Yes. Every addition estimate includes a line for design and drawings and a line for permits and engineering.

The 12 by 16 bedroom in the table above is a common size. A bedroom with its own bathroom costs noticeably more, because the bathroom brings plumbing, waterproofing and tile.

It depends on what the room is for. A sunroom costs the least per square foot and a kitchen the most, because of the plumbing, gas and ventilation. The estimator works per square foot for the type and finish you choose.

Per square foot it is usually a little less than a single story, because one foundation and one roof serve two floors. Count both floors in the size and choose Out, two stories in the estimator.