How Much Do Room Additions Cost?

Although it is hard to generalize about how much various room additions cost, if you are a homeowner and new to the topic, it might be worth your while to develop a ballpark understanding. It is also important to bear in mind that not all room additions hold their value equally (more on that below).

Here is an overview of average room addition costs as listed in the 2013 Cost v. Value Report published by Remodeling Magazine. Dollar-figure amounts are specific to the South Atlantic region, which includes Delaware, Maryland, West Virginia, Virginia, North Carolina, South Carolina, Georgia, and Florida.

  • Bathroom additions – $34,852
  • Wood decks – $8,550
  • Composite decks – $14,389
  • Family room additions – $73,082
  • Garage additions – $46,123
  • Master suite additions – $94,589
  • Sunrooms – $68,181
  • Second story additions – $144,436

In terms of value, which is defined as return on investment, rooms additions vary considerably. According to the Cost v. Value Report, wood decks have the best cost recoupment value of all the additions listed here at 83.4 percent. For example, if you spend $8,000 to build a wood deck, you will earn approximately 83 percent of that money ($6,640) back later when you sell your home. Of the other additions listed here, those with the highest return on investment include composite decks, garage additions, family room additions, and second-story additions.