Home additions are expensive, but can add value to your house. Don't expect to get a dollar-for-dollar payback on every one, however. A lot will depend on the size and condition of your house, the home's location, the kind of addition you make, whether you intend to put your house on the market right away or some time in the future, as well as the general housing and economic conditions.
Study your house to determine where it will be easiest and cost effective to add an addition. Consider such things as the cost of a foundation and the cost to extend the roof, in addition to exterior siding and interior finishing. Determine the square footage of what you would like to add; house additions can range from under $100 to $250 per square foot. Room additions, decks, kitchens and bathrooms can add a lot in terms of value to your home.
Figure $1.30 to $2 a square foot for any new roofing, up to about $3,000 for electrical work, up to about $4,000 to install new heating and cooling if you have to replace a unit and somewhat less to just extend ductwork to new areas. Estimating costs of new foundations will vary with the type of construction, soil conditions and excavation required.
Use an online calculation program to determine approximate costs for various home additions. Enter your state or area, put in the specifics of your addition and let the program calculate approximate costs. Ask contractors for detailed estimates once you have an idea how much your addition may cost and its potential to add value. "Remodeling" magazine has a Cost vs. Value website to help you determine the most beneficial additions.
Add a shed roof dormer to create an attic bedroom for one of the most beneficial additions. Figure dormer additions at $80 to $120 a square foot, usually a total of between $5,000 and $20,000, depending on the size and roof style. "Remodeling" magazine pegs an attic bedroom addition at about $49,000, but determines it will add 80 percent of that in value.
Expand an existing wood deck or build a new one for a minimum of $10,000 and up to more than $35,000, but expect 75 or 80 percent of that cost in added value, depending on your location. Match the deck to the style of your house and neighborhood; wood decks typically add more value than other types. Typically, a deck adds more value in warmer climate than cold ones.
Enclose a concrete porch or patio to make a room. Create a family room for $80,000 or more, a sunroom for slightly less, but expect to gain only 50 to 60 percent of the cost in added value. Add or expand a master suite for $100,000 or more and you will enjoy more comfortable living, but will increase the home value by only about half the cost.
Explore options for kitchens and bathrooms. Determine if you can expand and improve those areas without major foundation, wall or roof construction. Add 60 to 80 percent of the cost of kitchen and bathroom additions in value, but realize that prices can range from about $15,000 to more than $100,000, depending on the size, type of flooring and other variables.
Bob Haring has been a news writer and editor for more than 50 years, mostly with the Associated Press and then as executive editor of the Tulsa, Okla. "World." Since retiring he has written freelance stories and a weekly computer security column. Haring holds a Bachelor of Journalism from the University of Missouri.