A 200-square-foot sunroom addition, including footings and slab-on-grade foundation, post-and-beam construction that’s exposed on the interior, efficient windows, 10 operable skylights, ceiling fan, tile floor, and window shades, costs an average of $74,310, according to Remodeling Magazine’s 2011-12 Cost vs. Value Report. You can expect to get about $34,100 of that investment (45.9%) back at resale, according to the study.

The highest rate of return on a sunroom addition is in the sunny Pacific West. In San Diego, for example, the average cost is $85,177 and the return is $43,184, or 50.7%. The lowest payback is in the mountain regions, where the average cost is $71,883 but the payback is only $26,970 — a 37.5% return.

Wherever you live, the key to maximizing your return is to avoid over-improving. That means building a sunroom addition only if neighboring houses of similar style, size, and value tend to have them.

Of course, return on investment shouldn’t be your only concern when considering a sunroom addition—or any home improvement. Do the project because you want to enjoy it for years to come, and then consider whatever payback you’ll wind up getting when you sell in five or more years as found money.

National average cost, 200-square-foot sunroom addition, with standard appointments:

Job Cost: $74,310
Resale Value: $34,133
Cost Recoup: 45.9%

Regional info

New England

Middle Atlantic

South Atlantic

East South Central

West South Central

East North Central

West North Central

Mountain

Pacific