Done right, a family room addition can totally transform your house. Your kitchen will feel larger, the whole first floor will become spacious and modern, and you’ll wind up with a multipurpose space that’s a comfortable spot for anything from watching movies to holding family Wii matches to hosting large holiday gatherings.


Creating a successful family room add-on requires making some tough choices about what features are right for your space. As you work with your designer, architect, or contractor to plan your project, here are the most important features to consider:


The basics


A 16-by-25 foot family room addition constructed over a crawlspace foundation, with vinyl siding, hardwood floors, recessed ceiling lights, and 180 square feet of glass, has a median cost of $83,118, according to Remodeling Magazine’s latest Cost vs. Value Report. You can expect to recoup about $50,000 — 60% of your investment — when you sell the house.


Location, location, location


Though a family room can technically be built just about anywhere, the best spot is right next to the kitchen, says Phil Kolby, a contractor in Charlotte, N.C. It should open onto the kitchen without a wall between the spaces. That can make an undersized kitchen feel larger, and it creates one large multi-use space that accommodates cooking, eating, entertaining, and just hanging out.


Windows on the world


Because kitchens tend to be at the back of houses, family room additions are, too. So plan for plenty of big windows that let the views, the sunshine, and—when the weather is right—fresh air inside. You’ll pay anywhere from $500 to $1,200 per large window, depending on its style, material, and manufacturer. As with all of the details in your new room, look to match the existing house as much as possible.


The back door


Many family room additions include a door to the back yard. Obviously, you’ll need to plan its location based on any existing deck, patio, or porch. But there’s a good bet that the new family room is going right where that outdoor space used to be. So, either include a new outdoor entertaining area as part of your project (from $5,000 for a deck or patio to $20,000 for a screened porch) or come up with a rough plan for a future one so you can put the door in the right place.


Also, consider an atrium style door, which is a double French door with another, non-operational door panel on each side. It’ll cost $2,000 to $4,500, depending on the manufacturer.


Plan ahead for home theater


There was a time when big entertainment centers dominated family rooms, but now everyone wants a minimalist look. A large flat screen television gets hung on the wall, the components get stashed in a cabinet or closet, and the speakers get installed in the ceiling.


By planning this out ahead of time, you can put all of the wiring into the open walls and ceilings, when that’s an easy and low-cost job. Figure just $300 to get everything wired in before the wallboard goes up. The television and other equipment, of course, can range from $2,000 to $30,000, depending on what you choose and whether you buy it from a big box store or a specialty shop.


Consider a fireplace


In cold climates, a fireplace is a wonderful family room feature. It can be a formal design with a traditional stone surround and a wood mantel—or a simple brick firebox placed on the wall without a lot of ornamentation, says Matt Davitt, a design/build contractor in West Kingston, R.I.


Most of his clients prefer a gas-burning unit: It can be lit and extinguished with the click of a remote control and allows you to skip a full-fledged chimney because it can be vented directly through the wall. That runs $2,000 to $8,000. For a wood-burning fireplace, you’ll need to add a chimney to the project, bringing the total cost to $8,000 to $12,000.


Dress up the ceiling


A few simple ceiling upgrades can add visual appeal to the room. For example, depending on the design of the roof above, you may be able to install a cathedral ceiling—possibly with skylights, for around $5,500.


Or you can bring a casual, cottage-y feel to the space by covering the ceiling with bead-board, for $1,200 to $1,500.


Exposed beams and rafters also create a relaxed look—but eliminate the opportunity to insulate the ceiling, so they’re not appropriate for year-round houses in most climates.


Wet bar


If you’ll be using the family room for entertaining, you might also think about adding a wet bar. This is a countertop and sink, plus storage for glassware, dishes, platters and other party tools.


You can even install a second dishwasher in the wet bar so you don’t have to truck the dirties into the kitchen for washing—and so you can double the speed of post party cleanup by running two machines at once. Expect to pay around $3,000 to $5,000 for a wet bar—and then let the parties begin.