A roof deck puts you on top, but not often

It's lonely at the top.

Neal Yaffe has a spectacular roof deck, larger than many apartments, with views of the Boston skyline and tonight's fireworks over the Charles River. Usually, he sees no one else up there. On the Fourth of July, however, these outdoor spaces become coveted grandstands filled with residents and friends, family, and anyone else lucky enough to be invited.

That's a holiday anomaly. The rest of the time, the decks are largely empty.

''My honest opinion of why people don't use these things is they're not accessible," Yaffe said. ''For brownstones, they were an add-on. They have steep ladders or jury-rigged staircases." Kitchens, he said, may be in the basement or two floors down. Many times, especially with setbacks (in some neighborhoods, the deck must be invisible from the front of the building), they are small.

Real estate brokers say roof decks are a major selling point, especially at this time of year. The extra outdoor space, which can soften the hard edges of city living, adds significantly to the value of a home.

The unspoken truth is that people are so busy working or darting to the beach when the weather is nice, that many roof decks end up being places where plants get fried, the grill gathers grit, and the stairs are too tough to navigate -- especially with a tray of margaritas -- at the end of a hot day.

Yaffe said he uses his 1,000-square-foot roof deck over his Washington Street loft, which is for sale, because it has direct access from a staircase inside the condo, and carrying up food or drinks is no trouble.

Not everyone with a deck is so lucky.

''I've seen a lot of places where it's a real steep ladder or circular staircase," said David Crombie. A broker at the South End Realty Group, Crombie goes up to his own roof deck regularly to grill or water plants, but said he never sees his neighbors on theirs. ''So it makes getting up there hard. Even my stairs, they're at an angle, and you have to duck your head at some point. I've seen some real doozies." They include a roof deck where the only access is from a bedroom window to a circular staircase.

Decks offer a glamorized notion of urban life, are the ''sizzle that sells the steak" and will add more value to the property than they cost to construct, according to Steven Cohen, a senior broker at Gibson Domain Domain in the South End. But even he knows that they don't get used that often.

''People derive some psychic kick out of having a roof deck that is out of proportion to its actual utility," Cohen said.

As for his own roof deck, ''I use it in season when it's not raining and I'm able to find the time, which by the time you adjust for all of those factors isn't all that often."

City officials say they have no idea how many roof decks Boston has, but low interest rates and condo conversions, especially in Jamaica Plain and South Boston, have encouraged more people to build them.

Theodore and Susan Touloukian built a deck on top of their Victorian row house in South Boston a few years ago when they revamped the whole home. Both architects, they made sure the deck was properly supported on the old frame, perfectly proportioned and in keeping with the historic nature of the street.

''To build a roof deck can be costly," Theodore Touloukian said. ''It can be a very big structural ordeal."

Still, with their kitchen three floors down, they entertain on the roof about once a year -- yep, the Fourth of July -- when they're at eye-level with the fireworks.

''We don't use it that often," Touloukian admitted. But he'll sometimes climb the stairs to the top at the end of night, when it's quiet and he can contemplate the skyline in peace.

William Findlay of William Findlay & Co. Real Estate on Beacon Hill, does not have a roof deck, but is jealous of his neighbor's.

''I said, 'I love that roof deck.' And he said, 'We won't use it.' "

Findlay, who moved to Beacon Hill from Florida, doesn't understand why. ''In Florida, if you have a roof deck, you'll bake. Here the weather is beautiful all summer long. I think most people just use it on the Fourth of July."

David Mugar can attest to that.

The man responsible for putting on Boston's Independence Day show on the Esplanade is never alone on the roof deck at 100 Beacon St., the 11-story Emerson College dorm he leases only on July Fourth.

''We've used it for about 30 years," he said. ''It overhangs the whole Esplanade. It's probably the best place in all of Boston to watch the fireworks and the concert."

Mugar also has views of hundreds of other roof-deck parties on the Fourth. But as for deck use throughout the rest of the summer, his Back Bay friends aren't around to bother, because they're at their vacation homes.

John Delano can relate to that.

He would have great views of the fireworks tonight from the roof deck of his new home behind the State House, but he'll be joining his family at their vacation spot in New Hampshire. Still, he believes he may use this roof deck more often than his last one, atop a Myrtle Street town house, because he can get access to the outdoor space from the home office where he runs an insurance business and spends much of his time.

''The realtors all tell you you have to have a roof deck for resale," Delano said. ''They're beautiful to have, but I don't know how much anybody uses them."

Tina Cassidy can be reached at cassidy@globe.com.