So four years ago, Pitkin County, which has authority outside the city, got mildly tough and set a limit on house size - 15,000 square feet and no more than 4,750 additional square feet in basement and garage. Today the countryside is erupting with whole developments of houses built right to the limit.
Such "monster homes' - a new slang sums up the architecture - have become a fad in the West's resort communities, where for decades the wealthy have congregated or flitted through, but not so obviously.
With their sheer bulk and often an opulence that is even harder to ignore, the new monster homes dominate landscape and neighborhoods, increasing surrounding property values and making it harder for middle-class locals to buy.
Some communities are taking extreme measures, saying that when it comes to square feet, enough is enough.
Over the pass from Aspen, in the resort town of Crested Butte, monster homes have been rejected. The Crested Butte Town Council voted last summer to limit single-family homes to 2,500 square feet in the historical core district and 2,800 square feet in the rest of the town.
Crested Butte Planning Director John Hess says that several massive homes imposed upon the former mining town helped focus attention on the need to set limits. "People are worried about the community losing historic scale," says Hess.
Gunnison County, which has authority for the countryside outside Crested Butte, is considering floor-area limits. "It's one of our primary points of review," says county planner Steve Westbay.
"We have our fair share of homes in the range of 10,000 to 12,000 square feet," says Westbay. "We haven't seen any with 30,000 to 40,000 square feet yet, but I think it's probably a matter of time."
Some resort towns have special leverage on monster homes that are occupied only part of the year, as seasonal or vacation getaways.
In and around Park City, Utah, thanks to a provision in state law, second homes have been put to work for the locals.
The Utah constitution offers a "homestead exemption" on property taxes for primary residences. Second homes are taxed nearly 50 percent more than primary residences. As Park City Public Affairs Director Myles Rademan says, "If you want to play you have to pay."
Despite the property-tax load, the Park City Board of Realtors reports that sales of new second homes surpassed last year's record pace. Seventy-one percent of the people who own property in Park City live elsewhere.
"Most new subdivisions average 4,000 square feet (per house) and going up," says Rademan. "No one builds less than 4,000 square feet anymore, and you see homes 6,000 to 10,000 square feet."
Such homes are built as "private family lodges," where generations of a family can come together, Rademan says.
Rademan says local residents get irked by the monumental homes. "It tweaks the local consciousness that the middle class is dissolving."
In and around the resort town of Jackson, Wyo., there has been increasing concern about new homes as large as 23,000 square feet, and three months ago Teton County adopted a comprehensive plan that would limit single-family homes to 8,000 square feet of "habitable space." The Jackson Town Council is considering a similar limit.
People in the Jackson community felt that larger homes "were consuming far more resources than single-family homes should," says Bill Collins, Teton County planning director. The larger homes were seen as "changing the community's character," Collins says, and there was a "bulk and scale, visual-impact issue."
Some towns and cities, such as Aspen, regulate house size on a sliding scale that depends on the size of the lot being built upon. Homes inside Aspen city limits top out at 6,000 square feet.
Yet this summer in Aspen, controversy flared as new houses were built out of scale and sync with neighborhoods of smaller Victorians and traditional mining cottages that are in no way cheap themselves. The Aspen City Council responded with a new ordinance that required a design review for any house proposed to have 80 percent of the allowable maximum floor area for each lot.
"We've got to defang the monster," Aspen Mayor John Bennett told The Aspen Times. "These homes sit like great, silent tombstones."
When real estate agents griped that giving up even a couple hundred square feet would cost them hundreds of thousands of dollars in sales commissions, two weeks ago the City Council relaxed the new requirements somewhat.
"We just want people to think about where and what they're developing," says Leslie Lamont, deputy director of planning for Aspen. "This isn't Boca Raton, Florida."
* Ray Ring, Alexei Rubenstein