The District's skyrocketing real estate prices have fueled an increase in illegal construction as property owners across the city are building and renovating homes without obtaining the required permits, according to D.C. officials and a review of city records.

Using tips largely supplied by neighbors turning in neighbors, the D.C. Department of Consumer and Regulatory Affairs issued more than 1,400 stop-work orders for illegal construction during a recent 17-month period and has fined the violators nearly $1 million.

By comparison, Montgomery and Fairfax counties each issue fewer than 50 stop-work orders a year, officials said. Prince George's County officials said they issued about 135 such orders last year.

Many of the District's violators are homeowners building additions because they cannot afford to move to more spacious homes, while others are investors renovating properties in the hopes of selling them at a substantial profit, city officials and community activists say. The number of stop-work orders also reflects an aggressive crackdown by the D.C. regulatory agency, which once had a reputation for slipshod enforcement of building codes.

Patrick Canavan, the agency's new director, noted that the permit process is critical because it triggers inspections that show whether buildings meet safety standards and because improvements filed on the permits help determine property tax assessments.

Canavan said the city will not tolerate property owners and contractors who flagrantly violate building codes. "When we catch you . . . we're going to nail you," he said.

A review of 300 stop-work orders citywide showed such violations as hanging drywall before the city has inspected electrical and plumbing work, and renovating kitchens and bathrooms without building permits. Officials said other cases involve property owners who obtain permits for small projects such as decks but instead build additions, and contractors constructing houses without proper approvals.

The inspectors rely mostly on complaints from residents about neighbors violating building or zoning laws. For most construction projects, permits must be posted at the site, and inspectors place the bright red stop-work orders on properties where approvals have not been obtained.

Deanwood, a working-class neighborhood in the far eastern corner of the city, has become a hotbed for property owners and builders working without permits. D.C. Council member Vincent C. Gray (D-Ward 7), who represents Deanwood, said he is concerned that cheap properties east of the Anacostia River, including some that are vacant or abandoned, foster illegal construction because the profit margin is greater, even when the work is shoddy.

John Frye, a community activist, frequently cruises Deanwood, looking for illegal construction. "They're disrespecting the law," Frye said of some builders. "They're working with the stop-work orders posted where you can see them."

Frye calls the city from his cell phone when he runs across oddities, such as the giant hole he spotted in the 1000 block of 45th Street NE. Someone had demolished a house, leaving a two-story-high deck on stilts. Delores Jones, who lives a couple of doors from the property, said a backhoe had been "digging evenings and nights."

City building records show inspectors issued four stop-work orders to the property owner, Duane McKinney, and fined him $3,000. McKinney, head of the McKinney Construction Co., declined to discuss the citations.

Inspectors can issue fines ranging from $500 to $4,000 for repeated violations.

Frye and other residents also alerted city officials to the practices of Dixon A. Oladele, a builder arrested in January on 296 charges of erecting a building without a permit. Oladele had received stop-work orders at six properties over four years and had paid the city more than $200,000 in fines in connection with 39 citations.

Oladele acknowledged in a recent interview that he started several projects before his building permit applications were approved. "One of my problems is impatience," he said.

Permits generally are needed for projects ranging from putting up a fence or backyard shed to expanding a room. Property owners who are unsure whether they need a permit should call the regulatory agency or visit its Web site, dcra.dc.gov, before beginning a project, agency officials said.

Officials said permits can be obtained in a day for such projects as decks and in a month for major renovations. But some residents and contractors complain of lengthy waits for officials to review plans, issue permits and respond to requests for inspections. Some people hire "expeditors" who can help speed the process.

Edmund L. Peters, a permit expeditor, said it can take up to six months for homeowners and builders to get a building permit for a new house.

"The reason why people don't get permits is because the DCRA makes it very difficult for people to get them," Peters said.

Frank Economides, a Northwest homeowner charged with failing to obtain valid permits, contends that the regulatory agency mishandled his case.

Economides and his wife had lived in the affluent Wesley Heights neighborhood in Northwest for 12 years when they decided to expand their 5,000-square-foot home by adding guest quarters, a family room, an office and a wine cellar. He obtained a permit for the addition in 2002. But when the work began, he said, a bulldozer slid into his house on Dexter Terrace NW and damaged it beyond repair. He demolished the structure and began building a 9,000-square-foot home.

City records show Economides received two building permits after he demolished his house. But city officials said those permits were issued in error because Economides did not first obtain a valid demolition permit. Economides, a city developer for 20 years, has been charged with 1,480 misdemeanors -- two violations for each day the city said he lacked the proper approvals.

One neighbor who complained about the size of Economides's house and brick retaining wall reviewed city records on the project and noticed what appeared to be a demolition permit that had been altered. The lot and square number identified a different property, and the permit number matched one issued months earlier for the demolition of a house on Chain Bridge Road. The city inspector general's office is investigating the altered permit.

Economides said he has done nothing wrong and called the city's enforcement process "absurd." He said he used a permit expediting service, which he would not identify, to obtain the demolition permit and never examined it.

"It's ridiculous to think we were trying to go through the back door," he said. He is scheduled for a jury trial Aug. 9 and said his family is eager to move into the new home, which was completed this month.

In recent months, the city has taken steps to strengthen the regulatory agency's enforcement powers. The agency, which has 50 inspectors and plans to hire 10 more, has created an Illegal Construction Unit, a team of inspectors whose shifts include nights and weekends to catch violators working at odd hours. In addition, the D.C. Council has given preliminary approval to legislation that would increase fines from $300 to $2,000 per violation and raise the maximum jail time from 10 to 90 days.

Over the past six months, six people working on projects in the Capitol Hill, Shaw or Deanwood neighborhoods have been arrested, primarily on charges of removing stop-work orders and continuing construction.

Jefferey Keil, a longtime contractor in the District, was arrested in March and accused of building in Northwest without a permit, violating a stop-work order and removing the order. Keil's attorney, Richard Bianco, said that his client was wrongfully arrested and that a permit had been obtained a week earlier.

"How can you arrest somebody for working pursuant to a permit that DCRA issued?" Bianco asked.

Cyrus C. Blackmon and his wife, Katarina Varani, were arrested at their Capitol Hill home in April and charged with building without a permit, removing stop-work orders and entering a property in violation of a stop-work order. Records show that inspectors had posted four stop-work orders at the couple's home and that the signs were ripped down, one of them less than an hour after it was put up.

The couple declined to be interviewed but denied wrongdoing in an appeal to the city's Office of Administrative Hearings, which dismissed some of their fines. Documents filed with the city show they had complained that their contractor failed to obtain permits. The couple has a court hearing scheduled for next month in the criminal case.

One report of illegal construction activity can quickly lead to other violators being cited.

Alerted by a neighbor, the agency's inspection unit recently discovered that Oladele had been constructing a four-story, multiunit building at 723 Morton St. NW since 2003 without a building permit. Inspectors immediately posted a stop-work order.

Then they noticed that a homeowner across the street was renovating his house without permits. They halted that work, too. D.C. police officer Kevin E. Brittingham, the property owner, has received $10,000 in fines and penalties. He said he is appealing the fines because he didn't know he needed a permit to remodel his kitchen and replace windows.

"I know now," he said.

Staff researcher Bobbye Pratt contributed to this report.

Frank Economides, who had this 9,000-square-foot home built in Northwest after demolishing his previous home, is charged with failing to obtain valid permits. He denies wrongdoing and says the city mishandled his case.