Nov. 6, 2006 — -- During the last few years, home builders have been constructing about 2 million brand new houses a year.
Ninety percent of buyers say they're happy with the homes. While that may sound like a huge figure, that means 200,000 customers a year are not happy with the biggest purchase of their lives.
Consumer complaints about builders have gone up more than 50 percent in the past five years, according to the better business bureau.
ABC News' Elizabeth Leamy asked home inspectors to go through some newly built houses and point out what they found wrong.
One Maryland house had drastic structural problems. The contractor shoved the main support beam through the outside wall when he couldn't get it to fit right on the other end.
Inside the house, inspector J.D. Grewell said the entire roof could come crashing down because it was installed wrong.
"This is to the point of let's start over, let's start rebuilding," he said.
Fortunately, the homeowners discovered these life-threatening flaws before the drywall went up and hid them from view.
"It has been a total nightmare," said Dennis Capolongo, owner of the Maryland home. "We are devastated. It has taken away lots of precious time from my family and friends."
Water worries plagued one Virginia house. Ever since it was completed a year and a half ago, the homeowners have heard water trickling "inside" their walls when it rains.
Inspector Ted Collins found large gaps around the windows where they should have been sealed, according to the manufacturer's own instructions. Mold isn't visible, but it's obvious where water has saturated the wall.
"The stains are as plain as day, right here in front of everybody," Collins said.
New Jersey investigators found these kinds of problems -- and worse -- during a two-year long investigation of the home construction industry.
"It is the single largest purchase that most people will make in their life times. It is absolutely devastating to them. We encountered people who have had marriages fall apart over the problems in the home," said Charlotte Gaal of the New Jersey Commission of Investigation.