Building practices were different 15-years ago, which is why some experts say rotting homes may not be all that uncommon.

Tucked away off the coast of Hood Canal, Brant Mash's dream home was turning into a real-life nightmare.

"I definitely had high hopes that this would stand for 100 years," said Mash.

But rot and mold cover most of his two-story home. Some areas are so bad that the sheeting crumbles off.

"I can reach my arm all the way through. You can almost call it an environmental catastrophe," said Mash.

Mash was pressure washing the side of his house when he accidentally knocked off two shingles. That's when he discovered the rot.

"I ended up stripping the whole north wall and it ended with a real problem," said Mash.

Mash blames the house wrap -- a plastic covering that's supposed to protect the wood from getting wet.

"My opinion is that we have a house wrap that doesn't perform to a standard acceptable for humans to live in," said Mash.

So KIRO asked building expert Rick Cadwell to inspect the Mash home.

"Just taking a quick look at it, the house wrap material is supposed to be impermeable," said Cadwell.

Cadwell points to the tears and nail hole in the wrap. Cadwell says the moisture likely seeped in and got stuck. He says a short roof overhang and a lack of drainage played a role as well.

"I'd say it's not limited to just this house. This is kind of what everyone was doing 15 years ago," said Cadwell.

A number of contractors KIRO spoke with say the state energy code may be part of the problem. Codes dictate how a house is built.

"Does the energy code have anything to do with why homes in this area rot?" asked KIRO 7 Consumer Investigator David Quinlan.

"No, it doesn't, and it's been a myth for 30 years. What makes houses rot are openings in them," said Gary Nordeen with the Washington State University Extension Energy Program, who researches rot problems.

"It's been a pretty big problem for a number or years here," said Nordeen. Nordeen's tested dozens of walls for rot and mold, so, when we showed him Mash's house he said it may be a widespread problem -- rot and mold lurking between your walls and you don't even know it.

Quinlan: "In your honest opinion, do you think this is the only house out there like this?"

Nordeen: " No. I'd assume there are hundreds of houses out there like this."

Nordeen says that 15 years ago, drainage plans on homes were not as common. Nowadays, it's a must.

Quinlan: "What do you think happened to Brant mash's home?"

Nordeen: "Well, obviously it's moisture damage. I don't know if the house wrap failed or not. That's something a chemist will need to look at."

KIRO did talk with the manufacturer of the house wrap used on Mash's home who said they went to the house, took samples and ran tests. They told KIRO their product worked fine, and blamed the rot problem on bad building practices.

But Mash is not convinced.

"I designed the house," said Mash.

Mash says he followed industry standards and now worries that other homeowners could find themselves with the same rotten problem. And with two newborns, Mash must decide whether the house he built is still safe to live in or if he needs to demolish it and start over.

"We're a family on a budget and so we also need a place to live. So we have one mortgage we've got to deal with and we're not anxious to dive into a second one or a rental or whatever," said Mash.

The Mash's are in talks with their insurance company. It's going to cost a minimum of $200,000 to repair the home.

As far as checking your own home for rot, experts say look for signs of mold or black residue, discoloration and if your home's exterior shows signs of getting mushy, then you might want to call an inspector.