Houses become a horror for Broomfield residents: Expansive soils expand into lawsuit

By Doug Cosper
Camera Staff Writer

Ed Ater’s problems began about 140 million years ago when volcanic ash rained down on his house site in Broomfield, which at the time was covered by an immense, shallow sea.

The problem – the ash, since turned to a scaly clay – became his soon after he and his wife picked up stakes in Amarillo, Texas, in 1990 and bought a new $150,000 home with a view of the mountains in the Ridgeview Heights subdivision.

About six months after moving in, Ater, a 50-year-old consulting engineer, noted the usual nicks and dings that come with a new home.

Then his concrete driveway developed cracks; the builder replaced it.

“Then I started seeing fissures in the basement floor.” The builder took care of it.

Ater spent $3,000 installing a bathroom in the basement. But six months later, the double doors wouldn’t work properly. Shower tiles cracked. The trim buckled.

Then the basement floor began to heave, swelling more than 6 inches in the center. Worse, cracks began to creep across a foundation wall. Upstairs, doors no longer would close, drywall cracked and walls became separated from ceilings. The carport slab swelled.

The Aters’ house was being shoved around like a toy by the ground it rested on – ground composed of expansive soils.

Now the builder, Broomfield’s Merit Homes, faces an expansive soils class action lawsuit that the company’s owners says would put him out of business.

Attorneys in the case believed scores of other homeowners could join the suit because of the prevalence of expansive soils across Broomfield and much of Boulder County.

Dangerous dirt

Volcanoes spewing ash during the Cretaceous period, the last age of the dinosaurs, deposited layers here of what became a clay that includes what is known as Montmorillonite and Bentonite, said University of Colorado Geology Professor Bill Atkinson.

“You could say it has sponge-like qualities,” he said.

The soils are composed of platelets, “like a stack of cards,” and under normal climatic conditions are fairly stable. But when exposed to excessive moisture, such as sprinkler systems soaking new lawns, water is absorbed between the layers, and the soil expands.

Gary Goodell, Builder county’s chief building official, calls the expansive clays “the Kleenex of soils.” Charles Bowman, a local private soils engineer, says such soils can expand as much as a fifth of their stable volume, but 5 percent to 8 percent is more common.

Once saturated, expansive soil can exert up to 15,000 pounds of pressure per square foot on a foundation wall or concrete floor, according to county figures.

Ater said the stuff underneath his basement slab looks like raw sourdough.

There are concentrations, or “hot spots” of expansive soil in Boulder County along the foothills, around Gunbarrel, Louisville, Superior, Lafayette and further southeast where Ater’s house stands, according to a county geologic hazards map.

It’s so widespread a soils report is required for every building permit issued in Boulder County.

Compounding the problem, expansive soils are “ultra site-specific,” the Boulder county Comprehensive Plan states. “The foundation materials under one end of a (house) may be highly expansive, whereas under the other, (they are) perfectly stable.”

But with proper engineering, the soils can be accommodated.

“Any problem with a clay deposit can be designed around if you’re willing to throw enough money at it,” Bowman said.

Up to one-third of new houses built in Boulder County are engineered for expansive soils, Goodell said. The most common accommodations include suspending the foundation on concrete piers that extend down by up to 40 feet to stable bedrock, and installing suspended, “structural” floors instead of concrete slabs poured directly over the earth.

And once a home is built, engineers recommend keeping the ground around the house as dry as possible by channeling away drainage and minimizing plants or grass that require extra water.

Settlement in millions

It’s those kinds of accommodations that are at the heart of the class action suit Ater and three of his neighbors filed in Boulder District Court against Merit Homes.

The suit says Merit’s soils engineers recommended structural floors in the homes, but that the company opted to install a less expensive slab-on-grade style.

Merit President John McCormac, who has built about 125 homes in Ridgeview Heights since 1979, says his company followed the engineer’s recommendations. “We rely on soils engineers and structural engineers to tell us how to do these things,” he said.

Of the suit’s negligence claim, Merit’s attorney, Robyn Kube, said, “We built to the standard of care at the time that the houses were built.”

Echoing McCormac’s frustration in dealing with the capricious dirt, Kube added, “It seems that engineering in this particular field is till an art, not a science.”

Ater’s attorneys, including a Denver firm that last year won multimillion dollar settlements in similar expansive soil suits against builders of the Highlands Ranch subdivision, have asked the Boulder court to allow a class action suit on behalf of Merit customers with similar complaints.

On behalf of potentially “hundreds” of Merit homeowners, Boulder lawyer Brad Peterson said, the suit would seek to recover damages including cost of repairs, loss of value and an unspecified dollar amount to make an example of Merit’s alleged mistakes.

If Ater and the others in the suit prevail, McCormac said, “Our position is that if insurance doesn’t cover it, we’re essentially out of business.”

But while McCormac continues to build on the troublesome soil- now with structural floors - Ater is bound up in a “Catch-22.”

“Here I am stuck with a house. I can’t sell it, and they won’t fix it.”

McCormac says his company has already pumped more than $25,000 into repairing Ater’s home – insurance has kicked in at least a like amount – but the problems remain.

“It’s been a nightmare,” a frustrated Ater said.

Just last month his teenage son shut the door to this bedroom and went to sleep for the night, he said. “By morning he’s asking me to push (the door) open. It was stuck in the jamb.”