Shifting Soils causing
Foundation & Retaining Wall Failures elsewhere in Texas and the U.S.
This article collection expands on the one specific to Hills of Rivermist in San
Antonio
The high profile retaining wall collapse in The Hills of Rivermist is not unique to that subdivision
or to Centex-Pulte. Other locations and builders across the nation show signs of poorly built
retaining walls too, and this page will track them.
More homes suffering from foundation problems
By KATE MURPHY, The New York Times, 3/06/2010
http://seattletimes.nwsource.com/html/realestate/2011259620_realfoundations07.html

Steven Derse, the owner of a corporate travel business in Nashville, Tenn., cannot feel his
house move, but he can hear it.
"It's an eerie creaking sound," he said, and it echoes
throughout his two-story Georgian-style house.
It started two years ago when a severe drought contracted the soil beneath the foundation, which caused it to
crack and sink, pulling the house down with it.
The noise has continued intermittently, becoming more insistent last year when flooding pushed the already
compromised foundation and house back upward.
This seesawing effect was noisy and expensive. Derse has
spent more than $10,000 to install subterranean piers to stabilize his foundation, and he expects he will have to
install more to prevent further cracking and crumbling. [HOT: The effect is
caused by dome heave and edge heave as described in Soil Issues for Residential
Construction in Texas.]
"You lose your sense of security," he said. "You love your home and then it literally turns on
you."
His is not the only house buffeted by shifting soil. Extreme weather possibly linked to climate change, as well
as construction on less-stable ground, has provoked unprecedented foundation failures in houses nationwide.
Foundation-repair companies report a doubling and tripling of their business in the last two decades with no
letup even during the recession
"We've seen a tremendous influx of pretty severe cases due to either drought or too much
rain," said Dan Jaggers, vice president of technical services at Olshan
Foundation Repair, which has offices in the South, Midwest and Great Plains.
"People call panicked because they've got gaping cracks in their
walls, tile breaking, grout popping and they don't know what to do."
Other telltale signs of foundation failure include doors and windows that will not close, chimneys or porches
separating from the house and bowing basement walls.
After a particularly dry summer followed by deluges in the fall, Psonya Wilson, a lawyer in
Brandon, Miss., noticed light streaming in where the wall had separated from the baseboard in the bedroom of her
5-year-old son.
"I could stick my finger through it," she said. "I couldn't believe it. The whole back part of
the house had sunk about 6 inches."
To stop further collapse, not to mention to control the draft, she is having several stabilization piers
installed to shore up the foundation of her two-story garden style house; it will cost more than
$5,000.
Clay soils, like those beneath the houses of Derse and Wilson,
shrink during droughts and swell during floods, causing structures
to bob. [Expansive clay soils can swell as much as 30% and exert pressures
up to 15,000 pounds per square foot. For perspective, a concrete truck weighs about 20,000
pounds.]
And because sandier soil loses its adhesive properties in dry conditions, it pulls away from foundations.
Heavy rains cause it to shift or just collapse beneath structures. With both kinds of soil, such sinking, called
subsidence, usually happens gradually, said Randall Orndorff, a geologist with the U.S. Geologic
Survey.
But, he said, "swinging from very wet to extremely dry weather like we've been seeing lately in many parts
of the country may be accelerating the effect."
Subsidence is not covered by most homeowners' insurance policies in the United States, unlike in Britain, where
the increasing number of homeowners' claims due to foundation failure prompted the Charter Insurance Institute, an
industry-trade group, to issue a dire warning about the financial drain in its 2009 report, "Coping with
Climate Change: Risks and Opportunities for Insurers."
"The question we need to ask is, are we building to cope with the enhanced weather events related to climate
change," said Brenda Ekwurzel, a climate scientist with the Union of Concerned
Scientists, a nonprofit group advocating science-based solutions to environmental and health issues.
[Don't blame cracked foundations on Global Warming or an act of God. It's more likely
due to soil conditions that the builder SHOULD have known about, since checking the USDA Web Soil Survey is free.]
"It's obvious that we need to look at changing building codes
worldwide to deal with this."
Compounding the problem is that, during the recent housing boom in the United States, houses were built in areas
where the soil was particularly prone to shift.
"If you think about it, the best ground in cities is usually taken early on, so the builders and developers
have often been expanding into less-desirable areas, and in their rush to make money, may not have designed
structures to deal with it," said David Lourie, a geotechnical engineer in New
Orleans.
Fixing a failed foundation usually involves hiring a foundation-repair company to install cement or steel piers
around the perimeter of the house's slab or near its existing piers if it is a pier-and-beam foundation.
Once in place, hydraulic jacks lift and level the house and transfer its weight to the new supports.
The cost depends on the severity of the problem but generally runs about $1,000 to $2,000 per pier, which should
include a lifetime transferable warranty.
"It's amazing to watch your house get jacked up like that," said Miguel Rivera, a
designer of heating and air-conditioning systems, who had to pay $13,000 to have his 60-year-old house in West
Orange, N.J., shored up in January.
"It's just immediate. You're like, 'Whoa, up it goes.' "
His dining room began separating from the rest of his house about five years ago after repeated heavy rains
shifted the earth beneath it.
The problem was made worse when he removed a nearby tree, which was probably siphoning off excess water and
providing structure to the soil beneath his house.
"It often happens that you upset the moisture and structural balance when you knock down or tear out
trees," said Lourie, the geotechnical engineer, adding that planting trees too close to the house can be
harmful. "Plant them at least half their mature height away from the house."
Landscaping should, as a rule, be installed so that water slopes away from the house and gutters should
discharge at least 5 feet from the house to avoid oversaturating the soil.
During droughts, experts recommend placing soaker hoses around the perimeter of the house and turning them on 30
minutes a day.
"The idea is to maintain a constant amount of moisture in the soil," said Tom
Witherspoon, a foundation engineer in Dallas. "If you can do that, your house will never
move."
Foundations: Don't wait until you hear the creaking
By KATE MURPHY, The New York Times, 3/05/2010, http://seattletimes.nwsource.com/html/realestate/2011259571_realfoundationsbar.html
Engineering and structural-repair professionals say it is relatively easy to spot foundation problems in
structures that are more than 10 years old.
If you are considering buying an existing house, look for
patched-over cracks in brick or drywall and doors that have been planed. Also notice if there are cracks in
sidewalks and streets in the neighborhood.
In newer developments, it's harder to know if the homes will
withstand a shift in soil. Therefore, it might be a good idea to have a geotechnical engineer do an inspection — in
addition to having a normal home inspection — before you buy. [You can check the free
USDA Web Soil Survey first.]
Home inspectors may not have the expertise to assess soil conditions. (Licensed professionals can be found at
the Web site of the Associated Soil and Foundation Engineers, www.asfe.org)
This is especially important if you are considering buying a home in problematic areas. "My home inspector said
my house had no problems," said Steven Derse, who bought his house in Nashville, Tenn., in 2002. "Then it started
to move and fell apart like a cracker box."
Shifting Land Causes Wall Headaches In Cibolo
Residents Worried About Retaining
Wall
By Eileen Gonzales, KSAT 12 TV, 02/23/2010, http://www.ksat.com/news/22650908/detail.html#story
Watch Eileen Gonzales' Report
Another retaining
wall is causing problems for homeowners, this time in a Cibolo
subdivision.
Homeowners are worried about their safety and security, as they try to figure out where to turn to have the
problem fixed.
The problem is easy to see; along a utility easement, a line of uneven, unstable fences are shifting due to an
unstable retaining wall. Homeowner Nannette Neugart says the fence in her backyard completely
collapsed one Christmas Eve. Although the fence was fixed, the wall is still shifting and she said she's concerned
it will fall again.
Neighbors said they believe their safety and security are at risk.
"We're scared because ... my dogs can get through there," Neugart said. "My neighbor's afraid of his children being
in the backyard because of his children and the (fence) falling over at any moment."
Homeowners said they've been getting the runaround while trying to figure out who is to blame. The homeowners
association, subdivision developer Ryland Homes and the city all claim the other is
responsible.
"It's frustrating," Neugart said. "We don't know what to do any longer."
Neighbors said they have a stack of letters, dating back to October. They said their latest hope comes from Ryland
Homes, who promised to let them know if they'll help by the end of the week.
Neugart said she's heard this promise before and isn't convinced. For now, she said, it's wait and see.
KSAT called and left messages with Ryland Homes and the subdivision homeowners association, but as of Tuesday
afternoon, neither had returned calls.
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