Centex hired companies specializing in retaining walls to build and then rebuild a retaining wall in San Antonio that failed Jan. 26, causing the collapse of a slope supporting 91 homes, Pulte, Centex's parent company, said in the wake of news reports that the builder did not get a permit for the wall's construction.

"The retaining wall was constructed by a company that specializes in the construction of retaining walls," the Pulte statement said. "That company constructed the retaining wall following construction plans prepared by an engineer licensed by the state of Texas. We have every reason to believe that the retaining wall was built in accordance with those engineered plans because the construction process was supervised continuously by an independent geotechnical engineer."

"It is the company's belief that Centex followed industry standards, and we have reached out to the city to better understand the issue."

The company said Centex had the retaining wall rebuilt in 2007 after it had indications it "was not performing to expectations." During the rebuild, the wall's foundation was "substantially" reinforced, again using plans by a licensed professional engineer designed for the specific location.

"The wall was built in accordance with those plans and supervised by the engineer and separate geotechnical engineers," Pulte said.

Centex is working to stabilize the homes and has begun an investigation into what happened, engaging "well-respected" engineering firms and soil professionals.

Pulte said 66 families have been allowed to return home. Another 25 families are still displaced, but they have been allowed to collect their personal belongings from their houses.

"Centex expects about half of them will be able to return to their homes within the next 10 to 15 days." In the meantime, the company is providing for the homeowners' lodging and meals and covering incidental expenses, the statement said.