Architects have something new to worry about. The California Supreme Court ruled that two large firms, Skidmore, Owings & Merrill (SOM) and HKS Architects, could be forced to pay damages to an association of condominium owners who claimed their apartments were too hot—years after the developer rejected the architects’ recommendation to use low-E glass.

The case has yet to go to trial, but the decision may open the door to lawsuits by property owners who are unhappy about design decisions made at the request of previous owners. The case was considered so important that the American Institute of Architects California Council (AIACC) filed an amicus brief on the side of SOM and HKS, with support from the AIA in Washington, D.C. And while the ruling applies only in California, that state’s supreme court influences judges in other states.

The project that led to the lawsuit is the Beacon, a four-building, 595-unit condo complex in the China Basin section of San Francisco. SOM, through its San Francisco office, was design architect; HKS, based in Dallas, was architect of record. (Together, the firms earned fees of more than $5 million, which did not escape the court’s attention.) Four years after the building was completed, the Beacon Residential Community Association, unhappy with temperatures in some of the apartments, sued. “The glass recommended by SOM would have prevented the problem, but the developer substituted lower-performance glass” to reduce costs, says SOM spokesperson Elizabeth Kubany.

In prior cases, California courts had ruled that an architect owes no duty of care to “downstream” users. This time, the court held that such a duty exists, in part because architects, in the court’s view, are uniquely qualified to choose the right building materials. The decision cleared the way for the six-year-old lawsuit to move forward. Says Kubany, “I am confident that SOM will be fully vindicated at trial.” Perhaps. But the court’s ruling will affect many other firms. R. Craig Williams, a principal of HKS (and the firm’s chief legal officer), says that the decision means that HKS “should have known better than do what the client demanded.” Kurt Cooknick, the Director of Regulation and Practice of the AIACC, agrees: “The architect will be put in a bad position if the current client wants him to do something that will affect the downstream owner.”

Of course, not everyone is lamenting the decision. Ann Rankin, an attorney whose firm represents the residents, calls it “a big win for property owners throughout California whose buildings suffer from design errors caused by the negligence of architects and engineers.” And even some design professionals agree with the decision. Howard I. Littman, a forensic architect in Agoura Hills, California, says that architects should hold themselves to a high ethical standard, and not expect to be relieved of liability because a negligently designed building happened to change hands.