IN THE YEARS following 1989's Loma Prieta earthquake, many homeowners in the Bay Area hired contractors to seismically retrofit their homes. The process is relatively simple and can be quite effective in reducing earthquake damage if it is done properly.

Unfortunately, shoddy work has left many homes vulnerable to earthquakes, while homeowners believe they are protected.

An investigation by the Times of 35 retrofitted wood-frame houses in the East Bay revealed that more than two-thirds of the homes were lacking protection because of less-than-excellent work.

Details of that investigation can be found on the front page of today's edition.

The homes were inspected by two veteran building officials who serve on seismic safety boards. They found that with more than two-thirds of the homes they examined, the only thing homeowners got was a false sense of security. That is disappointing when one considers that properly retrofitting a wood-frame house is not that difficult or expensive.

There are three basic elements to the retrofitting process: bolting the home to its foundation and using firm plywood shear walls and braces that strongly tie shear walls to the home's first floor.

If done right, these three things can prevent walls from shifting and keep houses from sliding off their foundations and collapsing. Proper retrofitting can save lives and tens of thousands of dollars or more in damages.

If a home remains on its foundation and the supporting walls hold up, earthquake damage can be relatively limited. But the retrofitting must be done properly.

Homeowners might ask contractors just what is the California standard for reliable earthquake retrofitting projects. Amazingly, the answer is that there is no standard.

Despite the Loma Prieta quake and predictions of the likelihood of a major earthquake on the Hayward or San Andreas fault in the next couple of decades, the state has not done a thing about setting a standard.

As a result, much of the retrofitting work has fallen short of what is needed to fully protect a home. The inspectors who aided the Times' investigation found a host of problems, many of which would be relatively easy to fix.

Nails were either too small to make strong connections or too large, which can split wood. Reinforced walls, also known as shear walls, were weakened by driving nails too deeply into the plywood.

Often nails into the plywood shear walls missed the beams. Some shear walls were made of small pieces of plywood rather than a large sheet, which is essential for stabilizing a home during a quake.

Exterior walls were not properly attached to the foundation. The same was true of shear walls, which were improperly attached to the floor beams.

Brackets that attached shear walls to beams were too small to withstand the forces of earthquakes.

Houses built before 1940 are most vulnerable. But it wasn't until 1978 that building codes for new construction required seismic safety compliance. Homes built before then should be inspected for their vulnerability to earthquakes and have proper retrofitting done.

But with no state codes specifying what needs to be done to effectively protect a home from earthquake damage, contractors are free to do what they want. Too often their work is insufficient, and homeowners are unaware of their exposure to significant loss.

California, like every other state, has many building codes that must be followed, but earthquake retrofitting is not addressed.

To correct the situation, the Legislature would have to enact a law to specify new regulations regarding retrofitting of homes. Developing a statewide standard should not be overwhelming. The basic elements of retrofitting are well-known and not difficult or overly expensive to accomplish.

But more than 16 years after the Loma Prieta earthquake, there has been no successful effort to legislate retrofitting standards that could save tens of thousands of homes from being devastated by an earthquake that is sure to come.

Fortunately, cities and counties do not have to wait for the Legislature to act. They can develop their own standards and should do so as quickly as possible. But they would be only stopgap measures.

It is long past time for the Legislature to enact an effective retrofit standard for all of California. Not only would it protect lives and homes, but it could lower earthquake insurance rates for owners of older homes with proper retrofitting.

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