Foundation, soft-story and the Hayward fault: selling a San Jose house that needs seismic work
The first thing I ask when someone calls about a foundation is what year the house was built and whether they can see dirt under it. Those two answers sort most of San Jose into two piles.
Pile one is the raised foundation. The 1940s and 1950s ranches in Willow Glen, Cambrian and Burbank, and the older streets of Santa Clara and Campbell. Concrete perimeter, a crawl space you slide into on your back, and short stud walls (cripple walls) between the sill and the floor joists. Pile two is the slab. Eichlers in Fairglen and Fairmeadow, and most tract houses after about 1960. No crawl space, radiant pipes cast into the concrete, and nothing to bolt because the floor is the foundation.
What's actually in a San Jose foundation bid
A proper bid from a licensed contractor breaks the work into line items you can compare across companies. Check the license on the Contractors State License Board site before you sign anything. Here's what mine looked like for a raised ranch.
Anchor bolts come first. The mudsill is the wood plate sitting on the concrete, and it gets bolted down to the foundation. We priced that per bolt. Whether epoxy or expansion bolts will hold depends on the concrete, and you don't know until somebody drills.
Then cripple wall bracing. Structural plywood nailed to the inside of those short walls in a set nailing pattern, plus hold-downs and blocking. This is what keeps the house from sliding off its foundation in a strong shake. Priced by the linear foot.
Then piers. Where the perimeter or the interior girders have settled, we cut out the failed section, dig, and pour new concrete piers, sometimes with steel adjustable posts. Priced per pier. The count is where bids swing wildly. A Cambrian ranch in 2016 had bids from eight piers to twenty-two, the seller went with the cheap one, and the buyer's engineer found the other fourteen during escrow. That was an ugly week.
Then drainage, and nobody wants to pay for it. It is also why the foundation moved in the first place. Downspout extensions, a French drain, maybe a sump. If a bid has no drainage line on it, ask why.
An Eichler on a slab is a different list. Slab cracks, radiant line leaks undermining the slab, post-and-beam connections, and glass walls that give the house almost no shear strength in one direction. That retrofit is real engineering, not a plywood job, and the bid should have an engineer's name on it.
How the faults show up in your paperwork
Buyers in Santa Clara County get a natural hazard disclosure report, and two boxes on it come straight from state geology.
The first is the Alquist-Priolo Earthquake Fault Zone. The California Geological Survey maps these zones as bands along active fault traces where the ground itself can rupture. The Hayward fault runs up the East Bay through Fremont. The Calaveras runs along the east side of the valley past Alum Rock and down toward Morgan Hill. If your parcel sits inside one of those bands, the report says so.
The second is the Seismic Hazard Zone for liquefaction or landslide. The CGS seismic hazards program maps the flat, wet, sandy ground where soil can lose its strength in a strong quake. In San Jose that's the low ground along the Guadalupe River and Coyote Creek, the Alviso side, and pockets of north San Jose. The landslide zones follow the foothills.
The USGS Earthquake Hazards Program publishes the shaking models everyone else copies from. None of it is a secret. Your job is to make sure the listing doesn't contradict the report.
What buyers' inspectors flag
On a 1950s ranch: an unbolted sill, no plywood on the cripple walls, a girder sitting on a stack of bricks, efflorescence on the stem wall, standing water in the crawl space in the wet months. Also any living space over a garage with a wide door opening under it. That is the single-family version of a soft story, and inspectors call it out even though soft-story ordinances are aimed at apartment buildings.
On an Eichler: cracks you can slip a dime into, and a slab that's warm in one spot and cold in the next, which is a radiant leak.
Inspectors don't price the fix. They write "recommend evaluation by a licensed structural engineer or foundation contractor," and the buyer's agent turns that sentence into a credit request.
What a retrofit does for value, and what it doesn't
It makes the house safer and cheaper to insure, and it takes one line off the inspection report.
It doesn't raise the sale price by what you paid. Not once in fifteen years of bids. Say the house would list at $1,400,000 with a clean foundation and you spend $60,000 on bolts, plywood and twelve piers. You don't now own a $1,460,000 house. You own a $1,400,000 house that a lender will finance without a fight, which is worth something, but nowhere near what you wrote the check for.
Earthquake insurance is the other piece. The California Earthquake Authority writes most of the residential earthquake policies in the state through participating insurers, and a bolted, braced house gets a lower rate than an unbraced one. There's also a brace-and-bolt grant program. The amounts and eligible ZIP codes change, so check the current rules before you count on it, and ask your tax person about the grant money, because I'm not one and none of this is legal or tax advice. Read Ready.gov's earthquake page while you're at it. The house is not the only thing that needs a plan.
When to sell as-is instead
This is the fork I walked people through at the kitchen table.
Finance the retrofit and then list if the foundation is the only real problem, the numbers are under six figures, you have the cash or a HELOC, and you can wait out the permit and inspection cycle. That cycle is measured in months.
Don't if the foundation is one problem among several. Or if the bids are all over the map. Or the house sits in a liquefaction zone no plywood will fix. Or you're selling because of a death or a move that already has a date on it. In that case the retrofit is a project you're running for the next owner, on your money and your calendar.
There's a middle road. If you need to sell a San Jose house with foundation problems without a lender in the picture, a cash buyer reads the pier count, knocks it off the price, and there's no lender asking for plywood before close.
My own recommendation
If the crawl space is wet, the bids are fighting each other and your own life is already pointed somewhere else, I'd sell the house instead of financing the retrofit. Get the bids anyway, from licensed people, with pier counts, and hand them to whoever buys. Then the concrete is somebody else's problem.