Eichler and mid-century modern homes in Silicon Valley.

A mid-century modern tract home built by developer Joseph Eichler's company in California, mostly in the Bay Area, between 1949 and 1974. They're known for post-and-beam construction, walls of glass facing private yards, radiant heat in the floor slab, and, in later models, an open-air atrium at the center of the house.

Joseph Eichler (1900–1974) was a developer who hired progressive modernist architects to design homes for middle-class families, something builders of his era almost never did. He sold his company in 1966 but kept building until his death in 1974.

He also sold homes to buyers of any race or religion. In 1958 he resigned from the National Association of Home Builders when it declined to support a non-discrimination policy.

Robert Anshen of Anshen & Allen designed the first Eichlers in 1949. Later homes came from Claude Oakland & Associates in San Francisco and Jones & Emmons in Los Angeles, among others.

About 11,000 were built in California, most of them in the Bay Area. Palo Alto has the most of any city, about 2,700, followed by Sunnyvale, with more in San Jose, Mountain View, and Cupertino.

Hot water from a boiler runs through pipes cast into the concrete slab and warms the floor. Earlier systems used steel tubing, much of which corroded; later Eichlers used copper.

Leaks in copper systems can usually be repaired. Corroded steel systems generally can't be saved, so the heat has to be replaced, with options like a new in-slab system, radiant panels over the slab, ductless mini-splits, baseboards, or a rooftop unit. Before you buy, have a radiant specialist pressure-test the system and identify the pipe.

There's no attic: the roof is the exposed wood ceiling with waterproofing on top. The originals had very little insulation under tar and gravel, so the homes ran hot and cold.

Many owners reroof with spray foam, which insulates and waterproofs in one layer and gets a protective coating that needs periodic renewal. Ask the seller for the roof's age, material, permits, and recoat history.

Original single-pane glass loses heat in winter and gains it in summer. Dual-pane or low-e glass makes the house more comfortable; the trick is keeping the slim original frame profiles.

Homes of this era can. Original vinyl floor tile and the black adhesive under it often contain asbestos, and homes built before 1978 come with federal lead-paint disclosure rules. Test before you sand, remove, or disturb old materials, and use licensed professionals for abatement.

The ones that hurt most are hard to undo: painting over exposed beams, tongue-and-groove ceilings, or the original mahogany paneling, and all-white remodels that strip out the warmth. Once wood is painted, it's painted for good.

The ones that help keep the character and fix the problems: restoring paneling, repairing the post-and-beam structure, and upgrading the roof, glass, and heating in ways that keep the original lines. Buyers who seek out Eichlers notice the difference.

Beams that run past the roof edge face the weather. Once the paint wears through they can crack, absorb moisture, and develop dry rot or termites. Rot confined to the ends can often be repaired without replacing the whole beam.

Green Gables and Greenmeadow in Palo Alto were listed as historic districts in 2005, and San Jose's Fairglen Additions in 2019. Listing is mainly recognition; what you can change is controlled by local rules.

It depends on the city. Several Palo Alto Eichler neighborhoods have voted in single-story overlays that bar second stories, and Cupertino's Fairgrove tract has Eichler zoning with a single-story limit. Sunnyvale reviews Eichler additions under design guidelines.

What's allowed comes down to the city and the specific lot, so it's worth checking before you buy. It's one of the first things we'd look into together.