Engineered Hardwood in Palo Alto

Palo Alto Conditions That Affect Engineered Hardwood

Derived statistic, not a published normal: averaging NOAA Local Climatological Data hourly observations at Palo Alto Airport across the ten Julys 2015-2024 (Local Standard Time) gives 86.6% relative humidity at 05:00 (n=250) and 62.7% at 16:00 (n=235). The station reports only between about 05:00 and 19:00, so no overnight figure exists for it. For contrast, NOAA's Comparative Climatic Data table gives Sacramento a July afternoon mean of 29%. Engineered hardwood exists precisely for climates like this. With Palo Alto summer highs near 79°F and air conditioning drying the house out, a cross-laminated or multi-ply core moves far less across the grain than solid wood does, so seasonal gapping is much less pronounced. It is the reason we recommend engineered over wide plank widths in particular — the wider the board, the more a solid version would move.

NOAA 1991-2020 normals at the Palo Alto station give January an average high of 57.8°F and an average low of 39.0°F; December's 38.6°F is the coldest average low. Annual precipitation normal is 15.12 inches, with February the wettest month at 3.18 inches. Through winter the same stability works in reverse: the core resists the swelling that a solid floor would show as the house takes on moisture. Stable is not inert, though — the expansion gap at the perimeter still gets set properly.

Palo Alto's July normal high of 79.4°F runs about 13°F above San Francisco Downtown (66.3°F) and just below San Jose's airport station (80.8°F). For engineered hardwood in Palo Alto, the conditions that matter most are under and inside the house: a subfloor confirmed dry before a glue-down, and indoor humidity inside the range the manufacturer specifies.

What Palo Alto's Humidity Asks of Engineered Hardwood

In Palo Alto the case for engineered hardwood rests more on plank width and slab than on climate, and the measurements show why. Hourly dewpoint readings from Moffett Federal Airfield, 5 miles away, put that air at a median 40.1% relative humidity once it is heated to 70°F over winter — 16% of those hours under NWFA's 30% minimum — rising to 61.2% in summer. A solid 5-inch white oak board living through that, at roughly 7.7% to 11.2% equilibrium moisture content, changes width by about 0.066 inch between seasons. A cross-laminated core exists to restrain that movement; how much it restrains depends on the product's construction, so we go by the manufacturer's stated humidity range for the specific floor rather than a general rule.

Source: Hourly ASOS dewpoint observations 2015–2025, Iowa Environmental Mesonet (Iowa State University); equilibrium moisture content from USDA Wood Handbook FPL-GTR-190 Eq. 4-5; movement from FPL-GTR-282 Eq. 13-3 and Table 13-5

Subfloor and Foundation Work

The city's adopted Eichler Neighborhood Design Guidelines (April 2, 2018) state that of the more than 11,000 homes Joseph Eichler built, 'some 2,700 were located in Palo Alto' — elsewhere the same document says 'well over 2,000' — across 31 tracts built between 1949 and 1974. As typical characteristics, the guidelines describe a 'post and beam construction method, built on a concrete slab foundation,' with 'Radiant heating is embedded in the concrete slab flooring,' and warn that the original radiant heating system 'may be difficult to repair without highly invasive intervention.' 70.0% of Palo Alto housing predates 1980. CRMP's 2025 Earthquake Brace + Bolt list, with eligibility 'based on ZIP Code only,' includes 94301, 94303, 94304 and 94306, ZIPs that contain Palo Alto addresses, for a program limited to 'wood-framed, pre-1980 homes with a raised foundation.'

Over a crawlspace, engineered goes down by nail, staple, glue, or float, so the method follows the subfloor rather than the other way round. We flatten the subfloor first — engineered plank is stiff, and it bridges dips instead of following them, which is what produces hollow spots underfoot.

Source: NAHB analysis of the Census Bureau Survey of Construction, foundation type by region (2024)

Palo Alto Homes We Work In

ACS 2020-2024 five-year estimates count 29,241 housing units, with a median year built of 1963. The 1950s alone account for 25.1% (7,341 units), the largest single decade. 13.3% were built in 1939 or earlier and 12.1% in the 1960s. 58.9% of the stock predates 1970. In Palo Alto's 1950s, pre-1940, and 1960s housing, engineered often wins on height as much as on moisture: a thinner assembly clears existing door jambs, appliance toe-kicks, and the transitions to rooms that aren't being redone, which matters when only part of the house is getting new floor.