Frost Line Depth in Mountain View, California

  • Mountain View’s adopted code
  • Checked Oct 2026
  • Sources

Verified

0in

No frost depth required

Set in the building code Mountain View has adopted.

Footings still go at least 12 in (30 cm) below undisturbed ground (IRC R403.1.4).

Source and how we checked

Document: library.municode.com

Climate: 2 nights a year at or below 32 °F (NOAA 1991–2020, Moffett Federal Airfield, 1.8 mi).

Checked Oct 2026. Report a correction

How deep is the frost line in Mountain View?

Mountain View's building authority sets the frost line depth at 0 in (0 cm). Footings, piers and other permanent supports still go at least 12 in below undisturbed ground (IRC R403.1.4).

Who sets the frost line depth in Mountain View?

California leaves the frost line depth to each city or county, and Mountain View fills it in when it adopts the residential code. The value above comes from Mountain View’s own document on library.municode.com. See how California sets frost line depth.

How deep do footings, decks and water lines need to be in Mountain View?

Project
House or garage footing in Mountain View: dig at least 12 in. grade 0 in 122436486072 12 in code minimum frost line 0 in dig 12 in

House or garage footing in Mountain View: dig at least 12 in (30 cm). Below the frost line and at least 12 in deep (IRC R403.1.4).

Minimum depths in Mountain View with a 0 in frost line
ProjectDepthRule
House or garage footing12 inBelow the frost line and at least 12 in deep (IRC R403.1.4)
Deck footing (attached)12 inBelow the frost line and at least 12 in deep (IRC R507.3)
Water service line12 in6 in below the frost line and at least 12 in deep (IRC P2603.5)
Fence post bottom12 inNo code rule; common practice is below the frost line

Work out posts, concrete and footing sizes with the fence post depth calculator or the deck footing calculator.

How cold does it get in Mountain View?

  1. J
  2. F
  3. M
  4. A
  5. M
  6. J
  7. J
  8. A
  9. S
  10. O
  11. N
  12. D
0°32°100° J F M A M J J A S O N D 32 °F

Mountain View never averages a low below freezing. 2 nights a year reach 32 °F or colder; Dec is coldest, with an average low of 42.1 °F.

NOAA 1991–2020 climate normals, Moffett Federal Airfield station, 1.8 mi away, elevation 39 ft.

Monthly temperatures as a table
°FJanFebMarAprMayJunJulAugSepOctNovDec
Low42.444.546.748.952.555.758.55957.353.146.342.1
High5961.8656871.775.976.976.977.774.165.558.9
097 nightsMountain View 2

Mountain View has fewer freezing nights than 114 of the 208 other California places we track. The California median is 3. Coldest: El Dorado County; mildest: San Diego.

What frost line depth do towns near Mountain View use?

5 official codes near Mountain View are verified; each links to its document.

0″12″24″36″48″37 mi0 miPalo Alto: 5 in, 4 miCampbell: 12 in, 11 miDublin: 12 in, 24 miSanta Cruz: 12 in, 29 miWatsonville: 12 in, 37 mi
Official frost line depths near Mountain View
PlaceVerified frost lineDistance
Palo Alto 5 in 4 mi away
Campbell 12 in 11 mi away
Dublin 12 in 24 mi away
Santa Cruz 12 in 29 mi away
Watsonville 12 in 37 mi away

How likely is the soil in Mountain View to heave?

USDA rates the sampled soil around Mountain View as 100% none for frost action (main soils: Urban land, Aquic Xerorthents, Novato).

USDA NRCS soil survey, 9 sample points within 2 mi. Higher frost action means more risk of heave; see frost heave.

How do you confirm the frost line before you dig in Mountain View?

Mountain View at a glance

Frost line depth
0 in
County
Santa Clara County
Population (2023 est.)
81,785
Mean annual temperature
59.9 °F
ZIP codes (7)
94024 · 94040 · 94041 · 94043 · 94085 · 94303 · 94306