Frost Line Depth in Worcester County, Massachusetts

  • Massachusetts state rule
  • Checked Oct 2026
  • Sources

State-set value

48in

122 cm · 4 ft

48 in (Massachusetts rule)

Set by the state: 780 CMR (10th ed.) Table R301.2(1).

Source and how we checked

Worcester County does not publish its own value; the state rule applies.

Document: mass.gov

Climate: 130 nights a year at or below 32 °F (NOAA 1991–2020, Worcester Regional Airport, 4.5 mi).

Checked Oct 2026. Report a correction

How deep is the frost line in Worcester County?

Massachusetts sets the frost footing depth for Worcester County at 48 in (122 cm). Footings, piers and other permanent supports must reach at least this depth (IRC R403.1.4.1).

Who sets the frost line depth in Worcester County?

Massachusetts writes this depth into its statewide residential code, so Worcester County’s building department enforces the state’s number rather than setting its own. See how Massachusetts sets frost line depth.

How deep do footings, decks and water lines need to be in Worcester County?

Project
House or garage footing in Worcester County: dig at least 48 in. grade 0 in 122436486072 12 in code minimum frost line 48 in dig 48 in

House or garage footing in Worcester County: dig at least 48 in (122 cm). Below the frost line and at least 12 in deep (IRC R403.1.4).

Minimum depths in Worcester County with a 48 in frost line
ProjectDepthRule
House or garage footing48 inBelow the frost line and at least 12 in deep (IRC R403.1.4)
Deck footing (attached)48 inBelow the frost line and at least 12 in deep (IRC R507.3)
Water service line54 in6 in below the frost line and at least 12 in deep (IRC P2603.5)
Fence post bottom48 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 Worcester County?

  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

Average lows are at or below freezing from Dec to Mar. 130 nights a year reach 32 °F or colder; Jan is coldest, with an average low of 17.1 °F.

NOAA 1991–2020 climate normals, Worcester Regional Airport station, 4.5 mi away, elevation 1,000 ft.

Monthly temperatures as a table
°FJanFebMarAprMayJunJulAugSepOctNovDec
Low17.118.92636.546.855.961.760.553.242.232.523.4
High32.335.14355.766.674.579.878.170.758.947.937.5
92166 nightsWorcester County 130

Worcester County has fewer freezing nights than 19 of the 38 other Massachusetts places we track. The Massachusetts median is 130. Coldest: Berkshire County; mildest: Malden.

How likely is the soil in Worcester County to heave?

USDA rates the sampled soil around Worcester County as 12% low, 75% moderate, 13% high for frost action (main soils: Canton, Paxton, Woodbridge).

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 Worcester County?

Worcester County at a glance

Frost line depth
48 in (Massachusetts rule)
Population (2023 est.)
866,866
Mean annual temperature
48.1 °F
ZIP codes (87)
01005 · 01010 · 01031 · 01037 · 01068 · 01074 · 01082 · 01083 · 01092 · 01094 · 01331 · 01366 · 01368 · 01420 · 01430 · 01434 · 01436 · 01438 · 01440 · 01451 · 01452 · 01453 · 01462 · 01468 · 01473 · 01475 · 01501 · 01503 · 01504 · 01505 · 01506 · 01507 · 01510 · 01515 · 01516 · 01518 · 01519 · 01520 · 01522 · 01523 · 01524 · 01525 · 01527 · 01529 · 01531 · 01532 · 01534 · 01535 · 01536 · 01537 · 01540 · 01541 · 01542 · 01543 · 01545 · 01550 · 01560 · 01561 · 01562 · 01564 · 01566 · 01568 · 01569 · 01570 · 01571 · 01581 · 01583 · 01585 · 01588 · 01590 · 01602 · 01603 · 01604 · 01605 · 01606 · 01607 · 01608 · 01609 · 01610 · 01611 · 01612 · 01740 · 01745 · 01747 · 01756 · 01757 · 01772