Frost Line Depth in Allen, Texas
- Allen’s adopted code
- Checked Oct 2026
- Sources
Verified
6in
15 cm · 6 in
Set in the building code Allen 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: 48 nights a year at or below 32 °F (NOAA 1991–2020, Mckinney Municipal Airport, 6.8 mi).
Checked Oct 2026. Report a correction
How deep is the frost line in Allen?
Allen's building authority sets the frost line depth at 6 in (15 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 Allen?
Texas leaves the frost line depth to each city or county, and Allen fills it in when it adopts the residential code. The value above comes from Allen’s own document on library.municode.com. See how Texas sets frost line depth.
How deep do footings, decks and water lines need to be in Allen?
House or garage footing in Allen: dig at least 12 in (30 cm). Below the frost line and at least 12 in deep (IRC R403.1.4).
| Project | Depth | Rule |
|---|---|---|
| House or garage footing | 12 in | Below the frost line and at least 12 in deep (IRC R403.1.4) |
| Deck footing (attached) | 12 in | Below the frost line and at least 12 in deep (IRC R507.3) |
| Water service line | 12 in | 6 in below the frost line and at least 12 in deep (IRC P2603.5) |
| Fence post bottom | 12 in | No 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 Allen?
- J
- F
- M
- A
- M
- J
- J
- A
- S
- O
- N
- D
Allen never averages a low below freezing. 48 nights a year reach 32 °F or colder; Jan is coldest, with an average low of 33.9 °F.
NOAA 1991–2020 climate normals, Mckinney Municipal Airport station, 6.8 mi away, elevation 580 ft.
Monthly temperatures as a table
| °F | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Low | 33.9 | 38.1 | 45.5 | 53 | 62.4 | 70.2 | 73.8 | 73.1 | 65.5 | 54.2 | 43.7 | 35.8 |
| High | 55.5 | 59.7 | 67.5 | 74.7 | 82.8 | 90.7 | 95 | 95.5 | 88.3 | 77.9 | 66.2 | 57.1 |
Allen has more freezing nights than 143 of the 168 other Texas places we track. The Texas median is 32. Coldest: Amarillo; mildest: Brownsville.
What frost line depth do towns near Allen use?
5 official codes near Allen are verified; each links to its document.
| Place | Verified frost line | Distance |
|---|---|---|
| Frisco | 6 in | 9 mi away |
| Richardson | 6 in | 10 mi away |
| Lewisville | 6 in | 18 mi away |
| Denton | 6 in | 28 mi away |
| Keller | 6 in | 34 mi away |
How likely is the soil in Allen to heave?
USDA rates the sampled soil around Allen as 100% none for frost action (main soils: Houston Black, Heiden, Stephen).
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 Allen?
Allen at a glance
- Frost line depth
- 6 in
- County
- Collin County
- Population (2023 est.)
- 111,620
- Mean annual temperature
- 65 °F
- ZIP codes (3)
- 75002 · 75013 · 75025