Frostline.info

Frost line depth in Tarrant County, Texas

Frost reaches about 9 inches in typical soil across Tarrant County, from 8″ in the mildest ZIP code to 11″ in the coldest. Codes in this climate commonly set footing depth at 12 to 18 inches.

Shallow frost
Estimated frost depth
9″
typical silt/loam soil
Typical code footing depth
12–18″
rule of thumb for this climate
Design freezing index
89
°F-days, 100-year winter
ZIP codes covered
65
#91 of 255 counties in TX (1 = deepest)
9″ 0″12″24″36″ ground frozen
Est. frost (typical soil) Typical code footing depth Clay–sand range

Frost depth by soil type

Soil typeEst. frost depth
Sand / gravel (drains well)12″
Silt / loam (typical yard soil)9″
Clay (holds water)8″

County average. Methodology.

Verify before you dig. These are climate-based estimates. The legally required frost depth is the figure your building department publishes in its IRC Table R301.2 (climatic and geographic design criteria). Call the Tarrant County building or permitting office in Texas and call 811 before digging.

Frost depth by ZIP code in Tarrant County

ZIPCityEst. frostCode range
75054Grand Prairie8″12–18″
76001Arlington8″12–18″
76002Arlington8″12–18″
76005Arlington10″12–18″
76006Arlington9″12–18″
76010Arlington9″12–18″
76011Arlington9″12–18″
76012Arlington9″12–18″
76013Arlington8″12–18″
76014Arlington8″12–18″
76015Arlington8″12–18″
76016Arlington8″12–18″
76017Arlington8″12–18″
76018Arlington8″12–18″
76020Azle11″12–18″
76021Bedford9″12–18″
76022Bedford9″12–18″
76034Colleyville9″12–18″
76036Crowley9″12–18″
76039Euless9″12–18″
76040Euless9″12–18″
76051Grapevine9″12–18″
76052Haslet10″12–18″
76053Hurst9″12–18″
76054Hurst10″12–18″
76060Kennedale9″12–18″
76063Mansfield8″12–18″
76092Southlake9″12–18″
76102Fort Worth10″12–18″
76103Fort Worth9″12–18″
76104Fort Worth10″12–18″
76105Fort Worth9″12–18″
76106Fort Worth10″12–18″
76107Fort Worth10″12–18″
76108Fort Worth10″12–18″
76109Fort Worth10″12–18″
76110Fort Worth9″12–18″
76111Fort Worth10″12–18″
76112Fort Worth8″12–18″
76114Fort Worth10″12–18″
76115Fort Worth9″12–18″
76116Fort Worth10″12–18″
76117Haltom City10″12–18″
76118Fort Worth9″12–18″
76119Fort Worth9″12–18″
76120Fort Worth9″12–18″
76123Fort Worth9″12–18″
76126Fort Worth10″12–18″
76127Naval Air Station Jrb10″12–18″
76131Fort Worth10″12–18″
76132Fort Worth10″12–18″
76133Fort Worth9″12–18″
76134Fort Worth9″12–18″
76135Fort Worth11″12–18″
76137Fort Worth10″12–18″
76140Fort Worth9″12–18″
76148Fort Worth10″12–18″
76155Fort Worth9″12–18″
76164Fort Worth10″12–18″
76177Fort Worth10″12–18″
76179Fort Worth11″12–18″
76180North Richland Hills9″12–18″
76182North Richland Hills10″12–18″
76244Keller10″12–18″
76248Keller10″12–18″

What this means for your project in Tarrant County

Deck footings & piers

Footings must bear below the frost line and at least 12″ below undisturbed ground. For planning in this area, budget for holes around 18″ deep until your permit office confirms the exact figure.

Fence posts

Set posts at least one-third of their above-ground height. Where frost heave is a problem, carry concrete footings below the frost line (about 12″ here in typical soil) and bell or taper the bottom.

Water & irrigation lines

Bury supply lines below the frost depth. Your water utility or plumbing code sets the minimum cover; freezing is rare, but exposed pipes still need insulation.

Slabs & frost-protected foundations

Frost-protected shallow foundations (IRC R403.3) use the 100-year air freezing index — 89 °F-days here — to size perimeter insulation, letting footings sit shallower than the frost line.

Weather stations used

NOAA weather stationDistance100-yr AFI
Cleburne, TX31 mi63
Denton 2 Se, TX31 mi84
Weatherford, TX33 mi137
Waxahachie, TX34 mi77

Nearby counties

Common questions

What is the frost line depth in Tarrant County?

About 9 inches in typical soil, based on NOAA's 100-year air freezing index. Across the county's ZIP codes the estimate runs from 8 to 11 inches.

How deep should footings be in Tarrant County, Texas?

Codes in climates like this commonly require 12 to 18 inches. The Tarrant County building department publishes the required frost depth in its adopted code (IRC Table R301.2).

Does frost depth vary within Tarrant County?

Very little. Estimates across the county stay within 3 inches. Soil type matters more than location here.