77 Ill. Adm. Code 870.TABLE D
D Footing Areas Required for Soil's Load-Bearing Capacity - Design Roof Load 40 Pounds Per Square Foot
Section 870.TABLE DĀ Ā Footing Areas Required for Soil's
Load-Bearing Capacity ā Design Roof Load 40 Pounds Per Square Foot
Section Width (feet)
12
14
16
12
14
16
12
14
16
Support Spacing (feet)
6
6
6
8
8
8
10
10
10
Support Loading (pounds per pier)
3950
4650
5300
5300
6150
7050
6600
7700
8800*
Soil's Load- Bearing Capacity (lbs/ft
2
)
Footing Area (square inches)
1000
569
670
763
763
886
1015
950
1109
1267
1500
379
446
509
509
590
677
634
739
845
2000
284
335
382
382
443
508
475
554
634
3000
190
223
254
254
295
338
317
370
422
4000
144
167
191
191
221
254
238
277
317
a)Ā Ā Ā Ā Ā First
footing centered within 2 feet from end of home.
b)*Ā Ā Ā Individual
supports, concrete 8"x8"x16" blocks, shall NOT support loads
greater than 8,000 pounds for a single stack and 14,000 pounds for a double
stack pier.