Ill. Admin. Code tit. 77, § 870.TABLE D
a) First footing centered within 2 feet from end of home.
b)* 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.
| 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/ft2) | 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 |