Installation Instructions for ABS Pads

Installation Instructions for ABS Pads A. The purpose of this section is to emphasize that the ground under the ABS pads must be leveled, evenly compacted, and cleared of all vegetation and debris before the placement of the pads and all pads are to be installed flat side down, ribbed side up. B. The maximum deflection in a single pad is 3/8 of an inch measured from the highest point to the lowest point of the top. If the ABS pad deflects more than 3/8” when installed with home’s dead load applied, it is an indication that a) the pier spacing is incorrect resulting in the improper weight distribution on the support pier and/or; b) the soil pad was not properly compacted resulting in the support pier settling due to the improper load bearing capacity of the soil. C. Installation Instructions for ABS Pads. 1. All pads are to be installed flat side down, ribbed side up. 2. The ground under the pads should be level and smooth with all vegetation removed. Pads are not to be placed on natural grade unless otherwise permitted by the local building authority. 3. Pier and pad spacing will be determined by the Factory-Built home manufacturer's written set up instructions. 4. The open cells between the ribbings on the upper side of the pads may be filled with soil or sand after installation to prevent any accumulation of stagnant water in the pads. 5. ABS pads can be used in multi-stack orientations to create a larger pad area and provide for wider pier spacing as shown in Figure 13 (consult manufacturer’s listing for proper uses). 6. A pocket penetrometer may be used to determine the actual soil bearing value. If soil testing equipment is not available, an assumed soil bearing capacity value of 2,000 lbs./square foot (psf) may be used. 7. All pad sizes shown are nominal dimensions and may vary to 1/8 of an inch. 8. The maximum deflection in a single ABS pad is 3/8 of an inch measured from the highest point to the lowest point of the top face of the pad. (Please review Table VI and Figure 14). Deflections of the ABS pads with the home’s dead load applied results from improper pier spacings, uneven soil or poorly compacted soil. TABLE VI – SIZE AND LOAD PAD SIZE PAD AREA 1000 LB. SOIL 2000 LB. SOIL 3000 LB. SOIL 16” X 16” 256 sq. in. 1,780 lbs. 3,560 lbs. 5,333 lbs. 18.5” X 18.5” 342 sq. in. 2,375 lbs. 4,750 lbs. 7,125 lbs. 20” X 20” 400 sq. in. 2,750 lbs. 5,500 lbs. 8,250 lbs. a. Any configuration of ABS pad sizes above may be used to replace a home manufacturer’s recommended concrete pad. b. The maximum load at any intermediate solid value may be determined as the average of the next lower and next higher soil values given in the above table. c. Pad sizes shown are nominal dimensions and may vary up to 1/8 inch. d. Pad loads are the same when using single stack or double stack blocks.