Screw anchor foundations and related interfaces for modular, manufactured and prefabricated structures

Abstract

A foundation system for manufactured homes, prefabricated houses, and other structures. Multiple screw anchors are driven into the ground at the desired location of the structure. Preformed grade bars may be placed over the screw anchors to provide a modular foundation without pouring concrete or digging footers. Alternatively, adapters may be attached to one or more of the driven screw anchors to provide a pedestal to receive the grade bar or prefabricated sections of concrete

1 . A foundation system comprising:
 a first plurality of screw anchors; and   a second plurality of grade bar sections, each grade bar section comprising an elongated concrete structure adapted at each end to overlap with an adjacent grade bar section and to be supported from below by at least one of the first plurality of screw anchors.   
     
     
         2 . The foundation system according to  claim 1 , wherein each screw anchor comprises a head portion that is received in an opening formed in one of the grade bar sections. 
     
     
         3 . The foundation system according to  claim 2 , wherein a lower end of the head portion terminates in a support having a diameter wider than the opening. 
     
     
         4 . The foundation system according to  claim 3 , wherein the head portion is rotatable relative to the screw anchor portion to raise and lower the support relative to the screw anchor after the grade bar portion has been lowered over the head portion. 
     
     
         5 . The foundation system according to  claim 1 , further comprising a fastener passing through a portion of each overlapping grade bar section to join them together. 
     
     
         6 . The foundation system according to  claim 5 , further comprising at least one anchor bolt extending above at least one of the grade bar sections. 
     
     
         7 . A foundation system comprising:
 at least one screw anchor; and   at least one pre-cast concrete section that is supported by the at least one screw anchor at a pre-formed through-hole formed in the pre-cast concrete section.   
     
     
         8 . The foundation system according to  claim 7 , further comprising an adapter attached to an above-ground end of the at least one screw anchor for supporting the pre-cast concrete section at the pre-formed through-hole. 
     
     
         9 . The foundation system according to  claim 8 , further comprising an anchor bolt for joining the adapter to the pre-cast concrete section via the through-hole. 
     
     
         10 . The foundation system according to  claim 7 , wherein the pre-cast concrete section is a pre-cast concrete slab. 
     
     
         11 . The foundation system according to  claim 7 , wherein the pre-cast concrete section is a pre-cast grade bar. 
     
     
         12 . The foundation system according to  claim 7 , wherein the at least one screw anchor comprises an elongated hollow shaft with a thread form at one end and head portion at an opposing end. 
     
     
         13 . The foundation system according to  claim 12 , wherein the head portion terminates at a lower end in a support having a diameter larger than the pre-formed through-hole. 
     
     
         14 . The foundation system according to  claim 12 , wherein rotation of the head portion through the pre-cast concrete section moves the head portion and the pre-cast concrete section relative to the elongated hollow shaft. 
     
     
         15 . A method of forming a foundation for a structure comprising:
 driving at least one screw anchor into supporting ground on a foundation site; and   placing a pre-cast concrete section above the at least one screw anchor so that it is supported by the at least one screw anchor.   
     
     
         16 . The method according to  claim 15 , wherein driving the at least one screw anchor comprises driving the at least one screw anchor at a predetermined position to support portion of a pre-cast concrete slab. 
     
     
         17 . The method according to  claim 16 , wherein placing the pre-cast concrete section above the at least one screw anchor comprises placing the pre-cast concrete slab on an adapter connected to the at least one screw anchor so that the adapter is aligned with a through-hole formed in the slab. 
     
     
         18 . The method according to  claim 15 , wherein driving the at least one screw anchor comprises driving at least one screw anchor at a predetermined position to support a portion of a pre-cast grade bar foundation section. 
     
     
         19 . The method according to  claim 18 , wherein placing the pre-cast concrete section above the at least one screw anchor comprises placing the pre-cast grade bar section on the at least one screw anchor so that a head of the least one screw anchor is received in opening formed in the pre-cast grade bar section.