The Rev. John Woodford says 70-year-old Gerald Dean Wacker, of Walthill, Neb., was helping to build the garage for Good News Baptist Church when he fell Tuesday.
Woodford says he did not see the accident, which happened about 1 p.m. Tuesday, and did not know exactly how it occurred.
Wacker was taken to a Sioux City hospital, where he later died.
Woodford said Wacker was a generous and humble man who was quick to offer help to others.
A funeral service is set for 11 a.m. Saturday at the church.