| 摘要 |
A second story addition is provided on a pre-existing residence by severing straps connecting trusses of a first portion of the original roof of the structure covering a first section of the residence on which the second story room is to be added. The first roof section also is severed from the remaining portion of the roof. Roof lifting brackets are temporarily installed under the truss chords to support all of the trusses and are engaged by eyelet bolts which extend through the top of the first roof section. Cables support by a large crane are attached to the eyelet bolts, and the crane lifts the first roof section, including a ceiling attached to the bottom of its trusses, from the first section of the residence and sets the first roof section on the ground. Cables supported by the crane then engage eyelet bolts attached to a pre-constructed floor section. The crane lifts the floor section, aligns it with the first section of the residence, and sets it thereon. The crane is then operated to position pre-constructed wall sections on the installed floor section. The crane then lifts the first roof and places it on the installed wall sections.
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