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Hanging the Needle Beams So that we wouldn’t have to wrestle with heavy beams high in the air, we hung the needles from the garage ceiling, perpendicular to the joists. We drilled through from the apartment floor above and used all-thread to snug them in place. We used a transit, stringlines, and plumb bobs to keep track of the building’s lateral movement as it was lifted. We also ran strings along the bottoms of the needle beams to ensure that we lifted the building uniformly. While the building was raised, we excavated a trench for new footings, including jackhammering out the old concrete (Figure 5).

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Figure 5. While the second story of the carriage house was suspended, the crew excavated, formed, and poured new footings (top), then repaired the wall framing and lowered the building onto new PT sills.

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We formed and poured a reinforced perimeter footing, with rebar pins sticking out on the inside to tie into the new slab. We poured the new slab on top of the old; its final elevation was 12 inches higher than the original slab. The extra precautions we took setting up the job meant there were no problems later. Just to be on the safe side, though, I did increase my liability insurance. Because of the height and the extra measures involved, the carriage house job cost three to four times as much as it would have for a similar-sized building on the ground.