[towerguy3]

In Toronto how did they take the overhead cranes off the tallest towers there such as First Canadian Place, Scotia, BCE and TD towers; the ones over 600 feet high?

Did they take the final assemblies off with helicopters or lower pieces down with a derrick crane, disassemble the derrick and carry those pieces down in the tower's elevators?

I would assume considering the close proximity of adjacent towers and the risk of the helicopter crashing, the insurance for a helicopter lift in the downtown core could make the whole effort cost prohibitive?

[itsbryan]

That's a good question. I would imagine they take it down piece by piece and then lower the parts off of a winch/pulley system from the side, onto a truck below.

I've also heard of contractors building smaller cranes onto the foundation and then lowering larger pieces down.

[asher11]

I believe the big crane brings up a smaller crane which lowers the pieces of the big crane down. Then they have an even smaller one that lowers the parts of the 2nd crane down. This smallest crane is then dismantled and lowered down either through the elevator shafts or maybe just over the side of the building. This is how they did it on the ROCP towers.