Tree-mendous! How did they get that tree in there?

If you want to plant a 1.3 tonne tree in a giant pot that is up a flight of steps, through three double doors, and across a courtyard that has a low weight load suspended floor who are you going to call?

That was the challenge facing a leading corporate plant provider when it was commissioned to create the planting for a new office block in Dorking, Surrey – and it called lifting specialist Hird Group.

Free site survey supports crane lift

Hird Lifting Depot Manager James Carr said: “As part of our service, we offer a free site survey. This helps both our clients and us, as a lifting equipment hire provider. In this case, it allowed us to provide precisely the right equipment, and propose an effective and safe lift plan.

“We had to break down the lift into the different tasks, starting with getting the tree off the lorry, and finishing with it in its pot, looking glorious.

“Along the way, a careful assessment of the risks, and the methodology for mitigating them, helped us get the job safely done in half a day. That meant our client’s costs were controlled and disruption was minimal.”

Two mini cranes – one crane operator

The office owner had wanted an impressive feature tree to create just the right look and feel in the courtyard at the centre of the new building.

The answer was to use two tracked spider cranes – a UNIC 506 and a Maeda MC285, controlled by a Hird crane operator. They completed different lifting tasks needed to get the tree into its pot.

First, the UNIC 506 spider crane, which has a maximum safe working load (SWL) of 3 tonnes, was used to lift the tree from the lorry up on to the main entrance level above a flight of steps.

It then lifted the Maeda MC285 spider crane up to the same level. The tree was taken through to the court yard some 20 metres away through the building on three pallet trucks.

Narrow spider crane essential

The Maeda MC285 spider crane was then driven through to the lift location by the same route. At only 750mm wide with outriggers stowed, it could quite easily be guided through three double doors.

The next challenge was to set up the mini crane for a safe lift. The courtyard had a suspended stone tile floor which would not take the weight of the crane while lifting the tree.

James Carr, who was the Appointed Person for the lift, said: “Our solution was to lay plywood to spread the load of the crane and protect flooring in the building and in the courtyard.

“We then lifted out floor tiles at the points where the outriggers needed to be placed. We also put down outrigger pads to spread the load and ensure a secure footing for the lift.

“The weight of the load, and the position of the pot it was being lifted into meant the spider crane had to be positioned precisely, with the lift radius staying within the area of the two front outriggers.”

Impressive spider crane – impressive tree

With these technical constraints fully accounted for, the lift went ahead smoothly and safely. The tree was placed in its pot, under the client’s guidance, and looked just as impressive as was hoped.

The Maeda MC285 spider crane (maximum SWL 2.82T) could then be derigged and driven back to the main entrance, where the UNIC 506 mini crane could be used to lift it back down to street level.

James Carr said: “Our experience, and the mini cranes and lifting equipment we can deploy, make these confined space lifts feasible. Leaving people to wonder for years to come: ‘How DID they get that tree in here?’”