Solaglas manufactured and installed Skyline Central's glass tower

West Properties’ Skyline Central development in Manchester city centre is the epitome of luxury living. Offering high-spec one and two-bedroomed apartments and a rooftop leisure suite with a 20m jet black swimming pool, steam room, jacuzzi, spa, zen lounge and gym, it raises the bar in terms of city living.

Externally, Skyline Central doesn’t seem to dramatically deviate from a standard apartment block design, until you cast your eyes skyward and catch a glimpse of the six storey glass tower overhanging the street below by a whopping 4.2m.

The glass structure is the brainchild of Solaglas Structural Contracting – a striking and workable interpretation of architect Jacobs Webber’s ‘protruding glass shard’.

Having no real sense of how the glass structure would translate in practical terms, as this was an industry first, a general enquiry was sent out to gain a perspective on its achievement. Four companies responded by flatly claiming that it couldn’t be done whilst only two tentatively agreed to look at it in principle. One of these being Solaglas.

Solaglas eventually won the tender on the strength of its enthusiasm, expertise, detailed knowledge of the intricacies of how buildings work and the fact that the company had a few advance drawings and details that its competitor had failed to deliver. Solaglas had also taken the time to address access issues prior to commencing the work which had further impressed the developer.

Once the contract had been won, Solaglas set about designing the 11 tonne steel structure that would house the glass for the six-storey tower. The seven month design process highlighted problems with constructing the frame at the top of the building, so to reduce the amount of man hours working at height the decision was made to assemble the steel frame at ground level on an adjacent public car park which Solaglas had to hire for the duration of the build.

This proved to be a major operation as the company had calculated that, once stood upright, the structure would be over 21m tall, unstable, and incredibly top-heavy due to one side of it being sloped. Solaglas therefore decided to build the structure on its side incorporating a temporary leg for stability, which meant at full height it would only total 6m.

After the steel structure had been completed on-site, it was time to crane it into position and attach it to the building. A specialist 500 tonne crane was used to lift the frame into the vertical axis and the temporary leg was removed. The crane then had to lift 11 tonnes of steel above Manchester’s busy Rochdale Road and be aligned with the studs that were in place on the concrete slab it was designed to rest on. It was a tense moment for business manager John Harvey and his team as they watched the structure ascend but thanks to the time and effort allocated in the initial stages of the project the entire lift and placement took no longer than an hour.

John Harvey explains: “We had positioned the studs and base plates in exactly the right position on the structure and the slab, so we had done the calculation homework before putting it into practice. From the moment they started to lift to the moment it was fitted in its final position was, I’ll bet, no more than an hour. And I said to everybody, ‘why have I just spent £35,000 making sure everything’s right for it to just take an hour?!’ and they said ‘that’s why it only took an hour!”

With the steel structure firmly in place the next hurdle was to glaze it. The concept of glazing the structure on the ground and lifting the entire unit into place had been considered, but there was a very real possibility that the lift would not go as planned as the glass may have broken by the steel frame twisting during the lifting process, so the idea was quickly quashed.

The other option was to glaze the structure in-situ, 220ft above one of Manchester’s busiest roads. To ensure the safety of both those working at height and the pedestrians on the ground, Solaglas had to make sure all angles were covered. John Harvey continues: “We had netting around the building to stop anybody falling off, or anything falling to the ground, which would have stopped most things. But if a piece of glass fell off there was some debate as to whether it would stop it, so we put fully cantilevered scaffolding around the steel structure which meant that each level of the glass installation would have to be 100% complete before the scaffold could
be dismantled in a ‘top to bottom’ manner. A Health & Safety manager was present at all times to carry out in-depth safety briefings with the entire team, ensuring safe working methods were implemented at every stage and any safety concerns were addressed immediately. Clothing co-ordination was essential for people to be aware of one another’s job functions.”

By the time it came to glazing the structure winter had well and truly set in which made it difficult for the company to work at the pace it had hoped. Being unable to glaze in the rain or at wind speeds greater than 25mph meant that some days only two-to-three panes were being installed. This, coupled with the fact that Manchester City Council had insisted the crane be removed by the first week in December 2006 to make way for Christmas shoppers, meant going into overdrive, working double shifts and night shifts to meet the deadline.

Luckily the job of attaching the 500kg double glazed units to the sloped side of the steel frame was made easier by using a bespoke, remotely operated counter balance beam and vacuum glass lifter designed by project manager Ian Harvey. This made it possible to install the glass at the precise angle of the slope and beneath a 4m under-hang.

So, with the pressure on to finish the job, the tower was slowly but surely beginning to take shape. With a week and a half to completion and only the last two levels to glaze, disaster struck. A key pane destined for the lower section of the sloped area had broken during one of the lifts. The company couldn’t account for any breakages by ordering ‘spare’ units as they were all different shapes and sizes so it had to act fast. The lead time on the delivery of a new piece of glass from Austria was a standard eight weeks but with completion due in just over one week, Solaglas had to think outside of the box...quickly!

John Harvey continues: “I made one call to a lunatic... my father! I told him to meet me in Manchester in 3-4 hours and that he’d need the van, the Sat Nav and an overnight bag for about five nights! While we waited for him to arrive, the broken side of the double glazed unit was cleaned off ready to go on the side of the van. He then set off on the 26 hour journey to Austria. In the meantime, we make a call to Austria and order two new panes just to be on the safe side. Dad arrives, has the glass fitted into the unit, waits for it to go off and then embarks on the return leg of the trip. The total operation took eight days, which was much better than delaying the job for at least eight weeks!”

Whilst Mr Harvey Senior was saving the day in Austria, the company pushed on with glazing the last two storeys, taking the scaffold down as they went until eventually they were left with just the one gap to fill. Because the scaffold was now completely dismantled and the crane had been removed to make way for Christmas shoppers it meant the last pane had to be fitted using the balance beam, mobile crane and a 75m, lorry-mounted access platform.

Solaglas had managed to convince Manchester City Council to give them three hours to get the pane into position. The wind was a real factor that day and the operation made for uncomfortable viewing 70m above the ground but once again, due to careful planning and meticulous calculation the pane was guided in by the installers externally from the access platform and internally from a scaffold tower with no problems.

With the glass tower now complete it was painted off, cleaned out and the internal scaffold was removed. This just left one final point to negotiate... the project value....

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