![](https://constructionmanagement.co.uk/wp-content/uploads/2020/04/How_we_fixed_it-4.jpg)
Gavin Ellis, MD of safe access specialist Eurosafe Solutions
What was the problem?
This 104m high government building is home to the Netherlands’ Ministry of Health, Welfare and Sport and is one of the tallest in The Hague, resembling a tower block capped by two very steeply-pitched triangular roofs. The metal composite roofs were leaking so badly that a new roof structure had to be built on top to make them watertight, but at 21 storeys up erecting scaffolding from the ground would have cost hundreds of thousands of pounds, and use of a cherry picker was impossible.
What was your approach?
We used rope access techniques to patch repair the roof, install a layer of insulation and a Kalzip aluminium skin, then build a permanent abseil system on the roof ridges designed to allow permanent, long-term access for maintenance.
The Dutch contractor, JP van Eesteren, filled the V-shaped gap between the roofs with scaffolding, which gave us a flat surface to store materials and abseil from to reach the outside surfaces.
The permanent access system is accessed via the flat lower roof located between the two pitched roofs. A specially-adapted electronic climbing trolley, typically used for window cleaning cradle systems, climbs a 25m-long rail up to the ridge line from which trained abseilers can attached their ropes.
What was the biggest challenge?
This was the first time rope access had been used on such a tall building in Holland, so the Dutch were very stringent on safety and we were asked a lot of questions. The Castalia’s roof is also very bespoke and our team had to undergo a four-day training course to become approved Kalzip installers.
Couldn’t the Dutch have done the abseiling?
Operatives could have undergone a five-day rope access training course, but they still would have needed a trained supervisor, which requires around three years’ training.