James Paget University Hospitals NHS Foundation Trust in Gorleston is just one example of how innovation, borne out of its vertically integrated supply chain, could emerge as a blueprint that could be used on other sites around the UK.
They have utilised a solution that will keep these RAAC planks safely, swiftly and securely propped for years to come. The solution started with locking down three key pillars for success:
1. A structurally sound and tested solution2. Quick and flexible installation process3. Best value for money
Whilst the obvious structural support solution would seem to be steel, when the team checked the method against the three deliverables, it fell largely short of points two and three.
The main challenge with steel reinforcement is that each RAAC plank would need to be surveyed by the fabricator (for which access to the areas would be needed), after which a lengthy programme around the steel lead time would need to be implemented so that delivery would be on an agreed date when the area could be accessed for installation.
Given that the RAAC planks are in live wards, and even theatres, arranging access for set-in-stone dates is immensely challenging – the steel solution unfortunately fell short on the quick and flexible installation process pillar, whilst material shortages and cost increases also meant it was not meeting the best value for money criteria.
Working with the Estates Department at the James Paget University Hospitals NHS Foundation Trust, Morgan Sindall Construction, Frank Shaw Associates and WSP took the solution right back to the drawing board to challenge what they thought they knew, with the art of the possible.
After individually scanning each plank to locate steel reinforcement, setting out in accordance with the Structural Engineer’s design criteria and utilising a vacuum plate drill, holes are drilled through the existing downstand beam.
New timber beams are cut to length, lifted into position either side of the existing downstand beam, and drilled to align perfectly with those drilled previously. 16mm stainless steel Hilti threaded rod is inserted, with washers, and nuts attached. Domed-head nuts are fitted, and the timber decorated where visible.
In areas where existing services and obstructions prevent though bolts, Hilti studs are used to an amended Structural Engineer’s specification.
The timber method provides necessary flexibility, whereas the steel method does not. For an enhanced structural solution, such as where the entire plank needs to be supported, our timber method works equally well, with joist hangers. Plank deflection can also be easily accommodated in timber.
In areas where enhanced structural solutions are required, timber ladders are also placed in-between the timber beams to further reinforce, and finally the beams are painted white to seamlessly match in with the roofing.
Further development utilises Unistrut framing suspended from the timber beams to support services and ceilings. Thereby removing these existing loadings from the roof.
We have further developed the Unistrut frame to conceal sections within walls where occupant restrictions require. 90% of works, can typically be completed in 2 days. with the finished element requiring no unsightly or intrusive propping - and estimated 70% faster than a steel alternative.
Pictured: close up image oftimber support bolted and painted
Programme-wise, when you look at one of our theatres, along with its recovery area that we had freed up for the work for example, there simply wouldn’t have been enough time if we had undertaken the work in steel. But with the timber solution, we were able to programme refurbishment work, and the RAAC planking work to be undertaken concurrently. It’s given us a quicker, easier and more cost-effective solution, and it looks better as well.”
The team has also ensured the solution can even deliver full plank support. Pictured here at James Paget you can see the timber support spanning in-between the steels as support, with more timbers supporting right across the planks at 90 degrees. Once bolted securely and painted (with 9mm ply used to bridge any spoils in the planks), the system produces unrivalled structural support in these areas.
