Scope of Works
A scaffolding contractor needed a floating platform to build scaffold from during works to a bridge in Swansea. The bridge’s timber trestle and fendering stand directly in the river, so the platform couldn’t simply sit alongside the structure. It had to wrap around it to give scaffolders access on every side. The river wall nearby is an ancient monument, so nothing could be fixed to it. The drop from the top of the wall to the water was around three metres, the scaffold had to stay level as the water rose and fell, and the scaffold design produced high individual leg loads.
The works were planned in phases across the east, west and central sections of the bridge, and the requirement grew as the project developed. The platform started as a modest installation and was later extended to include an additional walkway and a wider footprint around the fenders.
Solution
Floating Pontoon Hire supplied double-stacked pontoon throughout, giving the extra capacity needed for the scaffold and its high leg loads. The platform was laid out in a U shape around the timber trestle and fendering, with edge protection posts fitted along the perimeter. The contractor laid ply and boards across the deck to spread the leg loads further, and small fenders protected the monument wall where the pontoon came close to it.
Mooring was the main design challenge. A pontoon held tight to a wall can end up hanging from its lines when the water drops, leaving the scaffold uneven. To avoid this we used weighted chains, each secured to a concrete block set back from the wall, passed over the edge and through an eyelet on the pontoon, then weighted below the waterline. This held the platform in place while letting it rise and fall freely.
When the scope grew from around 200m² to 450m², we reworked our crew and transport schedule at short notice. The team returned on the Thursday morning with a further 100m² of pontoon, another 150m² arrived that afternoon, and installation continued through Friday. The platform was fully installed by close of play on Friday, so the scaffolders could start their build on schedule.
