The pre-formed insulated walls for the buildings were made from a powder coated sheeting pinned to a frame of soft wood then filled with high density foam fill. The problem was that some panels had large air blisters in them and also some ridge lines. We identified that his happens during the filling of the panel with the pressurised foam. If an air bubble gets into the panel, this subsequently expands during warm weather and the blister shows on the external skin. It will shrink to some extent but not to a degree that it is no longer visible. Also the more times the air inside expands the blister keeps getting larger. The ridge lines are caused when the foam fill is stopped and left for a period of time so it only partially sets. When you start to fill again the ridge is formed. The panels were removed and replaced as part of snagging and agreement with the client and contractor.
