Watertightness is effected by a built-up roofing with an exterior cladding of aluminium. The refurbishment also used an insulation foam product named Celotex RS5000, installed behind the cladding. Its front cladding has mathematical tiles. The North Stand roof was completed by adding rafters, purlins and cladding. The spiral is faced with faceted pre-cast concrete cladding panels. The fiber consists of a core surrounded by a cladding layer. It is unclear if this applies only to cladding or to insulation as well. Plate-type fuel is commonly composed of enriched uranium sandwiched between metal cladding. Police said this insulation proved "more flammable than the cladding". The outer cladding keeps this pump light confined. This material should not be used as cladding on buildings over in height. The two developments were noteworthy for their use of pre-fabricated cladding systems. Metal craft was also used in sculpturing idols, motifs, cladding and finials. Other HEAs have been produced by thermal spray, laser cladding, and electrodeposition. Materials used for cladding affect vulnerability to fire.