It's not so much the difference between aluminium and zinc but the selection of the cheaper of the two available aluminium ones with the poorer fire rating. The difference there was about £5k IIRC.
However there's still the issue of the insulation's fire resistance that's not even beeing tested at the moment and the tests that are being done are on the individual components of the aluminium cladding not the composite installed as intended. An interviewee on R4 Today programme this morning asserted that all the current testing was a waste of time and effort.
A bit like testing a lump of wood for flamability and then condemning all timber-framed properties when it catches fire.
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History is much like an endless waltz: The three beats of war, peace and revolution continue on forever.
However history will change with my coronation - Mariemaia Khushrenada
