That's just talking about the spire. As for the rest of it, the bill includes the language "If the [conservation team] uses materials different from those in p

That's just talking about the spire. As for the rest of it, the bill includes the language "If the [conservation team] uses materials different from those in place prior to the disaster, it [should] publish a study giving the reasons for these changes." Seems to me like "We're using steel instead of wood for non-visible parts for reason of it not being flammable", that would be a good reason.