By what means can a warranty be devised to survive the collapse of the
company (liquidation, voluntary or otherwise); and by what may I
recognize them as existing?
Some companies outsource their warranties to a third-party warranty provider that either by virtue of the nature of their business, or insurance industry regulations, is more likely to continue to exist than a construction company.
Construction companies also often assign warranties from the manufacturer that come with the installed items in the building to the end purchaser of the building, and manufacturing companies tend to stay in business longer than construction companies.
Keep in mind, however, that many long term warranties, or "lifetime warranties" are written so that they only cover defects that arise from the condition of the warrantied thing at the time it was sold, even if it took a long time to be discovered or to manifest. This is increasingly hard to prove as the years pass from the original sale.
Of course, there are no absolute guarantees in life. To some extent, one has to guess how long there will be someone to honor it (and how long the owner of the property and the successors to that owner will be able to keep track of their warranty related records).
