Do all new homes come with a warranty or are they "as is".

Depends, but most states have some sort of law in place that says a new home, (unlived in), has to have a year warranty.

Other requirements may come from licensing agencies, condition of home builder association membership, HUD or VA if loan is financed FHA or VA, written warranty in the contract, or a separate 3rd party warranty from a warranty company. Most 3rd party warranty policies require the builder to cover everything the first year, too.

Regardless of which conditions the warranty is under, it can be hard for the homeowner to enforce it if things go wrong. Many find that home builders associations and even licensing agencies are unwilling or unable to force a builder to honor a warranty. Warranty companies do not get rich paying claims, so getting a claim paid can be hard.

Statutes of limitations on construction defects can run longer, depending on state law. This is the time limit you have, to file a lawsuit. But, because arbitration clauses in builder's and warranty co's contracts prevent suing, most people cannot sue anyway.