What to do if I hired a company to replace my roof and now it’s leaking?

1) If they gave you a warranty or guaranty, you can enforce it.

2) Even without a written warranty or guaranty, they have to provide service and materials that are of commercial reasonable quality (e.g. implied warranty of fitness--the obligation that all services, products, etc. be fit for their intended purpose). If what they provided is not of commercially reasonable quality, you could sue them for compensation.

3) Similarly, if their work for negligent, or unreasonbly careless, you could sue on that basis, too.

4) If you did not pay them everything they were due, they could try to sue you for the money; you would raise the issues with the work and the damages you suffered as set offs against anything you owe them, and if the amount of damage you suffered exceeds what you owe them, you would net out positive and they would owe you money (if you had interposed your damages as an actual claim or counterclaim, not just as a defense).

5) Contractors can put liens on homes when not paid; you would need to go to court then to remove it, at which time you would also sue the contractor and subcontractor.

To sum it up: you have a right to good workmanship and to not have leaks through your roof; they have a right to be paid for their work; who gets how much depends on how the damage compares to money owed; if you can't work it out between you, you will likely end up in court with the court determining who owes who how much.