There are several instances in which it might make sense to file a claim against your neighbor's homeowner's insurance company. If your home was damaged by a structural component of his or her house, you might have reason to suspect that his or her negligence caused the problem. If a tree limb or other natural feature that originated on his or her property caused structural damage to your home or outbuildings, you might believe in the merits of such a claim as well. Likewise, you might expect your neighbor's homeowner's insurance provider to pay for the damage that the roots of one of his or her trees caused to your plumbing or sewer system.
Unfortunately, you're legally prohibited from filing a claim against your neighbor's homeowner's insurance company. Regardless of the apparent merits of your case, such a claim simply isn't permitted in any legal jurisdiction. If you have your own homeowner's insurance coverage, you'll need to file a claim with your provider. If you don't have homeowner's insurance, it's unlikely that you'll be able to recover any money from your neighbor's homeowner's insurance provider.
However, it might be worthwhile for you to attempt to make such a recovery. You'll have just one realistic option for doing so. This will involve filing a formal lawsuit against your neighbor. If you suspect that he or she doesn't have the resources to pay for the damage to your home, you'll need to file a suit against his or her homeowner's insurance provider as well. In either case, the provider will ultimately pay for the damages: If your neighbor is found to be liable, his or her provider will reimburse him for the full amount of your award. As such, you shouldn't feel bad about filing the suit.
Once you file your lawsuit, you'll need to prove that the damage to your home or property was the direct result of your neighbor's negligence. This is liable to be difficult: Unless you can convince your neighbor to testify in frank terms about his or her supposed negligence, you probably won't be able to build a convincing case. Since your lawsuit won't be a criminal matter, you won't be able to subpoena any maintenance records. In fact, your only option may be to present the testimony of a third-party appraiser or damage expert. Unfortunately, your neighbor's homeowner's insurance company will be free to refute such testimony with the opinions of its own appraisers.