Q&A: During a recent storm, a branch from my neighbor's tree fell onto my roof. Who's responsible for the repairs and cleanup?

Unfortunately for roofs everywhere (not to mention shiny new sedans in driveways), this is an all-too-common query. In the September 2008 issue of Consumer Reports, we report that trees are among the most common causes of neighbor disputes. Couple that with the extreme weather now gripping the nation, and that's a lot of fallen tree limbs setting off some serious border wars.

So who has to pony up for the damages? The answer—as it often is where the law's concerned—is, that depends. If your neighbor knew, or should have known, that the branch was unsound, he or she is guilty of negligence and is thus responsible.

But unless the neighbor is a forest ranger or tree surgeon, proving negligence can be tricky. You might argue in court that the lack of foliage or visibly diseased bark provides clear proof that the limb in question was unsound. But the judge may not hear that defense, which is why neighbor disputes are best resolved outside the courts.

"You don't control the outcome," says Jonathan Rosenthal, executive director of Alternative Dispute Resolution Programs for the District Court of Maryland. "It's entirely up to the judge, who may only listen to certain evidence." Rosenthal (like everyone we interviewed for the September report) recommends mediation, in which a neutral third party helps feuding neighbors figure out a fair solution.                

But back to the tree branch on your roof. Culpability aside, most homeowners' insurance policies cover damage done by a neighbor's tree. After compensating you, the company may turn around and sue your neighbor, but you'll be spared the legal fees and inconvenience. However, the incident will almost certainly sour neighbor relations.

That's why it's best to address unsound limbs before they come hurtling to the ground. Any large or old trees should be inspected annually. Note that you're within your right to cut back from a neighbor's tree branches that encroach onto your property. As a courtesy, tell your neighbor beforehand. With any luck, the neighbor will share the expense, which can run anywhere from $300 to $1,000—still less than the cost of a new roof or car.—Daniel DiClerico

Essential information: Read our latest report on homeowners' insurance, which includes five ways to cut your premiums. And bookmark our Storm and Emergency guide ahead of the next major weather event.