Does homeowners insurance cover a new roof?

Most likely, however, you must first determine specifically what it is you're claiming. If your roof has become a victim of simple ageing, I doubt there will be any coverage at all....unless you're paying jolly exorbitant premiums.

If it is damaged due to 'force majure' (an act of God), this may also be excluded, such as in some areas prone to tornadoes or hurricanes or cyclones. This, again, you need to check on your policy. There may be a rider for this specific purpose that you're required to purchase.

If a neighbour's tree falls across their property line and onto your roof, their home owners policy in almost every event would be covered as this is part of the liability coverage.

I'm sorry I can't address specifically as I don't know what type of policy you hold, how old it is, and what the type of claim you're considering based upon which facts.