Whether homeowner's insurance covers roof leaks depends mostly on the cause of the leak and if the cause is covered by the policy. Repairing a roof can be a very costly expense, but it's a repair that can cause even more significant damage if delayed.
Normal Wear and Tear
Normal wear and tear on a roof, such as blistering or cracking of roof shingles from sun exposure, is generally not covered and will have to be repaired at the expense of the homeowner. Most insurers say it is the homeowner's responsibility to maintain the roof on their homes, and if this isn't done, the policy will not cover the cost of any damage that may result from lack of care or regular maintenance.
Regular Roof Replacement
How long a roof is expected to last under normal conditions depends on a number of factors as well. These can include the choice of materials for the shingles and the effectiveness of the ventilation.
Wind and Hail Coverage
Wind and hail damage is a big culprit in causing leaky roofs. This damage is typically covered by the homeowners insurance policy although some policies require additional riders for this type of damage. Check the "windstorm" portion of your policy in particular to see if hail damage is covered. It may also be mentioned in sections related to weather damage in general.
Depreciation of Value
The amount of money the insurer is willing to pay for a roof repair or replacement depends on myriad variables including the coverage specifics of the policy and the "value" of the roof. This is determined by the age of the roof and the assumed depreciation of value. The insurance company takes into account how old the roof is and uses that information to decide how much money it will cost to replace or repair the roof, minus the amount of depreciation from normal wear and tear that already exists.
Additional Damage From Roof Leak
If a leaky roof causes further damage within the home, like water damage in the attic, the cost of the damage repair or replacement is likely covered under the general homeowners policy, minus the deductible. The deductible amount is set by the homeowner with the original policy and determines the monetary obligation of the homeowner of each covered claim. This does not cover the cost of the repair and replacement of the roof, but rather the repair and replacement of items damaged as a result of the leaky roof.
American Insurance suggests searching for a provision within the "Wear and Tear" portion of the homeowners policy that specifies under what circumstances resulting losses will or will not be covered.
Mold From Leak
It's unlikely that any mold resulting from the roof's leak will be fully covered by your homeowners insurance policy if the insurance company deems the roof repair or replacement is not covered. Some policies have specific mold exclusions, so review your policy carefully.
Cause of the Leak Is Key
While it's unlikely that your homeowners insurance policy specifically states anything about leaky roofs, it will spell out what instances are generally covered by the policy; this is the information you need in order to figure out if the leaky roof is covered. First, ascertain what caused the leak to begin with. Was it a bad storm or a tree falling on the roof? Then, consult the policy details to see if these instances are covered.
What you think might be a leak from "an old roof" might actually be the direct result of a bad hail storm from months ago. Only a credible inspector or other professional can tell for sure. Even if you don't think the leak will be covered by your policy, it may still be a good idea to have your insurer send an inspector out to have a look as it may turn out your roof's leak is from something your policy covers.