Repairing a roof leak on your own can save you money and time. Determine the cause of the leak, such as broken flashing or shingles, first. Repair any damaged shingles and seal the impacted areas with waterproof sealant. Temporarily cover larger leaks with a tarp to keep water out. To prevent water backup, clean out your gutters. Examine roof valleys, and reseal them if required. Wear protective clothing and use a solid ladder to ensure safety at all times. While you make arrangements for long-term maintenance, do-it-yourself repairs can safeguard your house.