You should get your roof professionally inspected at least once a year—preferably in the spring. That said, you can perform quick visual checks whenever to catch early signs of damage. It doesn’t take much time to survey your roof and doing so can save you a great deal of money down the road. For instance, leaks can lead to myriad issues if undetected for long periods.
Walking the roof can be dangerous (even frightening for those uncomfortable with heights). Unless properly equipped, it’s best to begin your DIY inspection from the ground. Simply looking at your roof for abnormalities is often enough—colour changes, missing shingles, warped edges, etc.
Your attic will contain telltale signs of poor ventilation and leaking. Look inside for wetness and feel for draftiness. Most problems will be easier to spot if you turn off the lights. Sunlight will seep through any small holes or cracks in the roof.
When stepping into the attic, avoid walking over insulation. Compressing it will decrease its effectiveness. Plus, walking on anything but rafters may end in your foot through the ceiling below.
If you do venture onto the roof, check the integrity of your shingles first. Broken bits can affect the tightness of the flashing and gutters. Pieces of shingle can also clog the gutters, along with leaves and moss. During your inspection, make an effort to clear such debris to save later headaches.
Regarding your flashing, check all the protrusion points—skylights, chimneys, dormers, etc. Looseness here would allow water to channel underneath the roof and stream into the home. Remember to look at more than just the flashing but also what is affixing it (i.e. nails). Rustiness means weakness; the same goes for over or under-driven nails.