The purpose of gutters is to to collect rainwater from the roof, and channel it down and away from the house. If gutters are neglected and fall into disrepair, rain water will seep into your foundations and eventually, into your home.
Damaged gutters, hangers, downspouts, and bottom troughs need to be replaced immediately.
All gutters should be cleaned at least twice a year. If your home is in the shadow of needle-bearing coniferous trees, you may have to clean the gutter more often. If gutters are not maintained, needles can gather quickly and even clog your downspouts.
Gutters are easier to clean if the refuse is slightly wet, so choose a damp day to do the job. Lean your ladder against the house, never against the gutter. Move it as often as necessary so you do not have to lean. After you have cleaned our all the refuse that you can, use a garden hose to flush the remains down the nearest downspout.
As the water is flushing, take note of any areas where your gutters leak, this includes in the trough that takes the water away from your home, as well as any areas along the gutters where the water is pooling.
If water is pooling you will have to realign the gutter by bending the nearest hanger, or by adding another hanger. All gutter should slope very slightly towards the nearest downspout. If your gutters are seriously misaligned, you may have to remove a whole section and start from scratch. To check that your gutters slope perfectly, use a large marble and watch how it rolls. If it stops, that is an area that needs attention.
Leaking gutter joints may be a result of faulty alignment. If any joints still leak after realigning, use a synthetic rubber sealant and caulk the joint.
In older homes, there may actually be holes in the gutters. If these are small, clean the area thoroughly and apply a small patch of a similar metal and sealant. If the hole is in an area where the metal is shiny, fix the patch to the inside of the gutter, using an epoxy or resin. Paint as needed.
If you maintain your gutters and make small repairs as needed, your gutter system will last for many years. On the other hand, if you gutters are leaking badly and large holes are appearing, it is probably time to replace the whole system.
A word of caution. Every year thousands of people are hurt when falling from ladders. Many die. Take the time to position your ladder directly in front of the area you are attending. To avoid reaching and losing your balance, move the ladder often.