How to Clean and Repair Gutters
First, climb a ladder and clean the goop out of the gutters. Pay particular attention to the downspout. If leaves and debris are clogging it, water won't drain properly, and along with mildew and mud, you'll end up with sagging gutters. Tip: The decomposed leaves make great mulch or compost.
Check Gutter Spikes
Check all the spikes that are supposed to go through the gutter, through the fascia board and into the rafter behind it. It's a good idea to invest in new gutter spikes so the gutters are securely fastened once again.
Check for Leaks
Check the sources of any leaks, including holes in the gutters and cracked caulking in the seams. Use an old chisel to scrape the old caulking out and dry the area thoroughly. Use new bead silicon sealing to keep water from getting behind the gutters and rotting the boards.
During this inspection, check out the rivets on the downspout. Frequently they'll be loose or will have dropped out completely. You can use a rivet gun to secure them anew. Tip: Purchase new rivets at a local hardware store. You can also buy a rivet gun there.
Clean Gutters With Pressure Washer
Once you've finished with the mechanics, begin cleaning the gutters. The best way to do this is with a pressure washer. Follow the pressure washer instructions to a T. A pressure washer won't hurt the gutters provided you've secured the gutters with screws or new spikes. The real key is to avoid hitting the gutters at too high an angle or you'll blow the shingles off with a high-pressure stream of water. Tip: You can rent a pressure washer for less than $100 at most places if you don't plan on using it often.
If the gutters are rusting, you might want to consider new gutters. But if you're going to stay with the old ones, get all the rust off, sand them down, paint them with a good primer and then with a good-quality rust-inhibiting paint.
Remove the old gutter spikes and ferrules (the large spacers that keep the gutter walls from collapsing while you drill), installing each new set as soon as you remove the old one.
Position the new ferrule inside the gutter, directly behind the existing spike hole.
Insert the gutter screw into the existing spike hole. Use a standard variable-speed drill, electric or cordless, to slowly thread the fastener through the spike hole and the ferrule and then into the existing fascia hole.
Thread the fastener until the head is even with the gutter and the screw has engaged with the rafters on the other side of the fascia board.