- 1). Climb a ladder and locate the gutters that have been installed on the side of the house. Inspect the gutters on both sides of the corner and verify they're secure to the fascia on the front of the house.
- 2). Slide the 1/2 round gutter mitre over the two pieces. Check that it fits properly and is wide enough for both of the gutters to sit in it. If not, the gutters may have to be adjusted so the mitre can reach both.
- 3). Press both of the gutters firmly into the mitre piece. Attach them to the piece with sheet metal screws. Tighten the 1/2-inch sheet metal screw through the mitre piece and into each gutter with a power drill. Space out four screws equally on each gutter.
- 4). Grip the gutters and verify they're secure in place to the mitre piece. Add more screws, if necessary, to further secure them. Move on to the next corner where two gutters need to be joined and install the gutter mitre in the exact same manner.
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