The Best Way to Attach Rain Gutters
- 1). Mark the high and low points and then snap a chalk line between them to indicate the slope at which the gutter will be placed. Mark the highest point of the gutter on one end of the roof, 1 1/4 inch away from the metal flashing. Mark the lower point of the gutter on the other end. You will need to lower the chalk line ½ inch for every 10 feet of run. To do this, measure the entire length of roof and divide by 10. The number you get is how many ½ inches your marking should be lowered at the other end of the run.
- 2). Attach the brackets to the metal flashing, directly into the rafter tails. To locate the rafter tails, check for the nail-heads in the flashing --- they are typically spaced 16 inches apart. Drill pilot holes in all the rafter tails and then secure the brackets to the tails using stainless steel lag screws.
- 3). Saw the sections of gutter to meet the length requirements using a hacksaw. For pieces of gutter that extend around a corner, cut that end with a 45-degree angle. If a run is particularly long, account for an 8-inch overlap between the two pieces when you cut them.
- 4). Attach any end caps to pieces that will not continue around a corner. To do this, hold the cap in place with a temporary sheet metal screw. Drill a hole that is 1/18 inch in diameter and install a pop rivet on the other side of the temporary screw. Remove the temporary screw and replace it with a second pop rivet. Seal the end cap with siliconized caulking.
- 5). Mark the location of the downspout on the lower end of the gutter and cut out the downspout hole using a hole saw attached to the drill.
- 6). Install the gutter to the side of the metal flashing by laying it into the brackets you installed previously. Drill a hole into the screw-mounting hole in each bracket --- the hole should go through the bracket and into the front edge of the gutter. Secure the gutter to the bracket using 1-inch-long stainless steel screws and flanged nuts.
- 7). Connect two lengths of gutter by placing a strip miter (a strip of aluminum) over the joint. Wrap the strip around the joint and secure it with 8 pop rivets. Waterproof the joint with siliconized caulking. The gutter is now mounted and you can connect the downspout.
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