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Installing Chimney Flashing Print
Overall Skill Level: Intermediate

Installation guide for chimney flashing kit.
Steps
  1. Installing A Chimney Flashing
    1. Cut Groove in Chimney
    2. Install Top Flashing
    3. Install Bottom Flashing
    4. Install Side Flashing
    5. Chimney Flashing Kit
Tools
  • Skilsaw with a Concrete Blade
  • Caulk Gun
  • Tin Snips
Materials
  • Caulk
  • (1) Outside Closure Strip
  • (1) Inside Closure Strip
  • (1) Tube of Silicone Caulk
  • (1) Front Flashing
  • (1) Back Flashing
  • (2) Side Flashing
Installing A Chimney Flashing
Skill Level: Intermediate
  1. Cut Groove in Chimney
    Using a Skilsaw with a concrete blade, make a cut 4" up from the roof deck all the way around the chimney. The depth of the blade should be set at 3/8". You will need to check the depth periodically because as you cut the chimney you also lose blade. Failure to check the setting will allow an inconsistent depth of the cut.
  2. Install Top Flashing
    Install the top flashing first. Cut the top flashing so it extends 1" beyond both sides of the chimney. Notch the top flashing at the bends where it extends past the chimney so it may be bent around the chimney in the later steps. Make sure the top lip is in the saw cut that was made in the previous step.
  3. Install Bottom Flashing
    After the top flashing is in place, install the steel around and past the chimney. Place an inside closure strip on top of the top flashing and under the roof steel. When cutting the steel around the chimney, the steel on the sides of the chimney should be cut to allow it to be bent up and act as a natural piece of flashing. Install the front flashing with an outside closure strip underneath. The bottom flashing should be the same width as the chimney.
  4. Install Side Flashing
    Install the side flashing. Cut the ends to match the chimney lines as the trim sits on the roof pitch. The top edge will be flush with the top flashing and the bottom angle will be 1" past the edge of the chimney and bent around the front face. Caulk the 1" leg of the side flashing that sits flat on the roof steel and install. Bend the top flashing around the side flashing and caulk all seams along with the saw cut all the way around the chimney.
  5. Chimney Flashing Kit
    3' Flashing Kit6' Flashing Kit
    (1) outside closure strip(1) outside closure strip
    (1) inside closure strip(1) inside closure strip
    (1) tube of silicone caulk(1) tube of silicone caulk
    (1) 3' front flashing(1) 6' front flashing
    (1) 3' back flashing(1) 6' back flashing
    (2) 3' side flashing(2) 6' side flashing
Products, materials, techniques, tools, building codes and local regulations are subject to change; therefore, Midwest Manufacturing assumes no liability for omissions, errors or the outcome of any project. The reader must always exercise reasonable caution, follow current codes and regulations that may apply, and is urged to consult with a licensed professional before beginning any project.