How to Correct Poor Roof Design to Stop Chimney Wood Rotting
Often times problems with roof leaks around chimneys are because of water pooling on the rear side of the chimney. The slope of a roof comes down to the rear of the chimney causing water to collect there. This pool of water will leak through the roofing materials and wet the deck just underneath it.
What You'll Need:
- Shingles that match the existing roof
- Plywood
- 15-pound tar paper
- 2 by 4 boards
- Saw
- Level
- Roofing nails
- 16d nails
- Hammer
- Chalk line
- Use measuring tape to measure the exact distance from the chimney to the roof that is behind it. Cut a 2 by 4 that is equal to that length. You’ll need to make an angle cut that will allow the 2 by 4 to sit flush on the roof. Put the 2 by 4 onto the rear of the chimney as well as the roof. Ensure that it is level. Ask someone to assist you and measure the distance from the base of the chimney to the bottom of the horizontal board, cut a 2 by 4 to equal this length.
- Nail the horizontal 2 by 4 onto the vertical 2 by 4. You’ll need to nail the horizontal 2 by 4 onto the using 16d nails. Use a level to ensure that the horizontal board is level and you’ll also want to ensure that the vertical board is flush and level against the chimney.
- Use measuring tape to measure the distance from the top of the horizontal board all the way to the outer base of the chimney where it meets the roof. Cut a 2 by 4 to equal this length. Ensure that you are able to cut each end so that it is flush to the horizontal board and the roof. Use 16d nails to nail the board. Repeat this process for the opposite side.
- Run a line of chalk starting from the base of the first rib on one side all the way back to the roof end of the horizontal board then pop the chalk line. You’ll need to repeat this process for the opposite side.
- Locate the middle of the chalk line on both sides. You’ll need to find the measurement from the middle line to the middle of the horizontal board and cut a 2 by 4 that is equal to this measurement. Cut both ends so that they meet flush to the roof as well as the board. Use 16d nails to nail the board in place. Repeat this process for the opposite side as well.