Chimney Repair and Seal – list of what to look for – Video

Repairing or Sealing a Chimney Crown

Watch the video for tips on what to look for to seal or repair a chimney. Most chimneys need some maintenance over the years. The flashing comes loose, or the grouting starts breaking out. Most roof leaks are due to a lack of chimney maintenance.

To use the incorrect chimney sealant could become very costly. Silicone spray-on stuff does not work and also caulking is not the way to seal a chimney. In most cases caulking a chimney will cause problems and caulking hs to be removed before a proper repair can be made.

There are Four primary areas to check on a chimney that can cause leaks.

• The crown – That’s the cement slab at the top of the chimney. After many years the slab cracks and water leak inside the chimney causing the water to freeze during winter. The ice will crack the chimney or bricks.
• The face – That’s the brick or stone part of the chimney. Many times the grouting has cracked, or the stone is coming loose due to the crown that was letting.
• Flashing – This is by far the number one cause of leaks on any roof. Flashing is for the most part made from metal. The metal flashing is inserted into a slot cut into the chimney. The cement grout does not bond to the metal and therefore causing leaks.
• Stucco or Siding – Almost always one can find cracks when a chimney is covered with stucco.

Cement slab on top of the chimney

Notice the cement slab pulling away from the brick. The crack will allow water in and during winter freezes up causing the grout to crack further.

Flashing on a chimney

The next part to inspect is the flashing on a chimney. It is almost a guarantee that you will find that the flashing causes the leak. Tis happens when the grouting that is suppose to hold the flashing in position, has come loose and is no longer a seal.

Stucco Chimney

The chimney below is an example of a repair that has gone bad. This used to be a brick chimney and then someone tried to fix it by putting a cement layer over it. Putting cement to seal the brick is not a bad idea, but the very top of the chimney was not properly sealed and water leaking in causing the cement to crumble.

At the bottom of tis shimney is no flashing either. They did the stucco layer but never added the necessary metal flashing to make the transition to the roof. Notice the tar that is smeared at the base of the chimney to tie the roof in.

When cracks develop on a chimney, the water seeping in from the cracks will compromise the integrity of the rest of the structure. It is best practice to have the chimney inspected every 5 years to make sure all cracks are sealed.