This chimney previously vented an improperly installed wood stove insert that is responsible for the staining around the top and down the side of the chimney. These creosote stains are nearly impossible to remove.
The chimney has the typical construction defects that lead to water damage. The mortar wash is porous and cracked. The top course of brick is stepped in, creating a ledge that collects water.
Plastic sheeting makes a bond break between the chimney structure and the concrete. This isolates the crown from the differential expansion and contraction of the chimney structure. The first bucket of concrete is placed around the form to hold the edges of the plastic in place.
The crown forms are removed and the concrete is coated with acrylic sealer. The acrylic sealer holds moisture in the concrete and allows it to cure over a longer period of time.
Pressure washing has cleaned up the chimney considerably, although some of the staining remains. The new crown is complete and will protect the chimney from water penetration. ChimneySaver Water Repellent has been applied to the chimney exterior.
Of all the common defects we see in chimneys, improper termination is the one that will most assuredly damage the chimney structure over time. Masonry structures are susceptible to damage from water penetration. The chimney in particular is not protected from water by the roof. The chimney stands above the roof, exposed to the ravages of the weather from all sides.
If the chimney is not built properly to withstand the forces of nature pitted against it, it will deteriorate quickly. Early correction of water penetration problems can greatly extend the life of the chimney structure.
We just finished correcting some of these typical defects today.
