If left unchecked, the moss can completely rip apart both crown and mortar joints, destroying your chimney’s structural integrity, as you can see in the images below.
The chimney will either have to be tuck pointed, or torn down and rebuilt if the damage affects the chimney’s structural integrity, as it has in the picture to the right above. Once the damage occurs to the crown, it will need to be torn off and a new crown re-laid. To prevent this from happening, call Metro Chimney to remove the moss and kill the roots once it has been removed. To keep moss from forming and destroying your chimney after this, have your chimney waterproofed with the product that we use, specifically made for chimneys, that is covered with a 10 year warranty by the manufacturer. It is also our experience that moss removal, which is necessary to stop it from destroying your chimney, also fills in the pores that are caused over time from rain water running through it and eroding them. The moss drinks up the water and once it is removed, the chimney can potentially leak after this due to the moss not being there filling in the pores to drink it up. All moss removal bids are accompanied with a chimney waterproofing bid to seal and protect your chimney from leaking it the moss was drinking up the water before we removed it. We strongly recommend any chimney that has moss removal be chimney waterproofed following it. Call us for details. See the below pictures for two examples of before and after chimney moss removal jobs.
Step Flashing is called this as it resembles a set of steps going along the side of a chimney. Metro Chimney prefers not to install step flashing as there are too many variables for it to fail, such as wind or service men on your roof pulling them up, making it ineffective, as seen below. We can install it if you want to keep up a visual continuity, but we find it far inferior in design to One Piece Flashing.