What’s The Best Chimney Sealant?  

Water and moisture are one of the biggest concerns for homeowners who have a fireplace. Leaking from the bricks is common as well. When it rains and snows your chimney is exposed to water. The bricks are porous and absorb water. Cold weather hits and the water that had been absorbed begins to freeze. The temperatures go up and the ice thaws. This effect can cause the expansion of the bricks. The next time it rains/snows, the freeze-and-thaw effect happens again. The pores get larger and larger. You will want to take care of it before it gets out of hand. The structural integrity may be compromised. Bricks may crack and fall out.

What Should I Be Looking For?

Cracks

Whenever you see cracked bricks, it is time to talk with a professional. Cracking may show evidence of deterioration due to the presence of water.

Spalling

Flaking bricks are a sure sign of water intrusion.

Efflorescence

A white chalky appearance to the bricks of your chimney. Moisture and water inside the bricks bring out the salt content inside the masonry. When water evaporates, crystalized salt is left behind. 

Cracks

You may also see cracked bricks from your chimney. Evidence that the bricks are deteriorating, possibly due to water invasion.

Missing or loose bricks

This is never a good sign. If you see that bricks are missing or they are loose, it’s time to call Felgemacher Masonry and Chimney. Water damage is causing this and you should be concerned. 

Mortar joints

Mortar between the bricks is also susceptible to damage from water. If cracking or flaking mortar is seen, contact a professional to repair and secure the damage. 

Types of Sealant.

When looking for a sealant it is important to know what each type is good for.

Silicone sealant

A quick-drying synthetic material. This type of sealant is good for masonry chimneys. 

Polyurethane

This is a wood sealant and would not be suggested for a chimney. 

Silane or siloxane sealers

This type works best on concrete such as masonry chimneys. 

Water-based sealants

An easy sealant to work with. It is breathable, which would work well with your chimney. 

What Is The Best Time To Seal Your Chimney?

You will want to seal your chimney during the dry summer days. It is important to wait until the weather is warmer as well. If you seal your chimney while the chimney and bricks are wet, there may be more issues. You won’t want to seal in the moisture. Waiting until you see a stretch of hot dry days would be optimal. 

When choosing a water sealant, ask the experts to help you decide what is best for your chimney. 

Call Felgemacher Masonry and Chimney at 716-907-4914 in Buffalo or 585-308-4914 in Rochester. If you prefer email us at [email protected]

A clean chimney is a safe chimney. We’ll keep yours as safe and efficient as it can be. Our owners are certified through the Chimney Safety Institute of America – a stringent industry certification. This is held by only the best sweeps in the U.S. We will remove flammable creosote from chimney flues, reducing the chance of a chimney fire.