Company Blog

How Does Extended Wet Weather Impact Your Chimney?

Many people are drawn to our overall mild weather here in SC’s Upstate Region.   However, if your home has a chimney, the rain and humidity can play havoc with its structural integrity.  In Summertime we are prone to lots of afternoon thunderstorms, and in Wintertime, we can get a frigid cold snap that is often aligned with rain, snow or ice — all of which can do “a number” your chimney.

Moisture absorption can impact the state and structure of your chimney, most notably if the water intrusion is combined with very high or very low temperatures and for an extended period of time. Common results of water intrusion in masonry or metal chimneys include:

Leaking:  

The most obvious result of excessive water absorption would be a leak.  If you hear water dripping, see water trails or have water actively dripping in your firebox, or smell musty air coming out of your chimney during warm, humid days, you may be dealing with water getting in and staying in your chimney longer than it should.  When it comes to water absorption, sooner is better than later if you want to interrupt the deterioration process that water entry often creates.

Masonry damage:

 If your chimney is brick-built or has a brick or rock veneer, water is your chimney’s worst adversary.  Water exposure can cause the bond between courses (rows of bricks) or mortar and stone to break (cracking between the brick/stone and the mortar).  It can cause bricks to crack or spall (the face of the brick pops off), or even cause bricks fall off the chimney altogether. Once damaged, brickwork becomes even more vulnerable to water intrusion.  Addressing the problem sooner rather than later can go a long way towards preventing further damage and ultimately extending the life of your chimney.

Rust:

 Rust can take place on any metal part of your chimney unless it is stainless steel or copper.  With extended exposure, rust can run rampant, if not addressed in a timely manner. Regular inspections can detect rust beginning on your chimney’s metal parts. A manufactured prefabricated chimney’s chase cover and flashing are vulnerable.  A masonry chimney’s metal cap or flashing should be monitored regularly. Also check for rust within the chimney (the damper plate) or on gas log components. Some fireboxes are metal. If water entry has been chronic, a metal firebox could be severely undermined by rust and no longer functional (safe to use).  If you think there are parts of your chimney or fireplace that are beginning to rust, a CSIA Certified Chimney Sweep can verify if your issue needs attention and can provide suggestions for resolution.

Creosote buildup:

This is one that is not commonly thought about.  Creosote is a brownish-black, sometimes tar-like substance that often builds up inside a chimney used to vent a woodburning appliance.  This buildup is worsened with increased exposure to moisture. Cold air outside of your chimney, dropping its overall temperature, creates condensation within the chimney when warm air from your fire is released through the flue.  This is worse with uninsulated and exterior chimneys. Factor in that a wet chimney is a cooler chimney and you can see how water absorption can increase creosote build-up. Similar to how your warm breath creates condensation in cold air, the hot flue air condenses and the creosote particles stick to the insides of your chimney.  Keeping the chimney as dry as possible can positively impact this process. Regular inspections will also make sure your flue is as clean as possible and will lessen the chance of a chimney fire that can result from creosote build-up.

Let our trained professionals here at Blue Sky Chimney Sweeps|Bless Your Hearth help determine overall condition, need for maintenance, issues with functionality, and even offer solutions for long-term issues.  Regular inspections/maintenance can help insure there are no issues related to moisture exposure.

Dealing with Water Damage to Your Chimney

APRIL SHOWERS BRING MAY FLOWERS…..

But before they do, your chimney might just spring a leak.  After all, a chimney is just a big sponge. Like a sponge — when it gets saturated, the water will run out anywhere and anyhow it can. Depending on how many bricks are exposed to the elements and available to soak up water, there is the potential for a great deal of water, to be managed, and with it the possibility of leaking into your home’s structure.  If it is not dealt with, over time, the chimney structure can even become compromised.

If you’d like to know more about water’s effects on masonry chimneys, please feel free to check out CSIA.ORG.

Sometimes it is obvious where the water is coming in. Given enough time, it will make its presence known.  However, more insidious water leaks often go unnoticed until there is damage and can be difficult to diagnose as to the exact entry point. Usually, there is more than one problem. A visual inspection can reveal likely possibilities and probable remedies. Sometimes where the water is being seen can indicate one or more of the four most common sources as being the most likely point of entry. In other cases, it is a trial and error process to pinpoint the source.

Most Common Points of Entry

• No chimney cap or too small chimney cap
• Cracked and porous crown wash
• Absorption through brick due to
  • Old, porous brick and/or mortar
  • Deteriorated mortar joints with voids/holes
• Deteriorated or badly installed flashing
• No cricket or saddle on the broad side of a chimney downhill from a peak

There are products and methods to address these problems.

• A full coverage chimney cap, preferably with a lid (with drip edge) that overhangs the sides of the chimney, can prevent rain from entering the flue and provide added protection for crown wash.**
• An elastomeric coating can seal the crown wash or a cast and poured crown with a drip edge can be created. Either option helps prevent water from freely soaking in from the top.
• A breathable water repellant and/or crack sealer designed for chimneys applied to the brick and mortar can prevent water from soaking in from the sides.
• Deteriorated mortar joints can be tuck-pointed.  Holed can be filled.
• Complete rebuild may be necessary if an aging chimney is too deteriorated to repair.
• Metal flashing can be repaired or replaced; or a flexible, surface bonded flashing can be applied to correct improper or deteriorated flashing.
• A cricket can be added to the roof at the base of a chimney where water tends to puddle during heavy rains.

How do you know if it’s the chimney or the roof?

One way is to wrap the chimney with plastic and wait for rain.   No sign of water even though it rains, says it’s probably the chimney.   If you still see water with the rains when the chimney is wrapped, the leak is probably in the roof uphill from the chimney and water is running down to the chimney.

**More information from Blue Sky Chimney Sweeps|Bless Your Hearth about chimney caps can be seen on this website at  Chimney Caps & Animal Guards  or  Two-for-One