Our Company Blog

Basics of Chimney Flues and Flue Sealant

The flue system is a combination of many parts that work together to vent a fire. In order to do the job correctly, the parts should be installed correctly and maintained regularly. This means that homeowners should schedule routine chimney sweeps, and annual inspections to have the safest and most efficient chimney system.

The Flue

The flue is the actual vent that the byproducts from the fire flow through. It goes from the fireplace to the top of the chimney where it’s protected by a chimney cap. The flue should be lined with a flue liner that protects the masonry from corrosion, protects the home from hazardous gases, and prevents heat transfer. The flue liner’s surface should be smooth, and joints should be strengthened with a high heat sealant.

HeatShield® Cerfractory® Flue Sealant

Cerfractory® technology is a hybrid ceramic/refractory material, developed over 20 years ago. It’s a combination of high-fired ceramic with the heat resistance of high-temperature refractory cement. The sealant is a powder, that is mixed with water right before use. This sealant should be applied only by a qualified professional. Once mixed and applied correctly, it air cures to a hard, ceramic material that is moisture resistant, and corrosion resistant. This smooth surface keeps its strength and shape despite high temperatures and chemical abuse.

HeatShield® Repair Systems

At Chief Chimney Services, we know the importance of an appropriate flue liner and offer services to keep your flue working for you. We use HeatShield® Cerfractory® systems for chimney restoration, joint repair, resurfacing, and relining.

• Joint Repair System – For chimneys with defective mortar joints, to repair and strength mortar joints to restore the flue to full function. The sealant is applied with a special applicator that fills cracks, gaps, and voids, smoothing the surface as it goes.
• Resurfacing System – To repair mortar joints and minor defects in tile lined flues, specifically. The sealant fills gaps, cracks, strengthens, and smooths surfaces. The resurfacing system covers the entire flue interior from top to bottom, restoring a damaged flue that is structurally sound.
• CeCure® Sleeve Relining System – To restore the chimney liner when serious defects are present, or to line an unlined chimney. HeatShield® is used in combination with a liner sleeve and then sealed with the sealant, for a smooth surface for the interior. The technician checks the work with a video surveillance system.

Call Now

When your flue is damaged, dirty, or inappropriate for your fuel type, you should get it looked at as soon as possible. If your flue isn’t working properly, neither will your chimney system. Voids, gaps, and cracks in the liner or flue will lead to water damage in the chimney, hazardous gases in the home, inefficient chimney, and increased fire risk. Just as it’s important to have a professional sweep and inspect your system regularly, it’s important to have a professional apply a sealant. An amateur may use sealants that aren’t appropriate for high heat. When you trust Chief Chimney Services to repair your flue, you know we’re putting your safety and comfort first.

Call Chief Chimney Services today and talk to a flue expert about flue sealant.

The Function Of A Chimney Cap

Did summer storms dislodge your cap? Maybe you’re not convinced it was installed correctly in the first place, or you’re unimpressed with it’s design and function. If you had a chimney cap installed, but your fire is affected by wind gusts, wildlife, or it’s allowing rainwater into your chimney, you need a new cap!

Protection from the Top-Down

The chimney cap is often overlooked, especially by older generations, but it has never been more important. Chimneys are constructed to withstand time and chemical abuse, but they can be destroyed on the inside, from outside influences.

Chimney Caps Keep Water Out

Rain, sleet, snow, and wind can affect your chimney. Without a cap, precipitation falls directly into the flue, and begins affecting the chimney system right away. Water penetration is the worst thing that can happen to your masonry chimney. Masonry is constructed of many different materials, and all of them are adversely affected by water. Water in the chimney can cause:

• Rust of doors, hinges, attachments, damper assemblies and firebox assemblies
• Deterioration of masonry, flue lining system, and building materials.
• Ruined floors, walls, ceilings, wall coverings, carpeting, and duct systems.
• Spalling, shifting, and settlement of masonry.

(Note: The affect of water on your masonry is far-reaching. It can even cause a leak in another part of your home, due to water running unseen through walls and ceilings. Chimney leaks can also lead to mold and mildew which leads to chronic respiratory illness.)

Chimney Caps Keep Wind Out

During the summer, gusts of wind can lead to drafts in your house, raising the cost of cooling. During the winter, wind in the flue can lead to difficulty lighting or controlling a fire, as well as leading to drafts when the fire isn’t in use. Chimney caps come with wind deflectors.

Chimney Caps Keep Wildlife Out

Any small critter that can get onto your roof can also get into your chimney. Small animals such as squirrels and chipmunks as well as larger raccoons and opossums have been known to climb into chimneys. When they do, they bring debris, bedding, droppings, and fur that can decompose or ignite. If they get out again, they likely damage the lining with claw marks or holes. If they don’t escape, they can suffocate and die, causing a dangerous obstruction. Chief Chimney Services often sees animal intrusion and specializes in humane animal removal as well as chimney sweep services to return the chimney back to safe function.

Chimney Caps Suppress Unruly Sparks

Many chimney caps are equipped with spark suppressors that extinguish sparks that might have escaped the flue. This function prevents sparks from leaving the chimney and igniting debris on the roof or below, in the yard or landscaping.

All functions of the chimney cap are essential to the proper function of your chimney system. If you’re looking to replace your chimney cap, consider a top-sealing damper. The top-sealing damper, often called the energy-saving damper, attaches to the top of the chimney flue, working as a cap AND damper, saving you money, and providing more protection for the chimney from top to bottom, year-round. Discuss top-sealing dampers and chimney caps with a chimney expert now. Call 631-863-2460.