How to Seal a Chimney (User’s Guide)

A chimney can be a useful thing to have, but it’s not always the most attractive feature of your home. If you want an unobstructed view or just want to get rid of that ugly stack on top of your roof, then sealing the chimney may be for you. This guide will tell you how to seal a chimney so that it doesn’t leak any more smoke and soot into your home.

Cleaning your chimney is one of the most important parts of maintaining it. As you use your fireplace, creosote builds up and must be removed periodically in order to prevent fires. Cleaning out the soot prevents it from building up and reduces risk for fire. You can clean your own chimney with minimal effort by following these steps:chimney sweep

  • Take off any loose pieces of debris on top of the flue opening. If there’s not much, just brush them down carefully with a soft bristled brush or vacuum cleaner attachment.
  • Remove any remaining debris from inside the flue using a stiff wire brush or broom handle to knock it down. Do not use a dowel rod made from soft wood, this may make the creosote stick to it and get pushed up inside your chimney flue.
  • In addition to cleaning the chimney with a wire brush or broom handle, you can also vacuum out debris using a hose attachment that fits securely into the opening of your appliance at ground level. This will remove any loose material that remains in your chimney’s flue after brushing by hand.
  • Sealing Your Chimney: If you’re looking for an easy way to seal a chimney so smoke no longer leaks through cracks and crevices around its base, then there are several products on the market specifically designed this purpose! You have a couple of choices when it comes to sealing your chimney:
  • You can use a commercial product such as masonry caulk, or you can dig out some mortar and replace the old cement around the base. If you choose this second option, consider hiring a professional who has experience with this type of work. It’s not very difficult but is labor intensive and requires extensive knowledge of bricklaying techniques.
  • The third choice that we highly recommend is using an aerosol foam sealant like Great Stuff Gaps & Cracks – This is probably one of easiest ways to fill in those pesky spaces where smoke escapes from your hearth area. Just spray away! (it’s as simple as that!) There are several other aerosol foam sealants available on the market, so you may want to do some research before deciding which one is best for your chimney.

What is a Chimney?

A chimney is a vertical structure that conducts smoke out of the building. The word comes from French “chimene” or Middle Latin “caminus,” both words are related to Greek κίμνος (kímnos) meaning oven.

The word chimney is often used to refer specifically to a wood-burning fireplace.

A chimney can also be an underground flue gas stack or smokestack, for example at power plants and some petrochemical facilities.

As heating systems became more efficient many homes stopped needing their own dedicated coal-fired furnace in the basement where they once burned hot enough that this was necessary–and instead began relying on smaller heaters burning natural gas, propane, fuel oil (or kerosene), or sometimes just electricity. The term “chimney” now refers only to the exterior termination of what would formerly have been termed a boiler system running under high pressure with superheated steam supplied by one or more large boilers.

Why do you need to Seal a Chimney?

Many chimneys become drafty over time. Air that leaks into the home can cause discomfort, energy loss and even problems with indoor air quality (IAQ). Leaks in the chimney allow combustion byproducts to escape up through your roof or out of vents inside your house – both areas where they should not be!

Making a proper seal at the base of your chimney can help keep combustion byproducts where they belong – in the firebox.chimney

Steps to Seal a Chimney:

  • Remove any loose, flammable material from the top of your chimney.
  • Apply high temperature sealant using an applicator brush or roller at the base of your chimney where it meets with bricks or mortar.
  • Lightly press down on new mortar around the outside edge until secure and flush against the roofing materials. Be sure not to apply too much pressure as this could cause excess heat which can actually damage your chimney! Apply more if needed.
  • While applying sealant is no easy task, you’ll benefit in many ways by taking care of sealing now instead of ignoring leaks that become bigger over time. Proper maintenance will also increase fire safety within your home.
See also
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How to seal a Chimney?

The process is simple. You need to buy a sealant product that can be applied through the flue, around the outside of your chimney, and this will prevent any draft entering into your home by pushing it up and away from you house. The only other thing required for sealing a Chimney is an old towel or cloth as well as gloves, dust mask and safety glasses if necessary – depending on what type of Sealant Product you’re using.

In addition to those materials needed, below are some tips for how to do it yourself: First check with local building codes concerning whether a professional should apply the product first before attempting self-application. When applying ensure all surfaces are thoroughly covered without leaving too much excess until it dries and hardens. Ensure the sealant is only applied to surfaces that actually require sealing, such as where two chimneys meet or any other place there may be a draft coming into your home through your Chimney.

You can ensure you’re doing it properly by using one of those products with aerosol cans which will allow for better control over how much product is being used at a time. If you have done everything correctly then after applying before going inside, wait about an hour to make sure everything has dried up completely so not leave white residue on the outside of your house from excess product drying too quickly.

Once you have applied the product and ensured all surfaces are covered, simply wait for it to dry up. The longer you wait ensures a better sealant but anywhere from six hours should be enough before re-entering your home again after having thoroughly cleaned yourself off with soap and water – including washing your hands afterwards too if necessary.

Which material is needed for sealing a Chimney?

A towel or cloth Safety glasses Dust mask Gloves A sealant product that can be applied through the flue, around the outside of your chimney. All of these are required materials. None of these are materials necessary to complete this task! Please select an option above before submitting.

Why should you have your Chimney Sealed?

  • A properly sealed chimney will prevent smoke from leaking into your home when it’s not in use.
  • If you have a wood stove, fireplace or gas insert for your home, having them professionally cleaned and inspected is recommended by most insurance companies to make sure they are up to code before the heating season starts. It’s always better safe than sorry!
  • A professional chimney sweep will be able to tell you if your flue is in good shape or not, and whether it needs a repair.

What are the Benefits of Sealing my Chimney?

Keeps the heat inside your home, not outside. It will protect you against high heating bills in winter and cool drafts during summer months.

Improves the overall look of your fireplace and chimney.

Is it difficult to seal a chimney?

It is not as difficult as you might think, but there are precautions that must be taken before any work begins. If done incorrectly, sealing could cause more problems than what it’s worth. It’s best to hire a professional to do this if possible since they know how and will ensure all should go according to plan.

What tools would I need for sealing my own chimney?

This can vary depending on who does the job themselves or hires someone else at their expense. In either case, most people have access to basic hand tools such as: hammer, screwdrivers (flat-head and Phillips), drill, utility knife or saw.

What should I expect to pay for sealing my own chimney?

For the average homeowner it will cost between $200-$400 depending on who does the job. If you do it yourself, be sure that all your safety precautions are met before starting work so as not to cause any unnecessary accidents or injuries while working around an open fire or exposed flue pipe.

Is there anything else I should know about sealing a chimney?

Be sure to check with local building codes if applicable in your area prior to beginning this process especially if done by yourself (this is very important). Also note that some jurisdictions require licensing; make inquiries beforehand since this could increase costs substantially.

See also
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Environmental Protection Agency

The EPA states that for every $ spent on routine chimney maintenance, up to $12 is saved in repairs and damage. If you don’t care about spending money and want a better environment (and not your roof), then we suggest sealing the top of the chimney anyway! It doesn’t take much time or effort, either: it can be done in less than an hour. Moreover, this will save your fireplace from damages like corrosion caused by rainwater infiltration during stormy weather events such as hurricanes and heavy snowfall (when water freezes).

Safety Tips

  • Keep a fire extinguisher nearby. You never know when you might need it!
  • Don’t use your chimney if the weather is too hot or cold, and don’t try to burn anything other than wood in your fireplace insert. It can cause a lot of smoke damage to surrounding areas. When possible, wait until after sunset before lighting up inside for cooking purposes.
  • Before you start, make sure that your fireplace is not blocked by any decorations or furniture. When the fire gets going it will be difficult to move items like this away from danger zones if they’re in its path.
  • Make sure to follow the instructions for your chimney cleaner or sealant. Different surfaces require different types of solutions, so this is crucial!
  • Don’t smoke during the process unless you have a carbon monoxide detector in place. If there are any issues with your fireplace insert while it’s lit then get out immediately and call 911 if necessary. Don’t risk injury just because you want to save on electricity costs by using another source of heat at night time!
  • Remember to keep the damper shut during this process. If you have a gas fireplace insert then it should be turned off, too.
  • Don’t try to burn anything other than wood in your fireplace insert! It can cause smoke damage if done improperly. When possible, wait until after sunset before lighting up inside for cooking purposes so that the fire isn’t used as an exterior source of light at night time when visibility is compromised enough already with no additional confusion from bright flames!
  • Before you start make sure that your chimney is clear of any decorations or furniture that could get in the way and threaten safety otherwise. The fire will grow quickly once started making movement difficult since all attention needs to go towards keeping things under control. Don’t risk injury or a lot of damage to your home just because you want to save on electricity costs by using another source of heat at night time!
  • Follow the instructions for your chimney cleaner and make sure that it is compatible with whatever surface type will be involved in this process before applying it as directed. Different surfaces require different types of solutions, so this is crucial!
  • Don’t smoke during the process unless you have a carbon monoxide detector in place since there are obvious risks associated with having an active fire going inside when smoking indoors even if outdoors would normally not pose much harm. If issues arise then get out immediately and call 911 if necessary instead of trying to solve things yourself without risking more trouble than help.
  • Remember to keep the damper shut during this process. If you have a gas fireplace insert then it should be turned off as well before starting!
  • Don’t try burning anything other than wood in your fireplace insert unless you want smoke damage or worse from failing to do so correctly due to lack of compatibility with certain materials and types of surfaces! It can cause a lot of trouble if done improperly especially at night since visibility is already compromised enough by darkness without adding bright fire light on top of everything else. When possible, wait until after sunset before lighting up inside for cooking purposes so that using an exterior source isn’t necessary when doing things like these primarily intended for convenience instead of being required under less safe conditions where flames would serve as the only source of light and attention at night time.
  • Avoid any potential safety hazards by waiting until after sunset to start up your fireplace or indoor fire pit for cooking purposes if there is no other option available since it will be harder to see clearly otherwise with bright flames distracting from limited visibility outside in darkness.
See also
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FAQs

What material is best for sealing a chimney?

Depending on the type of structure and weather exposure, we generally recommend applying several coats of masonry sealant. This will help protect your chimney against water penetration and cracking/flaking due to freezing temperatures. For most structures, our standard recommendation is to use an elastomeric paint-on product such as Atsko Silicone Water Guard or Fireblocker Chimney Flashings (for metal flues). These products form flexible films that adhere well with little preparation required. However, they are not recommended where direct contact with wood surfaces may occur because they can soften some older finishes. If you have concerns about softening existing coatings after application, consider using an asphalt-based caulk or masonry paint instead. Both products are easy to apply and will dry hard with little shrinkage, but they require a bit more preparation before application.

What is the best way to seal around my chimney?

First of all, remember that your chimney needs two layers of protection: one at its base where it meets the roofing material and another against water penetration just above the first level (at least six inches up). At both locations we recommend using elastomeric paints such as Atsko Silicone Water Guard or Fireblocker Chimney Flashings for metal flues—but not if you’re dealing with fire brick lining because these coatings can soften some older finishes. If you have concerns about softening existing coatings after application, consider using an asphalt-based caulk or masonry paint instead. Both products are easy to apply and will dry hard with little shrinkage—but they require a bit more preparation before application.

What sealant should I use to insulate my chimney?

If you are looking to improve your home’s energy efficiency by adding insulation, consider using a product that will serve double duty. For example, our Fireblocker Chimney Insulation can be used as an effective vapor barrier and flashing material for metal flues (you don’t need anything more than this one application). If you have fire brick lining in the chimney structure itself, we recommend applying Atsko Silicone Water Guard elastomeric paint-on waterproofing (available in several colors) and then wrapping it with Fireboard Flexible Flue Wrap. This insulation is self-sealing and helps block drafts from entering through the chimney structure.

What is a chimney balloon?

A common mistake that homeowners make when trying to solve draft problems on their own with home remedies such as ceramic or aluminum heat reflectors, old rags stuffed into openings, etc., is that they simply block the airflow without addressing the cause of the problem—which may be cracks in masonry flues and improperly sized/installed stove dampers. If you discover evidence of these issues but are unsure what to do next, it’s important not to delay getting professional assistance. Another popular DIY solution for sealing drafts involves using an inflatable “chimney balloon” (similar to those used by water damage restoration companies). Unfortunately, this does little more than block the airflow temporarily without dealing with the root cause of draft issues.

What about chimney caps?

Chimneys can be fitted with a range of different types of covers, also known as caps or cowls. Most are designed to keep out birds and other animals while some are meant for blocking rain, snow, sleet, wind-driven debris (leaves/branches), etc., from entering the flue structure during normal weather conditions. Although these products help protect your home against potential damage due to inclement weather—including ice damming that may occur on roofs during winter months—they should never take priority over regular maintenance tasks such as cleaning your chimney’s masonry exterior at least once per year.

Conclusion

The conclusion is that chimneys should be sealed with a product. This can be done by using do-it-yourself products or hiring professionals to seal the chimney. Additionally, it is important to keep the fireplace clean as any soot buildup on metal surfaces will inhibit heat transfer from gas and wood burning appliances. It also keeps hazardous creosote from building up in areas where flammable debris has been allowed to accumulate for extended periods of time which could lead to a fire hazard inside your home or business if not taken care of immediately after becoming aware of its existence!