Guide to Capping a Chimney

Roof Care & Maintenance
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Guide to Capping a Chimney

Capping your chimney is a simple way to cover your chimney and protect the inside of your home from adverse weather, dirt, debris, pests, and more. Chimney caps are highly effective and can last for many years with minimal maintenance required. Due to their position at the very top of the roof, most homeowners choose to call in a professional to cap their chimney. However, capping a chimney is a very straightforward process, as long as you have the necessary equipment and feel comfortable to do so.

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Why Cap Off a Chimney?

Chimney capping has a number of benefits, particularly if you live in an older property or a larger home with multiple chimneys.

Save Money

If your chimney is open, it will let warm air and heat escape from your home. This isn’t a problem if you’ve got a roaring fire at the bottom, but if your home is centrally heated, this can quickly become expensive as heat disappears up your chimney. In fact, homeowners could save themselves hundreds of pounds on their heating bills and repair costs just by adding a simple chimney cap.

Prevent Weather Damage

Another benefit to capping off a chimney is weather protection. Wind, rain, snow, and ice can all severely damage your chimney, particularly sections near the top. Plus, any rain, snow, or hail that find their way into your chimney could soon make your flue a breeding ground for rot and mould. This makes a chimney cap a wise investment for any homeowner looking to reduce future repairs.

Keep Pests Out

Creatures such as mice, slugs, and birds can all make themselves a permanent home in an unprotected chimney, causing damage and leaving some smelly debris behind! This can lead to serious structural issues with your chimney, as well as being unpleasant, so we’d definitely recommend capping off your chimney. This is especially important if you have overhanging trees.

Fire Safety

Chimney caps are often designed to also function as spark arrestors. This means that any stray sparks or embers that flow up your chimney flue will not pose a fire risk. This is as a capped chimney prevents sparks or embers from escaping, trapping them in a safe place until they go out.

Stop Downdraughts

Downdraughts can massively affect how well your fireplace performs. This is because when strong winds can enter your chimney space, rather than drawing smoke out, it will actually be blown into your living room. This is both highly unpleasant and potentially dangerous, as smoke inhalation can cause a number of health issues. Capping off your chimney will help to create an effective barrier, preventing downdraughts from happening.

Which Chimney Cap Is Right for Me?

There are a few different types of chimney cap available, each suited to different kinds of chimney and property. Some are designed to act as temporary protection, whilst others offer a more permanent fix.


The C-Cap chimney capper is a unique design that has been growing in popularity in recent years. It is available in multiple sizes and can be easily applied to the majority of UK chimneys. It can be produced in materials such as terracotta and plastic, and serves as a reliable, long-term solution for those looking to cap their chimneys.

C-Caps come with several different features included, such as insect filters designed to prevent bugs from getting into your chimney and creating a nest there. It also provides efficient ventilation that simply wouldn’t be achievable if the chimney was sealed outright. The cap can be installed remarkably easily, with a simple clamping system allowing you to attach it to the chimney with ease and can be fully functional in a matter of minutes.

Metal Chimney Caps

Metal caps are an alternative to C-Caps and are another popular method of closing off disused chimneys. They are made up of the cap fixing straps built-in and a jubilee clip to help you carry out a smooth, quick installation. They also share many of the same features as C-Caps, including highly efficient meshing to stop bugs and birds, as well as allowing for ventilation effectively.

These caps are particularly useful for those with chimneys that they fear are getting older or in danger of falling apart suddenly. The straps built into these metal chimney caps will often help to keep chimneys together even if they are at risk of cracking. They are extremely durable and are able to withstand a range of weather and temperature conditions without issue.

Chimney Cowls

Chimney cowls are not designed for sealing up the chimney completely. In fact, they are more often used on chimneys that are still in use. They are normally used to properly ventilate chimneys that are connected to more modern appliances such as gas fires and wood burners, also helping to protect your chimney of the elements.

However, cowls can also be used as an alternative to chimney capping, especially if you think the chimney may soon come back into use, especially if you plan on connecting to an appliance in the near future. There are multiple chimney cowls available from a range of different manufacturers. Most a specialised, and designed to be used alongside a specific appliance, so make sure to some research and planning into what type of appliance you are using, or plan on using, with that particular chimney.

Chimney cowls are also very useful in many of the same ways other cap types are, helping to protect your chimney from bugs, birds, damp and more.

Clay Pepper Pot

Want a more traditional-looking solution? Clay pepper pots have been used for well over a century on the top of many disused chimneys, heling to prevent the ingress of any unwanted dirt or life forms. They are usually fashioned to match not only the chimney of a roof, but the tiles and other roofing materials too.

Pepper pot designs are available from many manufacturers, with plenty of different visual options available to those who are after a more defining look for their chimney tops, though it should be noted that they do lack several features enjoyed by more modern alternatives. For example, they can be prone to allowing rain in through the gaps it leaves when placed on your chimney at times, so sealant may be required to ensure that your chimney stays dry. Along with this, like any clay roofing materials, it is prone to cracking and damaging years on your roof, or after a fall.

DIY Chimney Cap

Another way to cap your chimney is to use materials you may have lying around the home or garden, While not necessarily as reliable as specially made caps and similar products, a series of patio slabs or roof tiles, cut to size in order to avoid putting too much weight on the chimney, may provide the perfect solution for you. It is certainly useful as a temporary measure until you are in possession of more effective solutions. If placed correctly, tiles and slabs will almost certainly keep out the majority of things that threaten the stability of your chimney such as birds and debris, but dust, insects and water may be able to get in through any gaps left by the placement of the materials.

How Do I Cap My Chimney?

Chimney cap installation varies between the different cap types available, though there are similarities between some of the different models.

  • C-Caps can be installed in just a few seconds flat by using the clamps provided to secure it to the inside of the chimney pot. The clamps are spring-loaded, meaning they can adapt to pretty much any sized pot.
  • Metal caps Most metal caps used straps with jubilee fixings, which can again be very quickly applied with just a screwdriver required to tighten the fixing once it has been applied to your chimney.
  • Cowls usually differ in installation depending on the make, but for the most part use fixing straps similar to the metal caps, and are again fixable with just a screwdriver. However, some also use bolt fixings, which are placed over the pot, with bolts being screwed into the outside surface of the pot, preventing it from being blown off.

The best way to know if you are installing a chimney cap correctly is to consult the instructions that are provided with the majority of the most popular brands of cap. Sometimes, installation can differ between each brand, so it is only by consulting the specially made instructions for each specific model of cap that you can be sure you are installing yours correctly. Most chimney caps are fairly easy to install, however, with the process rarely lasting longer than just a few minutes.

How Much Maintenance Do Chimney Caps Require?

Chimney caps don’t usually require too much maintenance once they have been applied to your roof. Most have considerable lifespans and won’t require any action on your part for extended periods of time. However, like all roofing components, this can change in particularly bad bouts of bad weather, negligence or infestation, and you may find yourself needing to act in order to preserve both cap and chimney.

The best way to keep track of your chimney is to check on it frequently to ensure that no new damage or wear has appeared. You can also use this time to inspect the security and strength of the cap, which could become dislodged over time. Be on the lookout for worn fixings, mould growth, signs of bird or insect damage and, if metal issued in your cap, rust.

Sometimes, caps become so dislodged or damaged by wear that they will need replacing. This is usually as simple as buying a new cap – thanks to the quick installation times enjoyed by the majority of caps on the market, you won’t be at risk of too much time and hassle spent on getting a new cap back on your roof. Sometimes, replacing just the fixings of your cap is also an option, as it is these that usually wear first. Bolt and strap fixings that most caps use is usually available to purchase on their own and can easily be applied to your cap to replace the old ones.

What About Sealing My Chimney?

Another alternative is to simply seal the chimney altogether, though this is a practice rarely used today. Sealing a chimney will prevent dirt, pests and weather from damaging the flue of your chimney, but will also limit ventilation, sometimes severely.

One of the most effective ways to totally seal off a chimney is to purchase or create your own lead cap. The lead cap can then be bonded onto the chimney, creating a permanent fix that will prevent anything from getting into it. Lead also tends to possess extremely lengthy lifespans, meaning it can potentially last longer than many of your other roofing components without any issues.

The main downside to sealing the chimney with lead is the fact that, while it is waterproof from the outside, the lack of ventilation can allow for water to build considerably on the inside, which cause problems as it will have nowhere to escape to.

So, should you totally seal your chimney? Probably not, but it can be very useful as a temporary fix, very effectively preventing bugs, dirt, debris, birds and rainfall from entering your chimney at all. So long as you plan to replace it with a more effective alternative at some point in the near future, it is a great last-minute solution.

Cost of Capping a Chimney

The cost to cap off your chimney depends on a number of factors, including the type of chimney cap you choose, and the position of your chimney. If you choose to hire a professional, their costs could also increase based upon the height of your chimney, your roof type, and more. For example, if your chimney stack is hard to access, you may need to pay for scaffolding. However, for most British homeowners, capping their chimney should cost around £150.


By now you should have a clearer idea of what method of capping your chimney is best suited to the needs of your property. From more modern answers such as the C-Cap to traditional solutions like sealing, it really is down to what you think will give you the results you are after. Caps are highly efficient and can last for years, but sealing is more permanent.

Capping chimneys can result in a host of benefits to you and your home and is definitely a process to consider. If you are unsure about any of the processes mentioned in this post, don’t hesitate to consult an expert for their advice or assistance on the matter. We also stock a range of chimney materials and accessories, including various types of chimney cowl and other products designed to ensure your chimney remains protected throughout the year.

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