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Why Does My Fireplace Have Vents?

A fireplace can create a very nice atmosphere. Whether you’re trying to set a romantic tone for you and your partner or simply want to relax while you read a book, it’s a great way to influence the energy in a room. Perhaps you’ve noticed two vents above and below the fireplace. Well, what do they actually do?

Some fireplaces have vents to help with air circulation; the vent underneath your fireplace allows cool air from your room to be sucked into the fireplace. The air heats as it circulates the firebox and exits as hot air through the top vent. 

The rest of this article will explain in further detail the purpose of fireplace vents, how they can cause your home to lose heat, and the methods you can use to save money on your heating bills. 

What Do Fireplace Vents Do?

The Purpose of Vents

The cool air inside your room gets drawn into the fireplace through the bottom vent. It then passes through a chamber that goes around the firebox and connects to the top vent. 

The firebox is the part of the fireplace where the wood is burnt, and therefore where the heat is generated. So as the air circulates, it heats and comes out as hot air through the top vent. This is how your fireplace actually heats your room. 

There are, however, fireplaces that do not have vents. The advantage of ventless fireplaces is that they are comparatively easy to install since they do not require a flue. A flue is a duct that allows the combusted gases to exit the house. 

Since ventless fireplaces burn gas in a way that is cleaner than traditional wood-burning fireplaces, there is no need for a duct since they circulate the gases back into the room. This also improves heating efficiency.

The Drawback of Vents

The disadvantage of having a fireplace with vents is that during winter, when the fireplace is not being used, the cold outside air can make its way into your house through the chimney, and the warm air inside your house can escape. This can lead to a considerable amount of money being wasted on heating bills.

Not to worry, though, as this problem is easily fixed. The heat loss only occurs if the vents are left exposed. If your fireplace has vents, I highly recommend the Seal360 Magnetic Vent Covers – they are very quick to install, and they will completely block the cold air from entering your house, as well as some bad odors which may also be coming from the vents. 

SEAL360 Magnetic Vent Covers (3-Pack), Pockets for Complete Seal, 5.5\u0022 X 12\u0022 (Brown) for Floor, Wall, or Ceiling Vents and Air Registers

Other Ways to Reduce Heat Loss in Your Home

Now that you’ve understood how vents can cause heat loss in your home, you may be wondering how else you can prevent this from happening (pun totally intended). 

You may not realize how much money you’re currently wasting due to heat loss. When your house does not have proper insulation, a lot of hot air escapes, so people are forced to increase the temperature on their thermostat and therefore spend more money than is necessary to stay warm. To reduce heat loss, first, you need to know how your home is losing heat. Let’s get into it. 

How Your Home Loses Heat

There are several ways your house may be losing heat. In all these cases, heat is lost either through conduction, convection, or radiation. Conduction is a direct transfer of heat through solid material, convection occurs via gases or fluids, and radiation transfers heat through electromagnetic waves. Anyway, here are the culprits:

  • The roof 
  • The walls
  • The floor
  • The windows

The Roof

The reason a lot of heat escapes through the roof is that hot air rises. So the heat will escape from your living space into your attic and from your attic to the outside. What you can do to prevent this is to install loft insulation, but first, you need to consider whether the temperature of your attic is important to you or not. 

Maybe you have an office built into your attic, or you are storing items that are sensitive to heat. In this case, you will need to insulate both the joists and the roof itself. The joists make up the horizontal structure, which separates your living space from your attic. By insulating the joists, you prevent heat from leaving your living space. If your attic temperature is not important to you, this is all you need to insulate.

However, if your attic is temperature-sensitive for whatever reason, you will need to insulate the rafters too, which make up the structure that supports the roof deck. By doing this, you will ensure the attic doesn’t get too cold in winter and doesn’t get too hot in summer. 

The Walls

To insulate your walls, you must first check if you have solid walls or cavity walls. As you may have guessed, there is no gap in solid walls, so the insulation must be installed on the interior or exterior walls. Unfortunately, this is more expensive than insulating cavity walls, and it can also reduce your total living space if done on the interior. Having said that, it will save you money in the long run.

If you have a cavity wall, you can hire a professional to inject insulation into the cavity of your wall. Holes will be drilled on the outside of your house to allow the insulation to be injected (don’t worry, they seal the holes with cement once the job is done). This will prevent a considerable amount of heat from being lost.

The Floor

Most houses nowadays are built on a foundation made up of a concrete slab. According to the Department of Energy, insulating your concrete slab can reduce your heating bills by 10-20%.

The Windows

One of your options here is to invest in double-glazing if you don’t already have it. This creates an additional layer of insulation in your windows, but it can be quite expensive. Another way of reducing heat loss via your windows is to invest in curtains such as the NICETOWN Thermal Curtains. These curtains will balance the temperature in summer and winter, and they are made to last.

NICETOWN Thermal Insulated Grommet Blackout Curtains for Bedroom

Keeping Individual Rooms Warm

However, there are other factors to consider since you may be focused on individual rooms losing heat and the house as a whole. For example, maybe you only heat your bedroom at night, and you don’t want the heat to escape.

A very efficient and cost-effective way of preventing this is to get the Holikme Door Draft Stopper; it is a plastic strip that easily attaches to the bottom of your door. Not only does it prevent heat transfer, but it is also designed for noise reduction. So not only can you save money on your heat bills, but you can also make your bedroom more soundproof.

Holikme Door Draft Stopper

Final Thoughts

Now you know what those vents on your fireplace do, how they help to heat your house, and how they can also contribute to heat loss. As I have mentioned, there are many other ways your house can lose heat. Although every method of insulation costs money, it will save you lots of money in the long run by reducing your heating bills, so you may want to consider making an investment. 


  • Jake Alexander

    Jake is a freelance writer from Pennsylvania who enjoys writing about science and sports. When he's not writing for Temperature Master, he can be found watching the NFL or playing basketball with his friends.

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