Vent Free, Direct Vent or Fully Vented Fireplaces - How to Choose the Right One

First, let's get an understanding of the venting used for each type of fireplace. The word "venting" refers to the means the fireplace uses to vent its exhaust safely from the room. In the case of Vent Free, exhaust is vented directly into the room. In a Vent Free system, the consumption of gas is limited to a maximum of 40,000 BTU per hour to help prevent the room from being "starved" of oxygen. In a Direct Vent system, a double vent pipe is used (pipe within a pipe). The outer pipe draws fresh air from outside to feed the combustion process while the inner pipe vents out the exhaust from the combustion. A Fully Vented system, including a B-Vent system, uses either a masonry chimney or a B-Vent (double wall metallic pipe). Now that we touched on the three primary methods of venting, we can take a closer look at the pros and cons of each. 1. Vent Free - As mentioned, a Vent Free system vents its exhaust directly into the room. In other words, it does not use a chimney at all. As you can imagine, this can cause a carbon monoxide concern as this system continuously uses oxygen from the room it's being used in. For this reason, Vent Free systems are equipped with an oxygen detection safety pilot which detects when the oxygen level falls below 18%. If this occurs, the gas will automatically be shut off. The pros for this type of fireplace? You can install them almost anywhere in your home. They are very efficient, meaning you get almost 100% of the heat benefit from the fuel you are burning (the heat is not escaping outdoors). The downsides of this type of burning system? You need to buy specific types of burners/log sets specially made for Vent Free systems. You cannot burn wood in them nor regular vented log sets nor other specialty vented products. If you have respiratory-related health conditions, you may want to think twice before installing this type of system. 2. Direct Vent - A Direct Vent system pulls fresh air in and sends its exhaust out through a combined flu system. The flu pipe vents either out of the top or out of the back of the fireplace, for versatility. The flu pipe generally exits through a side wall in your room. The positives for this type of fireplace? No chimney is required, so less expensive to install than a Fully Vented fireplace. They are highly efficient and may be used as a gas wall furnace. If you like a fireplace with a sealed fire box (because of children, cats, etc.) this style may work well for you. The cons? You can't burn wood in it. They require specific types of burners and logs so you cannot use specialty vented products in them. You are not supposed to burn them without the glass cover attached, as this disrupts the air flow in the balanced vent system. 3. Fully Vented - A Fully Vented system is what most of us think of when we think of a traditional fireplace. Most of us think of a fireplace having a full chimney (like the kind Santa Claus comes down). Usually we think of a brick and mortar chimney, but a Fully Vented fireplace can also incorporate a B-Vent flu (a double wall metallic pipe that rises up from the fireplace and out through the roof). Air for combustion comes from the room. The upsides of this type of fireplace? You can burn wood it in. You can purchase a model that helps to make it more heat efficient by having a fire box "float" inside a second box so that air can circulate around the fire box and back into the room. You can burn many kinds of vented fire logs and specialty vented fireplace products in this style of fireplace. Now the cons. For a new fireplace installation, you may spend more money having a chimney built than you would with the other styles. This style is less heat efficient than the other two styles. Hopefully, you have a much clearer understanding of the three types of fireplaces that were discussed. After reading the various points on each, you may have very valid reasons for choosing one over the other to suite your needs. I'm glad this article helped you make this decision. Personally, I choose Fully Vented because I like the versatility of being able to use this type of fireplace for a number of different products. New products are coming out all the time and I don't want to be restricted from using them. With Fully Vented, you can switch to different types of products as often as you choose.