There are so many different fireplace designs and layouts within the home that it is impossible to generalise about their heating effectiveness. The best way for a fireplace owner to approach it is to consider helpful information and then experiment in their specific situation.

Firstly, some words of encouragement. The authors of this website live in a house with a very open floor plan and a centrally located fireplace. It is a 2-story, 3-bedroom cape cod. On a day with an outside temperature in the 40’s, a moderately-hot fire maintains an indoor temperature of 64ºF downstairs/60ºF upstairs without a supplemental heating source. This fireplace, as a sole heat source, reaches its limitations at around 25ºF and below.

Your results may be more or less favourable.

Generally, older homes will be easier to heat with a fireplace(s) than newer. Builders of newer homes often include fireplaces simply for ambience without much thought given to using them as a heat source. Additionally, newer homes tend to be more airtight and may have trouble providing the fresh air requirements of the fireplace.

For those unable to effectively heat with their fireplace, installing a high-quality wood stove or fireplace insert is a satisfying option!

Some tips

An important aspect of an open fireplace is that, when the damper is open, it takes air from your house and moves it up the chimney. This air is replenished by fresh, but colder, outside air. Overcoming this may prove to be impossible for some houses, but there are techniques (besides having an effective fire) to minimise or eliminate this problem, so try them out before giving up!

  1. It is useful to check how your fireplace affects the temperature of your entire home. When you do this, make sure your fire is efficient and hot and has been going for at least an hour.

  2. Check to see how your fireplace affects your thermostat. Without a fire going, turn down your thermostat and take note to how long it takes for the temperature to decrease a few degrees. Then, perform the test again with a good fire going (make sure the indoor temperature is back up to normal and that the outside temperature is roughly the same as the first test). If the temperature decreases more quickly with the fire going, then your central heating will have to work harder and will increase your utility bill. In this case, you will need to isolate the room with the fireplace if possible (see next guideline).

  3. If you have a single fireplace located on the side of a house or otherwise located in a place which undesirably affects the temperature of the rest of the house, you may need to isolate the room containing the fireplace. Close any doors to the room and, if necessary, minimise airflow from gaps around or under the door(s). Crack a window in the room to supply a source of air - preferably a window which won’t cause a cold draft on someone who would otherwise be enjoying the warm fire.

  4. If there are colder rooms in your home when having a fire, this is not automatically a problem. You will need to make an assessment for your specific situation.

  5. Firelogs such as Duraflame, Java-Log, Pine Mountain, etc., are good for low-maintenance ambience fires but produce far too little heat to be useful for heating.

  6. If you have the resources, it may be worthwhile to consider upgrading your fireplace to a well-built Rumford fireplace or even a masonry heater.

You are encouraged to experiment creatively, and you may just find a way to use your fireplace as an effective heater!

Next, feel free to browse through links for further research.

It is worthwhile to note that a room with an air temperature of 64ºF with an open fire feels notably warmer than a room heated to 64ºF with central heating.