When comes the time to choose a fireplace or a stove, heat output is a critical factor to consider. If your fireplace generates too much heat for the room, you will be shy about using it when you have company over. If the BTUs are too small it may also be a problem when you need to warm up a space, especially in a power outage scenario.
In every climate zone of the United States and Canada, you do need to heat your homes. Even the warm climate zone will need to turn on the heater for a few cool nights. What factors should you consider that do have an impact on how many BTUs are needed?
Single room or the house
Do you want to warm up a single room or the entire home? If the goal is to supplement heat in our living room or family room, it will require less BTU than if you are aiming at the entire house. The size of the room is important, not only the length and width but also the height of the ceilings. If your house is an open concept, it would be ideal to include the whole open area for the dimensions of the room. Cathedral ceilings will also require as much as double the heat compared to a regular 8-foot ceiling.
Year of construction
When was your house built? Generally speaking, homes that were built after 1990 do offer a much better insulation level, thus requiring less heat than homes built before 1990. If you feel your dwelling is well insulated but built before 1990, it probably is matching the insulation levels of homes built after 1990.
Areas below and above the rooms
Once the location of your fireplace is set, what is below and above the room will play tremendously in the BTU calculation. If the area below the room is not insulated, like a crawled space, the room will feel cold, so it will require more units to feel comfortable. If there is no insulation in the attic above, the heat will escape, as it rises naturally.
Windows
The windows do play a role too in preventing heat from going out. Double glazed windows offer a much better insulation factor than single glazed. But even the best windows are no match to an insulated wall. The greater the window area, the more heat loss there is. Figuring out the window area for the room consist of adding the square footage of each window found in the room where the fireplace is.
BTU efficiency rating
Most fireplaces and stoves do have a BTU rating. That rating is the BTU input. It means that the fireplace is taking in an amount of fuel (wood, gas, pellet, ethanol) to produce fire. The efficiency percentage will tell you the net output you will be getting inside the room. For instance, let’s use the Ambiance Intrigue Fireplace:
- It has a 39,500 BTU rating,
- Its Energuide efficiency is 70.9%,
- The output for your room will then be 28,005 BTU per hour (39,500 x 0.709) when running on high.
Let’s compare with the Heatnglo True 36, similar in size:
- It has an input of 45,500 BTU rating,
- A 57.9% efficiency,
- The net output to your room would be 26,344 BTU.
Although the Heatnglo fireplace burns 15% more gas, it produces 6% less heat. That is why it is important to make the calculations on efficiency to match a fireplace to your BTU need.
A quick note on efficiency ratings: Do not be fooled by ‘steady state’ or ‘in-house lab’ ratings. In North America, there are two scientifically proven and approved methods to measure efficiency on gas fireplaces. The EnerGuide P.4 efficiency and the AFUE. On wood and pellet fireplaces, the recognized method is the CSA B415.1 method.
So how do you properly measure the number of BTUs you need to heat your space? We strongly recommend having a local expert come in and measure your needs. Also, we designeda BTU Calculator made for North American Climate zones and for fireplace needs. Try it out!
Auburn, ALTop Hat Chimney Sweeps 1280 Financial Ct. Auburn, AL 36830 |  | Visit Store Page |
Elk Grove, CACustom Fireside Shops 9097 Elk Grove Blvd. Elk Grove, CA 95624 |  | Visit Store Page |
Sacramento, CACustom Fireside Shops 5455 Auburn Blvd. Sacramento, CA 95841 |  | Visit Store Page |
Durango, CODurango Outdoor Living 140 Rock Point Drive Durango, CO 81301 |  | Visit Store Page |
Durango, COFour Corner Stoves & Spas 3001 Main Avenue Durango, CO 81301 |  | Visit Store Page |
Grand Junction, COStove Depot and Chimney Works 330 North Ave. Grand Junction, CO 81501 |  | Visit Store Page |
New London, CTFamily Hearth and Patio LLC 571 Broad Street New London, CT 06320 |  | Visit Store Page |
Ridgefield, CTYankee Doodle, Inc. 71 Ethan Allen Highway Ridgefield, CT 06877 |  | Visit Store Page |
Dover, DEByler's Stove Shoppe Inc. 1368b Rose Valley School Rd. Dover, DE 19904 |  | Visit Store Page |
Destin, FLDoodlebuggers Service Network 36054 Emerald Coast Parkway Destin, FL 32541 | | |
Bettendorf, IAFireplaces Plus, Inc. 1745 State Street Bettendorf, IA 52722 |  | Visit Store Page |
Post Falls, IDQuality Stoves & Home Furnishings 569 N Syringa St Post Falls, ID 83854 | | |
Rockford, ILAdvanced Chimney Systems, Inc. 3486 Lonergan Drive Rockford, IL 61109 |  | Visit Store Page |
Wauconda, ILGrass Roots Energy, Inc. 28751 N Route 12 Wauconda, IL 60084 |  | Visit Store Page |
Evansville, INFiremaster, Inc. 5300 E Morgan Avenue Evansville, IN 47715 | | |
Jeffersonville, INOlde Towne Chimney & Fireplace Sales 915 Nachand Ln Jeffersonville, IN 47130 |  | Visit Store Page |
Overland Park, KSKansas City Fireplace Center 10470 Metcalf Avenue Overland Park, KS 66212 |  | Visit Store Page |
Erlanger, KYTateBuilder's Supply, LLC 3511 Dixie Highway Erlanger, KY 41018 |  | Visit Store Page |
Littleton, MAWoodstove, Fireplace and Patio Shop, Inc. 60 White Street Littleton, MA 01460 |  | Visit Store Page |
Seekonk, MAThe Fireplace Showcase 775 Fall River Ave Seekonk, MA 02771 |  | Visit Store Page |
Sudbury, MAWoodstove, Fireplace and Patio Shop, Inc. 348 Boston Post Road Sudbury, MA 01776 |  | Visit Store Page |
Duluth, MNDuluth Stove & Fireplace 2431 W Superior Street Duluth, MN 55806 |  | Visit Store Page |
Minneapolis, MNWoodland Stoves & Fireplaces 2901 Franklin Ave. South Minneapolis, MN 55406 | | |
Oakdale, MNEnergy Savers of Minnesota 6298 Highway 36 Blvd N Oakdale, MN 55128 |  | Visit Store Page |
Rochester, MNBrekke Fireplace Shoppe 1904 S. Broadway Rochester, MN 55904 |  | Visit Store Page |
Walker, MNWilkening Fireplace Company 9608 State 371 NW Walker, MN 56484 |  | Visit Store Page |
Fargo, NDHome Heating, Plumbing & A/C Inc. 701 28th Street South Fargo, ND 58103 | | |
Omaha, NEFireplace By Design 13913 R Plaza Omaha, NE 68137 | | |
Epping, NHThe Stove Shoppe 285, Calef Highway Rte. 125 Epping, NH 03042 | | |
Windham, NHThe Stove Shoppe 25 Indian Rock Road Windham, NH 03087 | | |
Hamilton, NJBowden's Fireside - Hearth & Home 1731 Nottingham Way Hamilton, NJ 08619 |  | Visit Store Page |
Voorhees, NJRettinger Fireplace Systems, Inc. 476 Centennial Blvd Voorhees, NJ 08043 |  | Visit Store Page |
St. Henry, OHBuschur's Refrigeration, Inc. 541 N Eastern Avenue St. Henry, OH 45883 |  | Visit Store Page |
Media, PAChimney Cricket 101 State Road Media, PA 19063 |  | Visit Store Page |
Rapid City, SDHebron Brick Company 1543 Deadwood Ave Rapid City, SD 57709 |  | Visit Store Page |
Sioux Falls, SDHebron Brick Company 2211 W. 50th Street Sioux Falls, SD 57105-6525 |  | Visit Store Page |
Vermillion, SDKalin's Indoor Comfort Inc. 710 Cottage Avenue Vermillion, SD 57069 |  | Visit Store Page |
Manassas, VAWinston's Chimney Service 11301 Industrial Road Manassas, VA 20109 |  | Visit Store Page |
Barre, VTChimney Sweep Fireplace Shop 1284 US Rte, 302 Ste 10 Barre, VT 05641-2317 |  | Visit Store Page |
Bennington, VTFriends of The Sun 126 Hicks Avenue Bennington, VT 05201 |  | Visit Store Page |
Manchester, VTFriends of The Sun 159 Depot Street Manchester, VT 05255 |  | Visit Store Page |
Shelburne, VTChimney Sweep Fireplace Shop 3113 Shelburne Road Shelburne, VT 05482 |  | Visit Store Page |
White River Jnct, VTHome Comfort of New England 1255 VA Cut Off Road White River Jnct, VT 05001 |  | Visit Store Page |
Burlington, WIBurlington Fireplace & Heating LLC 857 Milwaukee Ave. Burlington, WI 53105 |  | Visit Store Page |
Madison, WITop Hat 5117 Verona Rd Madison, WI 53711 |  | Visit Store Page |
Morgantown, WVRustic By Design 709 Beechurst Ave. Suite 15 Morgantown, WV 26505 | | |
Laramie, WYHigh Country Stoves & Fireplaces 860 N. 3rd Street Laramie, WY 82072 | | |