Using Wax Fire Logs with Care

Although sawdust and wax composition fake fire logs offer convenience, if not properly used, they can create safety hazards.

• Do not break apart wax fire logs.

When poked or broken apart, artificial fire logs can cause a flare-up (sudden increase in burn rate) and possibly even an explosion and chimney fire.  Homeowners in Kansas City, Missouri, faced over $11,000 in damage when a poked wax log exploded and ignited a chimney fire.

This damage to the smoke chamber of a chimney was caused by a chimney fire ignited by breaking apart a wax fire log. Photo by HearthMasters.

The instructions on the boxes and wrappers of wax logs say not to break them.  This means neither breaking them apart with a poker nor by tossing in a natural log on top of an existing wax log fire.  There are safety reasons to follow these directions.

Additionally, the hot wax can adhere to your poker.  When you remove the poker from the fireplace, that wax can get onto your floors and carpets.  In a worst case scenario, flaming wax can stick to the poker, drip, and ignite the floor or carpet.

• Do not add a wax log to an existing natural wood fire. 

Mixing artificial logs and natural logs can change the characteristics of the fire. Wax logs contain twice the BTUs of energy per pound as natural firewood, so mixing the two can result in an excessively hot fire, one that possibly exceeds the specifications of your fireplace.   Wait until your natural wood fire is out before adding a wax fire log to your fireplace.

• Burn only one wax fire log at a time.

An artificial fire log is designed to burn at a controlled rate.  As the external surface of the wax log burns, it exposes the internal fuel of the log.  A fire with more than one artificial log can disrupt that process.

• Do not use artificial fire logs in your wood stove or in older manufactured fireplaces.

Many manufacturers of wood stove will not honor their warranties if artificial fire logs have been used in the stove.

Read the product label and warranty on your fireplace before you burn artificial logs.  Older manufactured fireplaces have stickers on them that say to use only natural firewood.   If your fireplace was manufactured after most brands of artificial fire logs were UL-Classified for use in zero-clearance fireplaces, there will be no such limitations on the warranty.

• Use a fireplace grate even with artificial logs.

Fireplace grates lift the logs, whether natural or artificial, off of the floor of the fireplace firebox.  This provides an air flow to the burning material.  Not only is the fire easier to start with a fireplace grate, it is easier to maintain.

• You still need a chimney sweep.

Artificial firewood, since it has virtually none of the moisture that natural wood has, does not produce creosote deposits in chimneys.  However, as they burn, wax fire logs do put off a fine soot that many chimney sweeps say is sticky, making it easy for creosote from wood fires to adhere to it.  Some homeowners find they need to have their chimneys swept more often if they are using artificial fire logs sometimes and natural wood fires at other times.

Artificial fire logs are typically composed of dried sawdust and either petroleum wax or a plant-based wax.  They are popular because they can be bought everyplace from the corner convenience store to the grocery store. In addition, many find them easier to light than natural logs. The convenience of artificial fire logs makes them appealing.  

By following the instructions on the wax fire logs and the directions and warranty on your wood stove or fireplace, and the wax logs can be burned as safely as their natural counterparts.