There are some pretty big differences between masonry fireplaces, factory-built fireplaces, wood stoves, and gas appliances. We’re here to break down the Dos and Don’ts of each so that, no matter what type of appliance you have, you know what to do and what not to do, and can enjoy a safer, more efficient fireside experience.
Let’s run through them real quick and then get into the why behind these rules of use…
Masonry Fireplace Dos:
- Do build only small, hot fires and never overload the firebox.
- Do burn well-seasoned wood and keep it stored properly prior to use.
Masonry Fireplace Don’ts:
- Don’t burn cardboard or any kind of loose wrapping paper — no, not even at Christmas!
- Don’t burn pressure-treated lumber or any kind of trash.
Factory-built fireplace Dos:
- Do build small, hot fires.
- Do use well seasoned, dry wood.
- Do make sure you have a screen over top of the fireplace for safety reasons.
- Do shut the glass doors on your factory-built fireplace (if you have them) once the
fire is up and going.
Factory-built fireplace Don’ts:
- Don’t burn cardboard or paper in a factory-built fireplace.
- Don’t throw anything into a factory-built fireplace or burn pressure-treated lumber or any kind of trash.
Wood stove Dos:
- Do build small, hot fires.
- Do burn dry, well-seasoned wood.
Wood stove Don’ts:
- Don’t burn your wood stove very low or starve it of oxygen to make the wood last longer.
Gas log/gas insert/gas fireplace Dos:
- Do read your owner’s manual.
- Do have the system maintained annually.
- Do make sure you have a damper stop in place.
Gas log/gas insert/gas fireplace Don’ts:
- Don’t operate your gas fireplace insert without the glass panel across the front in place.
- Don’t ever put any kind of wood, trash, paper, or anything else in your gas fireplace.
The Why’s Of Wood
Why should I only build small, hot fires in my wood-burning appliance?
Bigger fires might seem like a good idea, but you’ll actually get less heat and less flame from a large fire and more smoke and creosote. This is a don’t across the board for wood-burning appliances, but it’s especially important with factory-built fireplaces, which are made for small fires and designed more for ambiance. But no matter what type of wood-burning appliance you have, don’t overload the firebox or wood box.
Why should I only burn dry, well-seasoned wood?
Whether you have a wood-burning masonry fireplace, factory-built fireplace, or stove, you should only ever burn well-seasoned wood with a moisture content of less than 25%. Why? Because if your wood has a lot of moisture in it when you burn it, the flue gas temperatures will be cooler.
When you drop the flue gas temperatures, condensation forms tar droplets (creosote), and those tar droplets cling and stick to the liner. This liquid tar reduces the size of the inside of the liner, and that just occludes the opening and encourages creosote to build up thicker.
As a result, you have superheated gases going through a smaller area than was intended during engineering and design. And those superheated gases can ignite the creosote and cause a chimney fire.
Won’t my firewood dry out in the fire?
It may be tempting to bring in damp firewood thinking it’ll simply dry out once you get the fire going. The problem is, when you dry your wood out in the fire, steam is created and put into your flue liner or exhaust system. This cools the flue gas temperatures, and as we talked about earlier, cooler flue gas temperatures lead to more creosote buildup and a dirtier, more dangerous chimney system.
How do I know if my wood is dry and ready to be used in my fireplace or stove?
You can always buy wood that’s advertised as seasoned, but the best way to ensure the moisture content is to get a moisture meter, which typically costs $20-40, depending on where you buy it. This is simply a battery-operated probe that you touch to the side of the wood to get a moisture reading. Remember, the goal is to have wood with a moisture content of 25% or less.
How should I store my firewood?
Even if you only ever buy seasoned wood, if you don’t store it properly, you could still be burning damp wood in your fireplace or wood stove, contributing to less heat output and a dirtier, more dangerous chimney.
So how should you store your firewood?
Elevate it. If you’re storing it outside, your firewood needs to be elevated off the ground. If it’s not, groundwater will be soaked up through the stack of wood. It’s no different than if you went outside and sat on the ground — the seat of your pants would get wet. Even if it’s well-seasoned wood, if it’s stacked outside with ground contact, it will wick up moisture. So make sure it’s elevated at least 6-8 inches off the ground.
Stack it strategically. When you stack your firewood, you want to make sure it’s stacked in a way where air can move across the wood to dry it out and keep it dry.
Cover it. Your firewood should always have a protective covering over the top so that when it rains or snows, the wood doesn’t absorb any of that moisture.
When you bring the wood inside and it appears to be dry — maybe it has a grey color to it or when you look at the dull end of it, you can see it’s trying to split — you can check it with your moisture meter to see if it’s ready to be burned.
Why can’t I burn cardboard or loose wrapping paper in my masonry fireplace, factory-built fireplace, or wood stove?
On Christmas morning, it may be tempting to throw the cardboard and wrapping paper from the gifts right into the fire, but don’t ever do this. These materials produce a lot of heat very rapidly, and if you have creosote deposits in your chimney, that amount of intense heat could start a combustion process. The result = a tar fire burning inside of your flue.
Even if you put out the fire in your fireplace immediately by throwing a bucket of water on it, you still won’t extinguish the fire that’s in the flue liner. And in just a few moments, either the terra cotta flue liner will crack or the stainless steel pipe will gap and separate, and now you’re putting superheated gases into either a plywood chimney — setting it most likely on fire — or into a brick chimney that is not made to take the heat. That brick chimney will then transfer the heat to your combustible wall space and potentially set your wall or attic on fire.
Not exactly the kind of Christmas memories you want to make, so put the cardboard and wrapping paper in the recycling bin.
Why can’t I burn pressure-treated lumber or trash in my fireplace or wood stove?
Your wood-burning heating appliance is made to burn dry, seasoned wood only. Trash and pressure-treated lumber create different flue gases, which create different residues that then mix with the normal wood residues. This creates a toxic chemical reaction that can adversely affect the inside of the flue liner.
Why shouldn’t I burn my wood stove low and slow?
Burning a wood stove low and slow is a very common mistake with wood stove owners, but it’s actually counterproductive. Why? Because you’re not getting the full BTU energy off of the wood. You’re never heating it up enough to make that heat radiate or blow into the inside of the home.
What you’re doing is very slowly melting the wood, which creates very dark flue gases. If you go to the top of the chimney or venting system, you’ll see thick black smoke coming out, and If you were to capture that smoke, say in a hot air balloon, you could actually ignite it because it’s all this energy “going up in smoke,” literally.
The very thick, tarry residue in the smoke (creosote) will stick to the inside of your flue liner, building up to the point where it’ll either choke the wood stove or the fire down to where it’s smoky and it won’t work correctly, or it will cause a chimney fire.
In other words, low and slow creates a more dangerous fireside experience. Plus, you’re not getting more heat out of your wood — you’re actually getting less. So keep the fire going hot!
Bonus: Do chimney sweeping logs work?
Chimney sweeping logs have a chemical inside them, and when they burn, the chemical coats the inside of the flue. Then the next time you have a fire going, as the flue temperatures rise, that chemical makes some of the creosote want to flake off and peel. So, chimney sweeping logs do help. The problem is, people get a false sense of security thinking that these logs clean the chimney, which they do not.
It would be like if you were baking a cake or cookies and you sprayed the bottom of the cookie sheet or cake pan with Pam or a similar product. Sure, it’s going to help prevent the cake or cookies from sticking, but that doesn’t mean you don’t have to wash the cookie sheet or pan when you’re done cooking.
So the answer is: in-between times, in conjunction with a yearly inspection and sweeping if needed, a sweeping log is an effective thing to use every few fires (or as recommended on the log packaging). But you still need to have chimney technicians come in and actually sweep the deposits and, using a digital camera system, have a look at the inside of the system and see everything up close and personal.
Can you use sweeping logs? Sure. Are they a replacement for a good sweeping and inspection? No. No log is going to be able to tell you if the flue liner is intact and if there are any gaps, separations, cracks, soft spots, weak spots, baked-on creosote, or other dangers or issues.
The Why’s of Gas
Why do I need to read the owner’s manual for my gas fireplace, gas log set, or gas insert?
You should only ever operate your gas logs or gas insert the way your manufacturer tells you to, so it’s very important to read your owner’s manual. These manuals will let you know just what to do and what not to do for safe, efficient use.
Some of them even have time tables that tell you how long you can burn your unit. For example, if you have a set of unvented gas logs, a lot of manufacturers only want you burning that unit for 3-4 hours at a time. Read your owner’s manual and go with those guidelines so you know how to operate your particular gas appliance safely and efficiently.
Why do I need to have my gas appliances serviced annually?
The National Fire Protection Association states that all venting systems should be inspected annually, and gas appliances are no different. During an inspection and service, an experienced technician will make sure all components are working properly, so you know your gas fireplace, log set, or insert is burning efficiently and performing at peak safety levels.
Why do I need to have a damper stop in place for my gas fireplace, insert, or log set?
Damper stops prevent the damper from closing all the way and are required by most manufacturers. Some units require that the damper be left in the fully open position for safety and performance reasons. It varies from manufacturer to manufacturer, so you need to read your owner’s manual to make sure you’re operating the system correctly.
Why can’t I operate my gas fireplace insert without the glass panel across the front in place?
Your gas fireplace insert is going to be a sealed unit with a glass panel going across the front. You only want to operate it with the panel in place because it makes it safer and more efficient.
In order for the fireplace to create the heat needed to create a draft and put the heat back into your home, it needs to be sealed shut. The glass panel also ensures that the fireplace draws the air from the outside as opposed to from the living space, so you’re not using room air that you’ve already paid to heat to make the fireplace draft or draw or burn.
Why can’t I burn any kind of wood, trash, paper, or anything else in my gas fireplace?
Burning anything other than gas in your gas appliance will affect how the unit burns. Plus, that material has to be cleaned out because it doesn’t totally disintegrate and go away. Your gas logs usually have sand or lava or some kind of crystal underneath the burner pan, and that acts as an insulator and also helps it burn correctly. You don’t want to introduce anything to the inside of the fireplace that’s not supposed to be there.
Still have questions? Give us a call. We’re happy to help!