Burning the Right Firewood
Dense hardwoods like maple, oak, birch and cherry are some of the better woods for heating. Different species of wood are available in different areas, so the best firewood will vary by location.
Stacked firewood © Ecohome
Using softwood is less than ideal for home heating, largely because of how fast it burns. The less dense a wood is, the quicker it burns, meaning the sooner you will need to reload your stove.
In areas of abundant hardwood there is a taboo against burning softwood, but you should keep that in perspective. In British Columbia, most people who heat with wood only use softwood simply because that is all that is available. We happily encourage comments from both softwood and hardwood users, so we can settle this once and for all.
There are many conflicting opinions on burning softwood, some say it causes more creosote, but there are many that say it doesn't. A commonly held opinion is that the pitch in softwood causes creosote, but there is evidence to suggest that is untrue.
Resin (or pitch) leaking from a freshly cut pine tree© creative commons
Pitch is the resin excreted from many coniferous trees, and it is often blamed for gumming up stove pipes along with fingers. But it would seem the real culprit is moisture. When the pitch dries, it acts as sort of a super charged fuel, which is responsible for the pops and crackles that you don't get when burning hardwood.
Regardless of how much more creosote softwood does or does not produce, you should be keeping your chimney clean anyway. So relax, and burn it if you have it. In fact a small softwood fire can be ideal as a quick way to take the edge off of a chilly night without overheating your home and leaving a big coal bed. It is also the best kindling you will find.
In areas where a lot of people heat with firewood, there are often notoriously reputable as well as notoriously shady firewood providers.
If you have a chance, ask others in your region about their experiences rather than just taking the phone number off the side of a truck. You can easily receive wood that is too wet, starting to rot or not the species you were told it was. And it is easy to get shortchanged on a truckload of wood and not realize it until you've stacked it.
moisture meter © jeenda
Purchasing firewood early in the season is often helpful for getting a quality product. By the late fall when people without a secured supply are nervous and scrambling, the price often goes up and the quality goes down.
It might be worth getting a moisture meter to check your firewood, especially if you don't know the source, and check it before the wood gets dumped from the truck. It will cost you $75 to $100 to buy a moisture meter, but avoiding even one winter with wet wood makes it a worthwhile investment. Operation is simply a case of jamming the prongs into the wood and reading the numbers.
Whether you are cutting your own wood or buying it, trees should be cut in the winter before the sap starts to rise, then split and stacked in early spring. When you are shopping for wood, ask when it was cut. Prepared in this way, wood should be dry enough for burning by the fall, which means a moisture content between 15% and 20%.
open sided woodshed for storing firewood © Écohabitation
- Keep your wood high enough off the ground to avoid absorbing moisture.
- Protect it from rain, but keep the sides open so air can flow through and dry it.
- Avoid stacking your wood against your house. It prevents air flow through your wood and can prevent the wall of your home from breathing and shedding moisture as well.
- Build proper corners! Having a woodpile fall apart in the middle of the winter is no fun.
- While you are stacking, be sure to split a variety of sizes so you can more easily maintain the level of fire you need.
- If you stack your wood with exposure to the sun or prevailing winds, that will help ensure it is ready to burn in the fall. Keep your wood covered, but allow it to breath.
Burning wood efficiently
There is something biologically imbedded in us that makes us want to be seen as someone who can produce a good fire, especially when our friends are watching. Endless blowing on, and watching a kindling pile smoke away into nothingness is not good for anyone's ego.
moisture content of firewood © CMHC
A smoking fire is not an efficient fire, as smoke is the result of poor combustion. This is caused by either burning wet wood, or by burning dry wood poorly. An efficient fire should result in no visible smoke leaving your chimney. Smoke means you are polluting more, and you aren't getting as much heat as you should for your money and labour.
- Your fire needs to have ample air to get started, then close it down to burn efficiently. But if you close it down too much you will starve it of oxygen, causing it to burn poorly and create smoke
- A quick way to start a fire is to use a criss-crossed stack of dry softwood with some shredded and crumpled newsprint in the centre and mixed in, with a couple of thinly split pieces of hard wood on top. Avoid using glossy paper like magazines.
- Make sure you don't have an overly deep bed of ashes; try to keep it to under 2 inches, and ensure the air intake isn't covered.
- Many small pieces will light more quickly than a few big ones as it increases the number of surfaces where flames can ignite. So split your kindling thin.
- To re-ignite a coal bed, don't spread the coals thin, they will probably go out or at least delay the lighting time. Pile coals together near the air intake, and put your thinly split softwood on top.
- Operating your stove below 270 degrees Celsius means your wood isn't burning efficiently or completely. Burning over 500 degrees Celsius regularly will cause metal fatigue in your stove pipe, as well at put you at risk of chimney fires if you have any creosote build up.
Fire logs have become very popular and easy to find. We aren't talking about the 'light the bag' chemical fire logs that became trendy in the 80's for instant Christmas ambience, but rather the modern day equivalent of responsibly manufactured logs for airtight woodstoves.
Different brands of manufactured fire logs will have used different materials and manufacturing techniques, so do some research before making a purchase. The most eco-friendly choice would be local to your region, and won't contain paraffin or resin adhesives to bind the logs.
You can also find fire logs in different sizes, so look into the numbers regarding burning time and BTUs per log. A smaller log will light faster, but a bigger log might serve you better overnight.
stacked fire logs © moosincon
With a moisture content of between 3 and 6% (much lower than firewood) manufactured logs can burn extremely hot, so be careful not to over load it. Putting a log beside rather than on top of the active fire can delay the lighting, which can let you go to bed and extend the burning time. That's just one little strategy for maintaining even temperatures as it always takes some time and thought to figure out the best way to run your fire.
The energy footprint of manufactured logs is greater than that of split firewood, but they save forests and landfills by making use of post-industrial waste, and they burn very efficiently with fewer emissions.
And don't look at the cost on a per log basis; one manufactured log will give you more heat than an equally sized chunk of split firewood. Purchased in quantity, compressed logs can be noticeably more affordable by the BTU than firewood, so consider splitting on a load with a neighbour to help bring the price down.
One thing compressed logs are not noted for however, is leaving a good coal bed. So, if you find yourself starting more fires than you'd like, you could try mixing it with conventional firewood.
At a certain point, fire logs will be burning very hot but they will be very fragile compared to solid wood. Dropping a new log on top can sometimes make them disintegrate into little more than an ash pile, so be careful how and when you load new fuel.