It does not matter what kind of wood you burn: as long as it is really, truly seasoned. In the case of some hardwoods, especially oak, it should be seasonedfor at least one year! That means last year’s wood – NOTthis years wood! If you’re wondering about which wood is really the best, or which wood causes the least creosote to build up, the answer is the same properly seasoned wood produces the most heat, and produces the least creosote!It’s not thekind of wood you burn that really makes the critical difference, but whether or not the wood is seasoned. Firewood that hasn’t been split or seasoned with moisture content below 20% isn’t worth a darn! On the other hand, dry, well seasoned wood is just great! Seasoned wood produces a lot of heat, and it burns clean.
If you have trouble starting your fire, or if you have trouble keeping your fire going, you are probably using unseasoned firewood (internal moisture greeter than 20%) – which means that it’s not seasoned. Unseasoned, or green wood, is extremely frustrating and disappointing. If wood is not properly seasoned it will be hard to light. It will keep going out. It will smolder. It won’t put out heat. The moisture content in unseasoned wood does not allow the wood to burn well. It just burns poorly and inefficiently. It is also precisely the moisture in wood which causes creosote to build up at an accelerated rate. One fresh-cut cord of oak may contain enough water to nearly fill six, 55 gallon drums. The moisture content in the wood determines how much heat the fire puts out, and how much creosote will build up in your chimney.
If you are going spend hundreds of dollars on firewood, it’s essential to KNOW that the wood you are buying REALLY IS seasoned! Seasoned wood may look darker, or dingy, or gray compared to green wood – but if you split a piece of seasoned wood – it’s WHITE on the inside. It may seem brittle. It may seem gnarly – but this is because it is just rough unfinished wood. If it is split in quarters, seasoned wood has cracks running through each piece, and a lot of little cracks on the inner rings at the ends of each piece. Tap two pieces of wood together…seasoned wood gives a sharp, resonant sound, like a baseball bat or two 2x4’s coming together. Unseasoned wood sounds dull. Unseasoned wood also has very few cracks, and it has a fresh looking center because it is actually still damp. When firewood is very fresh, the bark will be tightly attached. Avoid these hassles, when you get cold, you will be miserable if your firewood does not produce the heat you need. Only well seasoned wood produces pleasant, trouble free heat.
Depending upon when it was actually cut down and split, softwoods like pine, tamarack or spruce might be dry enough within 3 to 6 months to burn nicely if stacked where the sun and win can reach them for seasoning. But 6 months is not enough for most hardwoods: especially oak. As far as quality is concerned, oak is great wood. Oak is very dense, HARD wood. It burns extremely HOT, and it burns for a long time. A mix of good oak AND softwoods is your best bet. Use the softwood during the day when you are near the stove / fireplace to refill it and the oak overnight for prolonged heat and embers in the morning.
For inexperienced fire-burner’s, pine is probably the most trouble free wood you can buy overall. But, if you read further down you’ll see it’s advantages and disadvantages. The oak that really burns good, is the very same wood that makes good furniture. Most importantly, stay away from large quantities of green wood — unless you have the time and space to season the firewood yourself. Seasoned wood is WHITE inside when it is split. Seasoned wood is comparatively lighter by weight than unseasoned firewood because much of the weight (in the form of water) has been lost. The darker color, the cracking pieces, and the many little cracks on the inner rings at the ends of each piece, are unmistakable signs of seasoned wood.
DO NOT cover your whole wood stack with a tarp …. or you will prohibit evaporation. You can cover the top with a piece of metal roofing, plywood etc. to prevent rain wetting the wood but leave the sides of your stack open to allow air and sunlight in.
What REALLY causes creosote to build up? Creosote is the condensation of unburned, flammable particulates present in the exhausting flue gas (smoke). The actual cause of creosote condensation, is the surface temperature of the flue in which the flue gas comes in contact. Like hot breath on a cold mirror, if the surface temperature of the flue is cool, it will cause the vaporized carbon particles in the flue gas (smoke) to solidify. This condensation is creosote build-up. If the wood you are using is unseasoned / green, the fire will tend to smolder. Wet wood causes the whole system to be cool, and inefficient. But, dry wood means a hot fire! A hot fire means a hot flue, and a hot flue means much less creosote.
Back in the early 1980’s, tests were conducted to discover which kind of wood created the most creosote in a regular “open” fireplace. The results were surprising. Contrary to popular opinion, the hardwood’s, like oak and poplar , created MORE creosote than the softwoods, like tamarack and pine. The reason for this, is that if the softwoods are dry, they create a hotter, more intense fire. The draft created by the hotter fire moves the air up the chimney faster! Because it is moving faster, the flue gas does not have as much time to condense as creosote inside the chimney. Also, because the flue gas is hotter: it does not cool down to the condensation point as quickly. On the contrary, the dense hardwood’s tend to smolder more, so their flue gas temperature is cooler. Thus, more creosote is able to condense on the surface of the flue. So, saying that “pine builds up more creosote than oak” just isn’t true!It is a misunderstanding to think that it’s the sap in wood which causes creosote. It’s not the pitch that is the problem, it’s the water IN the pitch. Once the water in the wood has evaporated, that pitch becomes high octane fuel! That’s why dry, softwoods burn extremely hot.
Which kind of wood is better? That depends on what you want. If you are a first time fire-burner, or if you only want to burn a couple dozen fires a year: go with a DRY softwood, like pine or spruce. Your odds for being happy are higher with pine or spruce, especially if you are just now buying wood for this year. The fresh aroma of pine creates a lovely holiday ambiance. Pine seasons quickly, and when it is dry it is truly delightful, trouble free wood! It’s easy to get going. It smells great. It’s easy to split for kindling. It creates BIG, friendly, luxurious fires! It burns faster than oak or ash. You must feed a stove more frequently to keep it going with pine, and there is no guarantee that there will still be live hot coals in the morning. Also, it is important to know that pine and other softwoods go bad after 5 or 6 years. While pine, spruce or tamarack is great for hot crackling fires in it’s the first few years after being cut, if it is allowed to sit for too many years it just goes dead. A deal on firewood which seems “to good to be true” – might indicate that that it is so old that it is no longer really good wood. This can happen with ANY wood that is allowed to age too long. Still, to be safe in the later part of the season: softwoods are a very good bet. For the serious fire-burner looking to heat exclusively or supplementally with firewood however, cord for cord the hardwood’s are preferable.
Hardwood’s, like oak, ash and birch are the definite choice of the serious fire burner. You may pay $425 for a cord of seasoned oak, and only $295 for a cord of pine. BUT, because the oak is more dense, it weighs much more than the pine. You actually get more for your money with hardwood. In fact, you may get twice, or three times the fire for the money! Because hardwoods are denser, they provide more available fuel in the same space. So, hardwoods burn longer. If hardwoods are properly seasoned, they do burn very, very hot. (Look for oak mixed with softwoods.) The fuel available in hardwood enables stoves or inserts to sustain higher temperatures for significantly longer periods. Also, unless the stove is shut down tight, hardwoods may keep a hot live coal bed for days. So as a rule, airtight stoves, or inserts, perform best with dry hardwoods. It is always important to have a good supply of kindling – because hardwood can be difficult to start. Having a quantity of seasoned softwood on hand is great source of good kindling.
When buying firewood, remember that first and foremost, it must be properly seasoned. The best way to get seasoned wood is to buy your firewood before you need it so it has time to season! Don’t be scared by “green firewood.” Green firewood can be purchased before you need it for trouble free use if you allow it enough time to season.
Remember, when wood gets over 5-6 years old, it does start to deteriorate, so the best wood is 1-3 years old. If you find good dry wood of any kind, you will really enjoy your fireplace or wood stove! But, if you get stuck with green wood you will be one very frustrated wood burner. Most wood for sale is uneasoned wood. If you get serious about wood burning, you must always think one full year ahead! You should always buy this years wood for for NEXT year.Good buys of seasoned wood do come along, but they are often not advertised, because the serious wood burners already know where to go. If you are a first time wood burner, either buy dry, split softwoods, or hunt down really dry, cracking hardwood. You won’t be sorry if you spend a little more money, just to make sure that you enjoy trouble free firewood.