Company Blog

How to Select, Store and Use Firewood

Old-timers will tell you the best firewood comes from most any tree that has been cut into logs and well dried or “seasoned” before use, then stacked under covered storage. You really can burn most any tree wood so long as it’s been cured under cover and if you learn to recognize the properties of various wood types so you can burn them most appropriately.

You may have heard the term “green” firewood. Just like firewood that’s been rained on, “green” refers to freshly cut wood. Both green wood and wood that’s exposed to the elements contain excessive moisture, and what happens when this green/wet wood is burned is a primary cause of chimney fires.

A tree has small tubes in it that deliver water from the roots to the trunk and branches. Months after the wood has been cut, there is still water in these tubes. “Seasoning” refers to storing the wood properly to help dry out this moisture.



First Degree: Lighter soot that can be brushed out of the chimney. A sign of using good quality firewood and good burning habits

Second Degree: Shiny flakes of hard tar; still fairly removable with chimney brushes is most cases. Commonly found with chimneys venting a wood stove, or a fireplace that’s been burned with the glass doors closed

Third Degree: A consistency much like sticky tar on a road, evolving to a hard, thick and shiny consistency like peanut brittle. Cannot be cleaned with chimney brushes. Commonly found where one or more of these burning conditions: (1) Burning unseasoned or wet wood (2) Burning wood stoves with a very slow fire (3) Uninsulated chimneys or chimneys built on an exterior wall of the home (4) Chimney is too large for the fireplace or wood stove that it’s venting (5) A tightly constructed home that provides insufficient air to burn the wood efficiently


When wood burns, not all of the chemicals produced are actually burned. Chemicals in the wood combine with moisture and create smoke. When smoke cools down and becomes solid, it leaves a solid residue in your chimney known as CREOSOTE. Creosote is defined in STAGES (see side panel for further description.) Removal of soot and creosote is the objective of sweeping a chimney.

Before wood can actually begin to burn, the water must be boiled off during the combustion process. This water rises up the chimney along with the excessive smoke it produces, creating a nasty tar-like buildup in your chimney. Over time this sticky tar dries out and becomes hard; similar to the consistency of peanut brittle, it’s very difficult to clean out of the chimney without using either harsh chemicals or specially made mechanical devices. This type of buildup is known as “Stage 3” creosote; besides being devilishly difficult for us to remove from your chimney it also tends to cause the most devastating type of chimney fire when this type of residue catches fire inside your chimney.

Prepare in spring and summer for next year’s wood burning

As soon as you stop burning your wood stove or fireplace, please call us to come inspect your chimney and clean it if it’s needed.

Cut or purchase your firewood right away. A tree cut down before February, when the sap begins to flow, is the best choice. Cutting it into logs right away helps the firewood season – or dry out – much faster.

When purchasing firewood, look for wood that’s gray or dark colored and that has small cracks in the ends, a sign that it is seasoned. Wood with bark falling off is the most seasoned because bark requires moisture in order to adhere to the wood. You’ll usually get a price break if you buy your firewood in the off-season.

A CORD OF WOOD is a pile 8’ x 4’ x 4’. A “Face Cord” or a “Rick” is roughly half that; it’s a pile 8’ x 4’ x the length of a log


Cover the top of your wood pile so it can’t get rained on, but leave the sides open to promote air drying. Stack your firewood so it’s not touching the ground, which helps prevent your firewood from absorbing rainwater. Wood pallets will last a couple of seasons for this purpose. Your woodpile should be loosely stacked to help air flow.stack of firewood

What Type of Wood Should I Burn?

Trees are defined as Softwoods or Hardwoods. Softwoods are good for a quick, hot fire and are ideal for getting a fire lit because they ignite quickly. Hardwoods are denser so they burn longer and slower, and are a good choice for a longer, slower fire. Ideally, once the fire is established, try to burn only hardwoods in your wood stove.

Soft Woods Include

  • Pine
  • Douglas Fir
  • White Spruce
  • Cedar

Hardwoods Include

  • Oak (White Oak or Red Oak)
  • Ash
  • Birch
  • Beech
  • Hard Maple
  • Hickory
  • Pecan
  • Dogwood
  • Almond
  • Apple

What Not to Burnmatch lit against black background

Of course, you should only burn natural firewood in your fire pit, fireplace or wood stove. However, the items below deserve a special mention as far as what to avoid.

  • Salt treated or chemically treated wood
  • Wood with paint or varnish on it
  • Plywood or particle board
  • Christmas Trees
  • Cardboard, especially pizza boxes!
  • Waxy paper or paper with colored print
  • Driftwood

How Does Extended Wet Weather Impact Your Chimney?

Many people are drawn to our overall mild weather here in SC’s Upstate Region.   However, if your home has a chimney, the rain and humidity can play havoc with its structural integrity.  In Summertime we are prone to lots of afternoon thunderstorms, and in Wintertime, we can get a frigid cold snap that is often aligned with rain, snow or ice — all of which can do “a number” your chimney.How Wet Weather Impacts Your Chimney - Greenville SC - Blue Sky Chimney

Moisture absorption can impact the state and structure of your chimney, most notably if the water intrusion is combined with very high or very low temperatures and for an extended period of time. Common results of water intrusion in masonry or metal chimneys include:


The most obvious result of excessive water absorption would be a leak.  If you hear water dripping, see water trails or have water actively dripping in your firebox, or smell musty air coming out of your chimney during warm, humid days, you may be dealing with water getting in and staying in your chimney longer than it should.  When it comes to water absorption, sooner is better than later if you want to interrupt the deterioration process that water entry often creates.

Masonry damage:

 If your chimney is brick-built or has a brick or rock veneer, water is your chimney’s worst adversary.  Water exposure can cause the bond between courses (rows of bricks) or mortar and stone to break (cracking between the brick/stone and the mortar).  It can cause bricks to crack or spall (the face of the brick pops off), or even cause bricks fall off the chimney altogether. Once damaged, brickwork becomes even more vulnerable to water intrusion.  Addressing the problem sooner rather than later can go a long way towards preventing further damage and ultimately extending the life of your chimney.


 Rust can take place on any metal part of your chimney unless it is stainless steel or copper.  With extended exposure, rust can run rampant, if not addressed in a timely manner. Regular inspections can detect rust beginning on your chimney’s metal parts. A manufactured prefabricated chimney’s chase cover and flashing are vulnerable.  A masonry chimney’s metal cap or flashing should be monitored regularly. Also check for rust within the chimney (the damper plate) or on gas log components. Some fireboxes are metal. If water entry has been chronic, a metal firebox could be severely undermined by rust and no longer functional (safe to use).  If you think there are parts of your chimney or fireplace that are beginning to rust, a CSIA Certified Chimney Sweep can verify if your issue needs attention and can provide suggestions for resolution.

Creosote buildup:

This is one that is not commonly thought about.  Creosote is a brownish-black, sometimes tar-like substance that often builds up inside a chimney used to vent a woodburning appliance.  This buildup is worsened with increased exposure to moisture. Cold air outside of your chimney, dropping its overall temperature, creates condensation within the chimney when warm air from your fire is released through the flue.  This is worse with uninsulated and exterior chimneys. Factor in that a wet chimney is a cooler chimney and you can see how water absorption can increase creosote build-up. Similar to how your warm breath creates condensation in cold air, the hot flue air condenses and the creosote particles stick to the insides of your chimney.  Keeping the chimney as dry as possible can positively impact this process. Regular inspections will also make sure your flue is as clean as possible and will lessen the chance of a chimney fire that can result from creosote build-up.

Let our trained professionals here at Blue Sky Chimney Sweeps|Bless Your Hearth help determine overall condition, need for maintenance, issues with functionality, and even offer solutions for long-term issues.  Regular inspections/maintenance can help insure there are no issues related to moisture exposure.