We follow NFPA (National Fire Prevention Association) standards. These national standards state that a home that uses a chimney for venting gases should get an annual inspection. NFPA standards state that 1/8in of creosote is considered dangerous. Here in Colorado we burn pine. Pine, even after seasoning has a high moisture content. We have a large amount of pine and we love to burn it here. Chances are the wood you will be buying will be 100% pine or a 50/50 mix pine and hardwood. Keep in mind with pine you may get a darker, smokier fire depending on seasoning. Unfortunately more smoke leads to more creosote. Remember an accumulated 1/8th of an inch is considered dangerous. We here at Colorado Chimney Company look forward to removing it for you.