What is the maximum slope allowed for a fireclay flue liner?

The maximum slope allowed for a fireclay flue liner being 30 degrees is based on the need to ensure proper ventilation and effective exhaust of combustion gases. A slope of 30 degrees balances the need for gas flow with the ability to avoid excessive buildup of creosote or other deposits that can occur if the flue is too flat.

When flue liners are installed at an angle, this helps facilitate the rise of hot gases, which contribute to more efficient draft and less chance of backdrafts. Additionally, maintaining this maximum slope helps prevent moisture accumulation, which can lead to the deterioration of the flue material over time.

While steeper angles may seem beneficial for gas flow initially, they can lead to operational issues such as drafts and structural instability if the installation does not adhere to recommended guidelines. Thus, the standard of 30 degrees is set as a safety measure to optimize both performance and longevity of the chimney system.