Chimney top sealing damper and chimney top sealing damper combos

Your traditional damper is installed at the base of the chimney. When the chimney is built the frame for your traditional damper is at the base directly on top of the firebox. After the mason sets the damper frame he builds the rest of the interior of the chimney on top of the damper frame. Due to this it can be difficult and sometimes impossible to replace a traditional damper at the base and requires it to be moved to the top. There are multiple benefits of changing the position from the bottom to the top of the chimney. The primary benefit is that they seal better since they are further from the fire itself.

A traditional damper at the base is a metal plate closing in a metal frame with no rubber gasket or seal between the metal. Being this close to the fire it can not have a rubber gasket seal because it would melt. Just like with a home the lack of a seal can allow some air to enter. The top sealing damper has a metal plate that closes over a rubber gasket. This ensures an airtight seal and can not only help with airflow but also help reduce insects. There are to primary types of dampers either just a top sealing damper or a top sealing damper combo. The primary difference is that just the damper without the combo can allow animal to enter when there damper is left open or if it snows, snow can sit on top of the damper preventing it from opening. Below are pictures showing how each style work and the differences.