Madd Hatter Chimney Sweep does everything very clean and neatly. Our Sweeps set up tarps and a large shop vac. In this way they keep everything contained to the chimney system. The entire chimney system is cleaned from top to bottom! These steps are taken with both wood and gas fireplace systems. With a Direct Vent Gas Fireplace, a sealed gas fireplace system having a glass window, the system is unsealed. The glass window is then removed to facilitate cleaning of the system. Some Direct Vent Gas Fireplaces will vent out of an exterior wall instead of the roof. These have a Horizontal Termination Cap. The Horizontal Termination Cap or Chimney Cap / Spark Arrestor is also cleaned out to ensure proper venting.