Provided is filter unit for a vaporization pipe having improved reliability and manufacturability and lower cost. The present filter unit comprises a wooden filter housing with a through hole. A metal insert fitting is press fit into the hole. A ceramic foam flame filter is disposed inside the insert fitting. The insert fitting preferably has a step ledge for supporting the ceramic foam filter. The metal fitting preferably has a flange (external to the wood filter housing) for improving the stability of the mechanical connection between the insert fitting and filter housing. This design allows for fast assembly with a minimum of labor. Stress and damage to the wood is minimized. The filter housing can have a vertical/longitudinal wood grain direction (parallel with the filter housing hole), thereby reducing the cost of the wood parts and improving the finished appearance.