The project has investigated how a separate conditioning chamber can make progressive kilns more efficient. The 2- zone progressive kilns have a decreasing wet bulb depression in the second zone, which leads to low moisture spread even without conditioning chamber. With a separate conditioning chamber the capacity can, however, be increased by shortening the drying time. This is possible since the conditioning phase can be adapted to get a good drying quality without tensions in the cross section of the board. If needed the conditioning chamber can also be used as to extend the drying time which is useful especially when the board dimensions in the kiln is changed. The conditioning face also reduces the moisture spread with 50% compared to batches from chamber kilns with target moisture content is around 18%. When the drying is performed in a level of wet bulb temperatures over 60°C there is less problems with cracks on thicker boards because of the plastic behavior on the wood surface. Progressive kilns with conditioning face can therefore produce greater volumes then from separate chamber kilns with equal quality concerning slicing test gap and even moisture spread. The technical performance of the conditioning chamber was very god on the pilot kiln. The conditioning chamber opens one door on each side when the loading starts, which influence the climate. It was, however, not any problem to get a stable climate after loading/unloading a tray in the conditioning chamber throughout the experiments, but the spray line must be in perfect condition to reach the wet bulb temperature fast enough. Finally the control system to support the kiln operator in his daily work must be developed with more functions when adding a conditioning chamber to the progressive kiln. This system should give some guidance of how to adjust the climate in the conditioning chamber when changing board-dimensions to be able to achieve a good accuracy around the target moisture.