Intermittent heating for drying of small diameter Larch lumbers is investigated experimentally. The lumbers were dried using an experimental drying schedule. Moisture content (MC) of the lumber was continuously recorded and final drying defects were examined. The drying curves showed that the drying rate was a constant in the early stage of intermittent heating drying and decreased evidently when the MC was about 18% (intermittent 2h) and 20% (intermittent 6h). The drying quality reached the second (intermittent 2h) and first grade (intermittent 6h) of the Chinese National Standard. The visual drying defects, especially the check extent along grains were reduced with intermittent heating. When the intermittent time increased, the effect was more obvious.
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