I was curious about what the difference between the 2 are and I googled it and found this...
What is the difference between Luan Plywood and regular good-one-side plywood?
Good one side is a recognized grade for Canadian made Fir plywood. This panel is obviously made from Fir veneer and bonded on exterior grade resins. The face is well sanded, repairs and natural defects (knots, splits, etc) are limited. For further info try the Canadian Plywood Association, www.canply.org/.
Laun is a term to reference a group of wood species. Laun plywood's come in a variety of grades, some of which are similar to Good one side. Launs are usually bonded with interior grad resins and are not equal to Fir plywood in structural strength.
well, only problem I have with the description of lauan is useing interior grade glues...well what about this?
http://www.homedepot.com/Lumber-Composi ... ogId=10053[/i]