Table 3-9.-Plywood Uses SOFTWOOD PLYWOOD GRADES FOR EXTERIOR USES Grade (Exterior) Face Back Inner Plies Uses A-A A A C Outdoor  where  appearance  of  both sides is important A-B A B C Alternate  for  A-A  where  appearance  of one side is less important A-C A C C Siding, soffits, fences. Face is finish grade B-C B C C For utility uses, such as farm buildings, some kinds of fences, etc. C-C C C C Excellent  base  for  tile  and  linoleum, (Plugged) (Plugged) backing for wall coverings C-C C C C Unsanded,  for  backing  and  rough construction  exposed  to  weather B-B B B C Concrete forms. Reuse until wood Concrete literally wears out Forms MDO B B or C C or Medium density overlay. Ideal base C-Plugged for  paint;  for  siding,  built-ins,  signs, displays HDO A or B A or B C-Plugged High  density  overlay.  Hard  surface; no paint needed. For concrete forms, cabinets, counter tops, tanks SOFTWOOD PLYWOOD GRADES FOR INTERIOR USES Grade (Interior) Face Back Inner Plies Uses A-A A A D Cabinet  doors,  built-ins,  furniture where both sides will show A-B A B D Alternate of A-A. Face is finish grade, back  is  solid  and  smooth A-D A D D Finish  grade  face  for  paneling, built-ins,  backing B-D B D D Utility grade. One paintable side. For backing,  cabinet  sides,  etc Standard C D D Sheathing  and  structural  uses  such  as temporary  enclosures,  subfloor. Unsanded 3-34