We use 3/4" Non Formaldehyde pre-finished Maple plywood for all box interiors unless they are visible through glass or open like bookshelves. Those are made of 3/4" non formaldehyde plywoods in the appropriate species to the job.
Materials we don't use and things we don't offer
We do not use particleboard, masonite, melamine or other cheap or formaldehyde rich products. We do not use endangered species hardwoods. We do not do any work on pre-existing cabinets such as re-facing, re-finishing or re-working for new appliances etc.