Q. One who lives with non-frum parents who might or will confiscate a sefer if they see it, may he place goyishe books on top of his seforim so that his parents won’t see it?
Similarly, one who comes from a Litvishe mishpacha, and his parents will be upset if they find chassidishe seforim, may he hide them by placing something on top of them, such as clothing or other things?
A. Horav Shlomo Miller’s Shlit’a opinion is that someone subject to this type of issues, should be prepared and have at hand a suitable cover, such as a clean towel, small tablecloth or similar, to cover with proper decorum and propriety the seforim as needed. He might also include a handy briefcase, box or bag, furniture drawer, etc. nearby.
In case of need, if the sefer is in danger of being discarded or destroyed, one may indeed use the method you mentioned. (See Brochos 18a, Shulchan Aruch Y.D. 282: 3, in regard to the permissibility of placing a Sefer Torah under the donkey’s saddle in order to protect it from being stolen).
Rabbi A. Bartfeld as advised by Horav Shlomo Miller Shlit’a