attic and vapor cover

Our home is newly built and the attic is well built with good strong flooring over most of it and a light switch and wall socket. But the fiber glass insullation on the rest of the attic floor and sides is not covered at all. I want to cover the fiber glass with a vapor cover without ruining or damaging the insullation.
The reason I want to cover the exposed insullation is so I could store my christmas ornaments in the attic since there is room and a flooring. But I would like to be able to breath when I do so. The space is adequate and well lighted. I would also like to sweep and spray to keep spiders out so they don't take over.
Does this sound like a good plan? Or would you not do it if you were me?

 

I would not put a vapor barrier over the insulation. Any moisture that gets that far needs to be able to evaporate, and a vapor barrier simply would not allow this to occur. To acheive the storage space, simply lay strips of 5/8" or 3/4" plywood, however wide you can get into the attic, and full length, over the joists. Dust may be something of an issue, but I doubt that spiders ever would be, as long as there is proper insect screening over the various vents for this attic. (Spiders live only in places where they have food available)