Construction of Pergo Boards
Pergo flooring comes in boards that are 3 feet long, 5 or 8 inches wide and 3/8 inches thick. They have a plasticized surface that contains the wood pattern, a core of high density fiberboard (HDF) and a plasticized backing to seal out moisture. The fiberboard core that is molded into interlocking tongues and grooves on the edges and ends of each board is the most important feature as far as installation and reuse of the boards is concerned. HDF, while strong, is subject to chipping if the boards are mishandled. When the tongues and grooves are chipped, the boards won't lock together.
Installing Pergo
To engage the locking mechanism when installing Pergo flooring, you have to raise one side of the board you are adding to the floor as you push its tongue into the groove of the adjoining board. When you lower the raised end, the boards lock together. You then have to tap the boards together end-to-end using a special tapping block and a hammer. If you perform the operation carefully enough to avoid damaging the HDF locking mechanisms, the boards will be reusable if you decide to take them apart. If you chip the HDF, though, the boards may not lock together a second time.
Disassembling a Pergo Floor
Taking a Pergo floor apart is essentially the reverse of putting it together, with one important difference. Since the boards are locked together end-to-end as well as on the sides, you can't raise a board to disengage the locking mechanism on the side until you disengage the end. You usually do this by lifting the edge of the board slightly and wiggling it, or working a pry bar under the ends that are joined and raising them slightly. Once a gap forms, you work the end of a laminate flooring pull bar into it and tap the boards apart by tapping on the other end of the pull bar.
Considerations
A Pergo floor is subject to moisture damage if a suitable vapor barrier wasn't installed between it and the subfloor. Moisture can warp the boards, and it is especially hard on the HDF core, which must be in good condition if you want to reuse the flooring. Moreover, a discolored or damaged surface also mitigates against reuse of an existing floor. The surface of Pergo isn't wood, and although you can make minor repairs with appropriate products available from the manufacturer, you can't sand or stain it to restore a finish that doesn't look its best.