Concrete Flag paving installed unbound is jointed with kiln dried jointing sand. The sand is brushed and vibrated into the joints using a plate compactor. Important: The paved area should not be cleaned by vacuum road sweepers for a minimum of 3 months. This prevents loss of jointing sand and allows sufficient time for the sand to self-stabilise. If necessary, the jointing sand can be stabilised immediately by using a sand joint sealant.