To acclimate hardwood flooring, it should be stacked in the room where it will be installed for at least 48 hours. The stack should be off the ground and away from any direct heat sources or drafts. It is important to keep the boards separated with spacers so that air can circulate between them. The boards should also not be exposed to moisture during this time as this could cause warping or buckling of the wood when installed. After 48 hours, your hardwood flooring will have adjusted to its new environment and is ready for installation.