A customer in Alaska was looking for some specialty mats, these were 4″ thick x 4′ x 20′, to be used as a warehouse shop floor. Concrete floors were not an option due to the permafrost and the cost to pour concrete in that remote region. Frost heaving is a major concern and the reason they chose to use our wood mats as a permanent floor. The heaving caused by expansion of freezing water causes major damage to concrete and pavement.