Nine pounds of water
A dry 48×40 softwood pallet weighs 33 to 37 pounds. The same pallet after a Portland February can weigh 45. That extra water is nine pounds of freight you are paying to move, multiplied by every pallet on the truck. On a 600-pallet shipment it is more than two and a half tonnes of water.
Carriers charge by weight and by cube. Wet pallets quietly inflate the first number on every single shipment, and because the increase is gradual nobody connects the rising freight bill to the uncovered stack in the yard.
What water does to strength
Wood stiffness falls as moisture content rises. Between a kiln-dried pallet at 15% moisture content and a rain-soaked one above 25%, published figures for softwood show meaningful reductions in bending strength and modulus of elasticity — enough that a pallet rated 2,200 lb racked should be treated as considerably weaker until it dries.
The practical rule in our yard: never rack a visibly wet pallet at its published rating. Floor stack it, let it dry, and re-rate it when it is light again. Nobody has ever been injured by being too careful with a wet pallet.
Mould, staining and the food industry
Wet wood grows mould, and mould transfers. For food, beverage, pharmaceutical and cannabis customers this is not an aesthetic issue — it is a product-contact issue that can fail an audit outright.
We keep a separate covered pool of kiln-dried and heat-treated stock for those customers and we will not substitute from the general yard, even when the general yard looks fine. Dry-looking and dry are different conditions, and only one of them passes a swab test.
Storing pallets properly, cheaply
You do not need a building. You need to get the stack off the ground and keep rain off the top. Two spare pallets as a base plus a tarp that actually reaches the sides will do most of the work. Air gaps matter more than complete coverage: a sealed tarp traps condensation and creates exactly the mould problem you were avoiding.
Orientation helps too. Stacks aligned with prevailing wind dry faster, and anything under a roofline drip edge will stay wet all winter. These are small adjustments that change a yard's pallet quality within one season.
What we do about it on our side
Our premium pools are stored covered. Repair stock is kiln-dried before it goes into a companion stringer, because nailing wet timber to dry timber guarantees a split when it shrinks. And we downgrade wet incoming stock rather than selling it as A, which costs us margin and buys us a reputation.
If you receive a delivery from us that arrives wet because it rained during transit, tell us. We will tell you whether to floor-stack it for a week or send it straight back.