How to Pack a Storage Unit for the Long Term

Two things ruin goods in long-term storage: moisture and the need to dig. Everything below is either keeping water away from your things or keeping your things reachable, and the order you load in decides both.

This guide assumes a stay of months rather than weeks. Sizing the unit is a separate decision, covered in what size storage unit do I need; this is what to do once you have the key.

Before you load: the floor and the moisture plan

Get everything off the concrete. A slab floor wicks moisture from the ground, a spill or a flood in a neighboring unit travels along the floor, and cardboard sitting on damp concrete fails in days. Lay wood or plastic pallets across the floor, or use plastic shelving, so there is an air gap under every item, including the mattress and the sofa.

Then plan for the air. Climate control moderates temperature, not necessarily humidity: CubeSmart’s definition of its own climate-controlled buildings is that they are heated in winter and cooled in summer and “not humidity controlled,” with humidity levels that could be similar to a house because the units are indoors. That is better than a drive-up unit, but it means the moisture you bring in stays in.

• Bring everything in dry. Wash and fully dry fabrics; do not store anything damp from the move.
• Use desiccant (silica gel or calcium chloride tubs) inside sealed plastic bins and near electronics and paper, and replace it on check-in visits.
• No plastic wrap on upholstery, mattresses or wood. It traps moisture and creates a sealed, dark space for mold. Use moving blankets, cotton sheets or breathable mattress bags.
• Stretch wrap is fine on metal and for holding drawers shut, where nothing underneath can breathe anyway.

If you are choosing between a drive-up and an interior unit for a long stay, the moisture plan is the reason to choose interior for anything made of wood, fabric, paper or electronics.

Prepare furniture and appliances

Disassemble what comes apart. Bed frames, table legs, bookcase shelves and desk tops store flat against a wall and stack, and assembled furniture wastes the unit’s height. Put every bolt, screw, bracket and Allen key from one piece in one zip bag, label the bag with the piece’s name, and tape the bag to the piece itself, not to a box you will lose track of.

Wrap wood in blankets and stand table tops and headboards on edge. Put a sheet of cardboard between pieces so a sharp corner does not gouge a finish over months of contact.

Appliances need to be empty, clean and dry. Defrost the refrigerator and freezer and dry the interior. Drain the washer, including the hoses, and run the dishwasher empty then leave it open to dry. Store all of them with the doors propped ajar so air moves through; a sealed refrigerator that was slightly damp when it went in will not be usable when it comes out. Tape the cords to the back. Anything you cannot bring yourself to store should be disposed of properly; the routes for appliances and electronics are in how to dispose of furniture, appliances and electronics.

The loading order

Load the unit the way a warehouse would: heavy and rarely needed at the back and the bottom, light and frequently needed at the front and the top, with an aisle running the full depth.

1. Large, heavy, seldom-needed pieces go in first, along the back wall and the sides: appliances, dressers, the sofa on end on a pallet, mattresses on edge in their bags.
2. Leave an aisle from the door to the back wall, wide enough to walk and turn. It costs floor area and it is the only thing that makes the back of the unit usable without unloading the front.
3. Stack boxes in columns of uniform size, heaviest at the bottom, lightest at the top, and stop at the height you can safely lift a box down from. Most units are 8 feet tall, per CubeSmart’s size guide, but a stack of full boxes at 8 feet is a stack you will not be able to unbuild alone.
4. Labels face the aisle. A box you can see the label on is a box you do not have to open. Write the contents and the room on two adjacent sides, not the top.
5. Fragile boxes go on top of stacks, never under anything, and the way to pack them so they survive months of settling is in how to pack fragile items.
6. Things you will need mid-stay go last, nearest the door: seasonal clothing, tax records, the camping gear, the box of tools.
7. Draw a map before you close the door. A sketch of the unit with numbered zones, kept with the inventory, means you can send someone else to fetch a box.

For box quantities and supplies, the packing box calculator gives counts by home size; expect roughly one roll of packing tape per 15 to 20 boxes.

What you cannot store

Every facility publishes a prohibited list in its rental agreement, and the categories are nearly universal:

• Fuel, propane and flammables: gasoline, kerosene, propane cylinders, paint thinner, and anything with fuel in it, which includes the lawn mower and the generator unless they have been drained.
• Hazardous materials: pesticides, fertilizers, pool chemicals, cleaning chemicals in bulk, car batteries at many facilities.
• Perishables: any food, including pet food and canned goods at some facilities, because of pests.
• Living things: plants and animals, and no living, working or sleeping in the unit.

Many facilities add fireworks, tires, unregistered vehicles, firearms and ammunition, and stolen or unlawfully held goods. Check the facility’s own list before you load, because a prohibited item found in an inspection can void your rental agreement and your protection plan at the same time.

Inventory, photos and insurance

Make an inventory before the door closes: box number, room, contents, and the zone on your map. Photograph each stack and each large piece as loaded, and photograph the closed, locked door with the unit number visible. Keep the inventory and photos somewhere other than in the unit.

This is also your insurance file. A homeowner’s or renter’s policy may cover goods stored off-premises, often at a reduced limit; the facility will offer a protection plan and may require one. Read what each covers for water, mold and pests specifically, because those are the losses that actually happen in storage and they are the ones most often excluded. How coverage for goods in someone else’s custody works, and what a mover’s valuation does and does not cover once the goods leave the truck, is in moving insurance and valuation explained.

A check-in schedule

Storage units fail slowly, so check on the unit rather than trusting it.

When	What to check
Two weeks after loading	Boxes have not settled or tipped; nothing is damp; the lock is yours and intact
Monthly for the first three months	Moisture on walls or floor, any smell of mildew, signs of pests, desiccant replaced
Every season after that	Same list, plus rotate anything you want to keep from creasing, and refresh the map if you took things out
Every month, from home	The rent has been paid; auto-pay is still on the right card

The last row matters more than it looks. A missed payment is the path to a lien sale, and the facility’s process for that is in the rental agreement, so read it once and set the payment to run without you. If the stay stretches past what you planned, compare the running cost with the alternatives in the storage hub and decide deliberately rather than by default.