How to secure the bottom of a moving box, so that it doesn't accidentally open up while lifting when it is filled with heavy items?

Searching on Google suggests that I should use a good packaging tape and do H taping and H+X taping for heavier loads. My question is, "Is this enough?" Will it ensure that the box won't open up?

Last time, I used a 2" styrofoam sheet and cut it in the same dimensions as the moving boxes and placed it in the bottom to ensure that a box doesn't accidentally open from the bottom while lifting. However, I am pretty sure there is a better way of doing this.


The strength of an unmodified box comes from the folds of the flaps at the bottom (or top) and creates a long lever arm of sorts that is secured at the point where the tape is applied. If you trust the material from which the box is constructed, your efforts to secure the flaps properly will prevent a drop-out of the contents.

If you do not trust the material sufficiently, you can reinforce those folded points with corner material. I recently received a shipment of long slender metal rods. Inside the box, the rods were secured to heavy weight card-stock angles, similar to aluminum or steel flange-type material.

Of course, if you don't have easy access to such material and yet do not trust the existing material, reinforcement of those folded points with load-spreading design is your best bet.

I've applied hot glue angles for the same purpose, extending the angles up the sides about three inches and into the box floor the same amount. Liberal application of hot glue provides for reassuring stiffness. In my more recent case, the shipment was a machine tool base of 75 pounds of rectangular steel.

Your previous method of using foam sheet would tend to distribute the load more evenly than without, presuming that you do not have point-force items in the box.

A table leg will bypass all of the above suggestions, causing higher forces on a small segment of the box. Sometimes it's not how you close it up as how well the inside forces are spread around.

Good quality packing tape, perhaps a 3M or Gorilla brand product is suggested. Some of my tape purchases barely made it out the door before it started peeling away!


The best way to ensure the box doesn't open is to not overload it. Taping an H, or an H+X, will certainly help, especially when using a quality tape. On heavy boxes, I typically put 2 or 3 pieces along the bottom seam, making sure they come up the side high enough to have some overlap with the pieces on the top.

If the box is overloaded (by weight or volume), the box can deform and lose some of its strength.

This also makes it easier for those doing the actual moving, as there are no severely heavy boxes (like a big box full of books). Multiple lighter, smaller boxes are better than fewer heavier, bigger boxes.

Look for a tape marked for 'moving' or 'packaging' - those tend to have a stronger adhesive. If the boxes will be stored for any considerable length of time, look for a tape marked for 'storage', as it will better withstand the climate in a typical storage unit.

Note that I'm assuming a typical household move, with weight spread out evenly in the box. Other scenarios may need different considerations.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.