It is advisable to test all your boxes if they are durable enough before packing them up. Otherwise, there might be damages if the boxes are in bad condition. A strong box has to hold and support whatever is placed in it. It should be rigid, have no tears, rips, damage on the corners or punctures. Better safe than sorry. Here is how to pack your boxes properly when moving house:
Reinforce the corners and the bottom end of the boxes with tape. Make several lengths at the closing point. This is crucial especially for those boxes that have been used before or are broken on the bottom end. While on transit, the content in the box will not fall through the bottom end.
Heavy items first
Make sure you begin packing the heavier load at the bottom of the boxes and the lighter ones can be on top. This is to prevent exertion of uneven pressure that might lead to boxes tearing while carrying them.