Cardboard boxes will deteriorate due to heat and water and animals and bugs will snack on them in the meantime.
Boxes in attic.
Use the attic to store anything that is impervious to heat.
You want to make sure you can lift the boxes easily and if they happen to tumble over they don t hurt anyone.
Think empty boxes and suitcases.
Joists that are 2x8 or larger can likely support more weight.
A few more universal.
Boxes also break down and disintegrate which will attract pests even more.
Pests are attracted to the cardboard and to the glue used in construction of the box says santoro.
As a very general guide if the joists are only 2x4s don t plan on storing much in the attic other than very lightweight items.
Heat can damage things such as photographs and wood.
Those cardboard boxes stacked up in your attic could become a veritable buffet for mice and bugs if you re not careful.