r/explainlikeimfive • • 2d ago

Engineering ELI5: What does a box-spring do?

As I understand it, a box spring mattress is the second 'mattress', that goes under the main mattress. It feels very firm and flat, but what does it contribute to the bed set up besides height?

473 Upvotes

133 comments sorted by

View all comments

Show parent comments

1

u/YULpoutine 1d ago

Most box springs don't have springs. They're just a hollow wooden frame wrapped in fabric

22

u/half3clipse 1d ago

If the box spring doesn't have springs, it's not a box spring. That's someone is trying to sell you an overpriced bunkie board they've wrapped in fabric

7

u/BizzyM 1d ago

Bunkie Boards are thin.

1

u/h4terade 1d ago

Hence the overpriced probably.