what is a duplex apartment?

Duplex apartment can be:

Two Units/houses joined together by a common wall i.e. side by side units. In county tax records it is considered as one house.

Instead of side by side it can also be two up and down units.

If there are three units together then it is called a Triplex.

If there are four units then it is called a Quad or Quadplex.

Usually people prefer side by side units. This way you have a bit more privacy and there is nobody living above you or below you who can get disturbed.

usually a duplex is meant for more than one tenant - so there could be

2 families living there. One upstairs and one downstairs or whatever.

could be considered commercial depending on a few things

http://www.officespaceheaven.com/

http://www.thefreedictionary.com/duplex

hope it helps

We call that a maisonette in the UK.Often wondered what a duplex was!