Duplex or penthouse — what is the difference?

What is a duplex?

A duplex is a unit that occupies two levels inside a building, joined by a staircase inside the unit itself. You enter once and both levels belong to you as one home: living space and guests below with the bedrooms above, or the reverse. A duplex can sit on the middle floors of the building; the two-level layout inside the unit is what defines it, not its height.

What is a penthouse?

A penthouse is the top unit of a building, on the roof level or the level just below it. It comes with a large private terrace and open views, and it has no home above it, so its ceiling is the building's roof. A penthouse may itself be laid out over two levels with its own internal stair.

Are they both two floors?

Not necessarily, and this is the common confusion. A duplex always has two levels inside the unit — that is what the word describes. A penthouse always sits at the top of the building with the roof terrace, but it can be a single level with a large terrace, or a two-level unit that is also a duplex. So duplex answers how the unit is arranged, while penthouse answers where it sits and what outdoor space comes with it.

Which one gives more outdoor space?

The penthouse: its terrace sits on the building's roof and is the largest private outdoor area in the block. A duplex may have a balcony or a small garden, but one sitting in the middle of the building has a balcony at each level rather than a terrace on the roof.

How do they differ in price?

Both carry a premium over a flat of similar internal space, for different reasons. The duplex sells the internal arrangement — living and sleeping on separate levels, which many families prefer. The penthouse sells position and outlook: the highest floor, the roof terrace and no neighbour above. In the same building, a penthouse with a large terrace is the highest-priced home.

Which suits which buyer?

A duplex suits a family that wants the two levels separated inside one unit and does not need the top floor or a large terrace. A penthouse suits a buyer who values the view, the terrace and the privacy of having nobody above, and who is ready to pay for them.

What should I check in the contract?

Whether the terrace is for the unit's exclusive use or is shared roof space, and where its boundaries fall; whether the internal staircase is counted in the area sold; who maintains the roof and the terrace; and what access rights to the roof the contract grants. Ask for the terrace's own area in writing, because a terrace described as large that is in fact shared space changes both its use and its value. Those written answers, not the label, are what you compare.