This Architectural Drawing is of Penthouse and Roof Floor plan. Traditionally, a penthouse is known as the top-floor apartment of a residential building. Today, however, there are several surprising features that can make real estate agents call an apartment a penthouse — even if it's not on the top floor. A penthouse apartment is an apartment located on the top floor of a building, with the term usually being used in reference to apartments in high rise buildings. Penthouses are generally regarded as luxury real estate, and they can be extremely expensive, not least because they take up an entire floor. A roof plan includes roof dimensions, specifications for roof pitch/slope, the placement of vents and drainage, and material specifications. It may also include framing details. Depending on the complexity of the roof, a roof framing plan could include: Dimensions and styles of windows and skylights. For more details and information download the drawing file.