5-over-1

4-over-1
4-over-1
4-over-1 garage on bottom floor
4-over-1 garage on bottom floor
4-over-1 and 3-over-1 in the background
5-over-1 style apartment buildings in Austin, Texas

5-over-1 or over-1s, also known as a one-plus-five or a podium building,[1] is a type of multi-family residential building commonly found in urban areas of North America.[2][3] The mid-rise buildings are normally constructed with four or five wood-frame stories above a concrete podium, usually for retail or resident amenity space.

The name derives from the maximum permissible five floors of combustible construction (Type III or Type V) over a fire-resistive Type I podium of one floor for "5-over-1" or two floors for "5-over-2", as defined in the United States–based International Building Code (IBC) Section 510.2.[1][4] Some sources instead attribute the name to the wood framing of the upper construction; the International Building Code uses "Type V" to refer to non-fireproof structures, including those framed with dimensional lumber.[5][6]

The style of buildings originated with the work of architect Tim Smith in Los Angeles, who took advantage of a change in construction code allowing the use of fire-retardant treated wood (FRTW) to construct buildings up to five stories.[5][7] From this he saw that what became the "Five-Over-One" model would bring the construction costs down substantially, making a 100-unit affordable housing project financially viable.[5]

The style took root in New York and other dense cities in the American Northeast following the revisions in the 2000 IBC edition,[5] and it exploded in popularity in the 2010s, following a 2009 revision to IBC, which allowed up to five stories of wood-framed construction.[8]

  1. ^ a b "Code Path and Requirements for Podium Projects". WoodWorks. Archived from the original on March 29, 2023. Retrieved August 12, 2019.
  2. ^ Sisson, Patrick (December 4, 2018). "Why do all new apartment buildings look the same?". Curbed. Vox Media. Archived from the original on October 30, 2023. Retrieved February 23, 2019.
  3. ^ Fesler, Stephen (May 23, 2018). "City Council Allows Taller Wood Buildings, Reforms Street Vacation Process and Advances Waterfront LID". The Urbanist. Archived from the original on April 15, 2023. Retrieved May 4, 2019.
  4. ^ Malone, Terry (January 2017). "5-over-2 Podium Design". Structure Magazine. Archived from the original on April 15, 2023. Retrieved February 14, 2022.
  5. ^ a b c d Banton, Lawrence (April 16, 2021). "Why All New Apartment Buildings Look Identical". Cheddar News. Archived from the original on February 7, 2023. Retrieved January 31, 2022.
  6. ^ Desmas, Jerusalem (September 10, 2021). "In defense of the "gentrification building"". Vox. Archived from the original on November 15, 2023. Retrieved February 14, 2022.
  7. ^ Cite error: The named reference Bloomberg was invoked but never defined (see the help page).
  8. ^ "Multi-Story Wood Construction" (PDF). Engineering News-Record. March 26, 2012. Archived from the original (PDF) on November 11, 2020. Retrieved February 23, 2019.