21 Clark Street


Date: 4/1/2019


An old hotel was being retrofitted into a nursing home in Brooklyn Heights, New York. The retrofit required additional electrical duct banks to run through the first floor. In order to do that the engineer recommended A minimally invasive helical pile deep foundation system was used to support the columns and deal with the limited access.

Project Summary:

  • Helical Pile Type: 1.75″ Square Shaft with 8″ 10″ Lead Section
  • # of Helical Piles: 50
  • Location: Brooklyn Heights, NY
  • Installation Depth: 25-30 Feet
  • Ultimate Pile Capacity: 80 Kips
  • Equipment Used: CAT 301 Excavator, 12K Drive Head
  • Challenge/Unique Aspect: The piles were installed in the basement of the building and there was extremely limited access. The contractor removed the cab of a mini excavator and used 5 foot helical leads and extensions to deal with minimal headroom.
  • General Contractor: Concrete Works Corp