Flagpole Foundation Dimensions
Ground Set or Shoe Base
Ground Set
Ground Set installations are the most robust and widely used flagpole mounting method. This installation involves burying the flagpole shaft in a concrete foundation, with the depth of the burial equal to 10% of the flagpole's mounting height.
25' Mounting Height Exception
Flagpoles offered in 25' mounting heights are manufactured in a single piece with an overall length of 26'-6". Below grade, 2'-6" will be inserted into the ground sleeve. When the truck and finial are attached, the nominal height of the completed flagpole will be 25'. This industry accepted standard allows shipping in a pup trailer at a significant freight savings. Full 27'-6" shafts are available upon request.
Foundation Dimensions
| Flagpole Mounting Height | A | B | C | D |
|---|---|---|---|---|
| 20'-0" | 2'-0" | 2'-6" | 30" | 24" |
| 25'-0" | 2'-6" | 3'-0" | 36" | 24" |
| 30'-0" | 3'-0" | 3'-6" | 36" | 24" |
| 35'-0" | 3'-6" | 4'-0" | 36" | 30" |
| 40'-0" | 4'-0" | 4'-6" | 45" | 36" |
| 45'-0" | 4'-6" | 5'-0" | 45" | 36" |
| 50'-0" | 5'-0" | 5'-6" | 50" | 42" |
| 60'-0" | 6'-0" | 6'-6" | 60" | 48" |
| 70'-0" | 7'-0" | 7'-6" | 60" | 48" |
| 80'-0" | 8'-0" | 8'-6" | 72" | 48" |
NAAMM's Metal Flagpole Manual offers basic suggestions on foundation measurements in firm, dry soil only using dry tamped sand and 3000 PSI concrete. Soil conditions vary by site. Exact foundation requirements should be verified by a Structural Engineer with knowledge of soil conditions in your locality.
Shoe Base
Shoe Base installations are typically used when an above ground installation is required.
Foundation Dimensions
| Flagpole Butt Dia. | AA Base Square | BB Base Height | CC Bolt Projection | Bolt Dimensions (Dia. x Length x Hook Length) |
Bolt Circle Dia. |
|---|---|---|---|---|---|
| 4" | 7-1/2" | 3" | 2" | 3/4" x 17" x 3" | 6-1/2" - 8" |
| 5" | 7-1/2" | 3" | 2" | 3/4" x 17" x 3" | 7-1/2" - 8" |
| 6" | 9-3/4" | 3-1/2" | 2-3/4" | 1" x 36" x 4" | 9" - 10" |
| 7" | 10-1/2" | 3-11/16" | 2-3/4" | 1" x 36" x 4" | 10" - 11" |
| 8" | 11-1/4" | 3-15/16" | 2-3/4" | 1" x 36" x 4" | 11" - 12" |
| 10" (Up to .250" Wall) | 14" | 4-7/8" | 3-1/4" | 1" x 48" x 4" | 14" - 15" |
| 10" (.312" Wall & Larger) | 14" | 4-7/8" | 3-1/4" | 1-1/4" x 48" x 6" | 14" - 15" |
| 12" | 7-1/2" | 3" | 2" | 1-1/4" x 48" x 6" | 16" - 18" |
All 20' to 80' flagpoles with a 4"+ butt diameter can be provided in a shoe base installation option.
