Flagpole Foundation Dimensions
Ground Set or Shoe Base
Ground Set
Ground Set installations use a foundation sleeve and are the strongest and most common type of flagpole installation. They require burial of the flagpole shaft in a concrete foundation to a depth equal to 10% of the mounting height.
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.
Foundation Dimensions
| Flagpole 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" |
Shoe Base
Shoe Base installations are typically used when an above ground installation is required.
All 20' to 80' flagpoles with a 4"+ butt diameter can be provided in a shoe base installation option.
Foundation Dimensions
| Flagpole Butt Dia. |
AA Base Square | BB Base Height | CC Bolt Projection | Bolt Diameter | Bolt Circle Diameter |
|---|---|---|---|---|---|
| 4" | 7-1/2" | 3" | 2" | 3/4" | 6-1/2" - 8" |
| 5" | 7-1/2" | 3" | 2" | 3/4" | 7-1/2" - 8" |
| 6" | 9-3/4" | 3-1/2" | 2-3/4" | 1" | 9" - 10" |
| 7" | 10-1/2" | 3-11/16" | 2-3/4" | 1" | 10" - 11" |
| 8" | 11-1/4" | 3-15/16" | 2-3/4" | 1" | 11" - 12" |
| 10" (Up to .250" Wall) | 14" | 4-7/8" | 3-1/4" | 1" | 14" - 15" |
| 10" (.312" Wall & Larger) | 14" | 4-7/8" | 3-1/4" | 1-1/4" | 14" - 15" |
| 12" | 7-1/2" | 3" | 2" | 3/4" | 16" - 18" |