TTP-23-MAN
Pole Mount - TTP Series
3
Foundation Hole and Pole Guidelines
• Th
e suggestions below are recommendations
only. It is the installer’s responsibility to
validate foundation parameters prior to
installation, a local geotechnical report may
be required to assess soil conditions. We
recommend consulting with a local engineer
familiar with local regulations and build site
requirements, including soil conditions, terrain,
and load criteria (wind, snow, seismic). All
of these parameters may impact foundation
requirements.
• If you are planning to make seasonal
adjustments to the solar array angle, use
the steepest angle that you plan to use for
foundation and pipe sizing to insure that the
pole and foundation are strong enough to
support the array, and that the desired minimum
ground clearance is maintained, at all projected
angles.
• Highlighted lines in the tables on the next 2
pages require schedule 80 pipe for the main
support pole.
• Dig hole according to recommended depth and
diameter. Remove or properly compact any loose material at the bottom of the hole.
• Th
e pipe lengths listed in the following tables are based on having the pole pipe installed 2-3 inches from
the bottom of the dug holes. Use a brick, concrete block, tiles, or other non-organic solid material at the
bottom of the hole to support the pole on, allowing it to be raised above the bottom of the hole and allowing
the concrete to fully encapsulate the pipe pole. If using a thicker material, be sure to allow for the added
thickness when calculating the above-ground and total pipe lengths.
• Set pipe in hole and use a level to insure that it is straight and plumb in all directions.
• Brace pipe to prevent movement while pouring concrete. Pouring so that concrete is in direct contact with
the soil is recommended. If forming or using sonotube, properly compact backfi ll. Allow concrete to cure for
recommended length of time.
Soil Classi
fi
cations
• If in doubt about the soil type and holding strength, consult a local engineer.
• Class 3 - Sandy Gravel and/or Gravel - Lateral Bearing Pressure - 200 lbs/sq ft below natural grade
• Class 4 - Sand; silty sand, clayey sand, silty gravel, and clayey gravel - Lateral Bearing Pressure - 150 lbs/sq ft
below natural grade
• Class 5 - Clay, sandy clay, silty clay, silt and sandy silt - Lateral Bearing Pressure - 100 lbs/sq ft below natural
grade
