TTP-46-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 pole 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 pipe.
• Dig hole according to recommended depth and
diameter. Remove or properly compact any loose
material at the bottom of the hole.
• Th
e pole length listed in the following tables are based on having the pole 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 pole lengths.
• Set pole in hole and use a level to insure that it is straight and plumb in all directions.
• Brace pole 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
