Different mounting methods for different roof conditions.
Penetrating Mount
Bolted through roof deck into structure. Best capacity but requires waterproofing details and structural attachment.
Non-Penetrating
Ballast-weighted base sitting on roof. No roof penetrations but requires significant weight - often 500+ lbs in hurricane zones.
Guy Wire Supported
Cables from mast to roof anchors. Reduces base moment but requires multiple attachment points and cable tension analysis.
Antenna Mount FAQs
What wind loads do rooftop antennas experience?
Rooftop antennas experience horizontal drag forces based on their projected area and shape. A typical 3-foot dish antenna in Palm Beach County at 170 mph might see 300-500 lbs of horizontal force. Panel antennas and yagi arrays have different drag coefficients and wind areas that affect the total load.
How do you anchor a rooftop antenna mount?
Antenna mounts can be anchored through penetrating mounts bolted to the structure, non-penetrating mounts using ballast weight, or guy wires to roof attachments. Each method must resist the overturning moment from wind on the antenna. Non-penetrating mounts require significant ballast - often 500+ lbs for hurricane zones.
Do rooftop antennas need engineering approval in Florida?
Yes. Rooftop antenna installations in Florida require structural engineering review to verify the mount and roof can resist design wind loads. The analysis must include the antenna wind force, mount capacity, roof attachment, and any guy wire loads. Building permits typically require sealed calculations.
What is the drag coefficient for antenna types?
Drag coefficients vary by antenna type: dish antennas Cd = 1.2-1.4, panel antennas Cd = 1.4-1.6, yagi arrays Cd = 0.8-1.0, whip antennas Cd = 1.0. These coefficients multiply by the dynamic pressure and projected area to calculate the total drag force.
Why do antenna mounts fail during hurricanes?
Antenna mounts fail from: undersized mounting hardware, inadequate ballast on non-penetrating mounts, guy wire anchor failure, pole bending or buckling, and roof membrane damage from uplift on non-penetrating bases. Proper engineering prevents most failures.
Calculate Your Antenna Wind Loads
Get the exact drag force, overturning moment, and ballast requirements for your Palm Beach County antenna installation.