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Should I (electrically) ground my TV antenna?

I've heard both: "you must always ground your antenna" and "you don't need to".

I haven't grounded it (at all) yet.

Under what circumstances is it useful or necessary?

I imagine a TV antenna could theoretically be struck by lightning, but I don't know if that's the only reason to ground.

My home is single storey. All 4 of my neighbours within 50m or so have taller antennas. Some have trees twice that tall. A few houses down, there are double storey homes too. My street is lower than surrounding streets and is in a low lying area (does this remove all chance of lightning strikes to my home?).

Grounding is not required by law (where I live).

In my case, would grounding it simply increase the (unlikely) possibility of a lightning strike?

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    Having tall structures nearby means absolutely nothing. Lighting will find what it wants and ground through it. Any other suggestions on your part are just wishful thinking. A teenager was killed near here by direct lightning strike while standing in his front yard. The lightning failed to strike the 70 foot trees on the property perimeter, the antenna on the chimney, the chain link fence or any other structure taller than 5.5ft. It also missed the nearby mountainside that rises behind the property. There are a lot of things lightning will miss in its mile or more distance of travel.
    – Fiasco Labs
    Commented Aug 18, 2013 at 3:46

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Yes, you should have a grounding block wired to a ground rod before the antenna wire enters your home. It won't necessarily prevent all damage from a direct lightning strike, but it will help.

NEC in the States (NFPA 70) says that if you don't ground the grounding box to the same ground rod that is connected to your breaker box, you need a #6 wire between the ground rods. Obviously, that doesn't apply in your locale, but it's still a good idea.

YMMV, but I get excellent digital TV reception from an antenna mounted in my attic. Removes all the worries about grounding, wind, etc.

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    Grounding is always important. It won't help much with a direct lightning hit, but you don't need a direct hit to induce damaging energy.
    – shirlock homes
    Commented Mar 9, 2011 at 10:59
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    Definitely YMMV on the reception. With analog, simple rabbit ears were fine. After the digital switch they weren't anymore. Tried the big antenna in the above garage space first, was only marginally better. Had to give up and install a 30 foot tower, and the signal still flakes out on really windy days. Don't skimp, get the biggest antenna and tower you can, even if you live in the city (like I do)!
    – Brian Knoblauch
    Commented Mar 10, 2011 at 14:27
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    Thanks. I asked this somewhere else too and was told that not grounding the antenna could result in static charge buildup and actually increase the likelihood of a strike - this was what actually convinced me to do it in the end.
    – MGOwen
    Commented Apr 18, 2011 at 23:51
  • Lightning can still go through your roof to your antenna. (less likely though since your roof would probably be wet at the time, and wood is a better conductor than air.)
    – Brad Gilbert
    Commented Jan 30, 2016 at 18:19
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Grounding the antenna will actually help prevent lightning from striking it. During a Thunderstorm, anything conductive that is not grounded, will collect a static charge... as the charge builds up, it'll attract lightning to it. So grounding the antenna, drains off any charge that might build up attracting a strike.

Also an ungrounded antenna, that builds up a charge, can cause silent damage to your equipment, as this charge will discharge down your coax when it builds up a high enough potential, and do 'silent' damage to your TV tuner. You'll just find your TV can no longer tune to any channels. Have you ever heard anyone saying, that after a thunderstorm passed through town, that their TV was no longer working. This can be the cause. It's very important that all antennas and structure wiring be grounded.

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A metal mast should be grounded. At a minimum, use 10 gauge solid or stranded wire run directly to an 8 ft. ground rod. No sharp turns in the wire.

You should also have a good surge arrester on your incoming coax or lead-in wire. It, too, should be grounded.

If you're able to "bond" the ground rod to the house's incoming utility grounding system, do it. 6 gauge will do. If it means running wire 200 feet around the perimeter of the house to reach the electrical ground, I personally wouldn't fool with it.

Grounding the mast and antenna does NOT increase the chances of a direct lightning strike. Quite the opposite.

BTW, I was certified to inspect lightning protection installations for many years (decades).

Your mileage and results may vary. Just my two cents' worth.

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Your antenna IS ALWAYS grounded. If you don't have it grounded directly then the 'other' path to ground is via YOUR TV SET! The difference is that the TV set has quite a bit of resistance which will allow a static charge to build in the antenna while a ground wire can dissipate a small charge before it becomes a problem.

BTW, Did you know that lightning can actually go from the ground to the cloud? http://www.nssl.noaa.gov/education/svrwx101/lightning/faq/

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What we know about lightning. An electrical charge develops in sky (mostly in storm clouds), as the charged area moves with the cloud an opposite charge intensifies in the ground underneath. These electrical charges send out 'feelers' as they try to get together, as these feelers ionize the air the conductivity of the air is reduced and finally the two charges come together and pass a huge amount of electrical energy. The huge current flow induces (electromagnetic field) voltage and current in nearby wiring, a voltage spike that will burn outlets and jap anything that is connected.

My take on this; grounded objects (with relatively low resistance to ground) are the ones that usually get hit.... trees, houses, tall buildings, etc. That's why you're safer in a car (rubber tires), wearing rubber boots, etc. Grounding the antenna is a catch 22, if grounded the electrical charge can intensify more than the house roof itself due to the low resistance path to ground (increase your odds of getting hit?), but you couldn't buy a ground wire big enough to pass the thousands of amps a lightning bolt can have without vaporizing somewhere so there will be damages. If ungrounded the coax shield connection between the antenna and your electronic device (TV) provides a path to ground at the electronic device. A surge protector may help prevent damage from the voltage spikes in the electrical wiring, but this doesn't help with the coax itself.

My opinion, leave it ungrounded and disconnect electronic equipment from the coax and electrical power during a severe storm overhead or very close by, at least it will save the electronics. Nothing can really protect you from the possibility of getting a lightning hit, but the overall odds you will not be are in your favor.

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    This is an ok answer; it's good to hear the opposition's points. But I don't really agree with your conclusion for obvious reasons. Yes, unplug electronics. Yes, grounding increases the odds of the antenna being preferentially hit by lightning (intead of the roof), but (in my opinion) grounding minimizes the damage, especially for nuisance/minor strikes (along with other light duty protective devices like surge protectors). Grounding the antenna is heavy duty protection. Incidentally, most surge protectors operate by shorting (diverting excess energy) to the ground.
    – Ben Welborn
    Commented May 20, 2016 at 17:45
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Electricity follows the path of least resistance, as does lightning. Grounding a tower lessens the electrical potential (voltage) between sky and the ground. It does this by providing a stream of electrons to pass through the tower's lightning rod into the sky. It does this anytime the electrical potential is strong enough to move electrons. Even with a benign looking cumulus cloud, the electrons will stream (if they can) through the air and toward the cloud. This stream of electrons may or may not cause lightning to strike the tower and a lightning rod isn't used to direct where lightning strikes. Nope. A lightning rod, or grounded tower, is used to reduce the electrical potential between the cloud and ground. I apologize that I am unable to offer a link to where I have acquired this information; you'll just have to trust me on this one. Providing a stream of electrons is likely to lower the resistance to the cloud about to strike lightning, but some evidence shows that greater charges existing in nearby structures may cause lightning to make a diversion.

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    So... should the OP ground their TV antenna or not?
    – Niall C. ♦
    Commented Nov 17, 2013 at 2:10
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Better idea to ground your antenna. BECAUSE IF YOUR HIT BY LIGHTNING YOUR TV MIGHT EXPLODE. it may improve reception. Im going to try. When i was a kid we had an ungrounded antenna outside our house on the deck. It had black two wire, and we turned it by hand to get reception. It was hit by lighting seen it with my own eyes and the carpet caught on fire behind old big 29 inch tv. looked like a ball of fire when it hit yagi antenna.

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We always sprayed rubberized undercoating (available at any auto parts store) around the base of our antenna poles (the two feet before it goes in the ground). We live in lightning alley and never have had a direct strike in over 46 years and our antenna pole is 50ft tall due to our location.

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    OP asked about grounding the pole. Do you spray this rubber coating on the piece that's underground as well, or just the bit that's above ground?
    – Niall C. ♦
    Commented Jul 12, 2014 at 5:46
  • Rubberized undercoating may reduce rusting which reduces conductivity and the effectiveness of the pole at draining static charge.
    – user27531
    Commented Nov 1, 2014 at 18:34

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