Re: Routing coax through exterior (block) walls

Aug 14, 2025 Last reply: 11 months ago 1 Replies


I've got a length of RG213u that wants to exit the house and then turn upwards


>to a roofmounted antenna.
>
>For practical reasons, I suspect it should, instead, turn downwards (driploop)
>before heading up. Regardless, I can't exit the wall parallel to the soil
>and then "suddenly" take a sharp bend (up, down or sideways) -- minimum bend
>radius is ~4.5".
>
>So, the bend has to start *inside* the wall.
>
>What are best practices, in this regard? Run a PVC elbow through the wall
>and then snake the cable through that? Let the drip loop sit against the
>outer surface of the wall and turn upwards in that same plane? Mount the
>lightning arrester *there*, above the loop?
>
>And, is it best to route the cable "exposed" vs. hiding it in interior walls?

Start with how to handle a lightning strike.


Joe

Why so?

It should be acceptable to make most of the curve exterior to the wall and just have it stick out a bit.

BTW Do you really need a drip loop in a desert? A rain shield might be easier.

Where I live it is mandatory because it rains so much, but penetrating damp doesn't sound very plausible as a serious problem in Arizona.

I prefer to stay at least 2x minimum bend radius for coax YMMV.

My experience of lightning arresters - even high end ones on chunky copper busbars that are *supposed* to protect mainframes is that against a direct building hit they are useless.

The magnetic induced currents in local wiring loops are so unpredictable and the protection devices save themselves by letting the most expensive terminal concentrator IO boards to fry to a crisp. All of it needed replacing. I was sorely tempted *not* to replace the "protectors".

Take it to the outside at 45 degrees with a downward slope if you must and then curl it back up the wall. Depending on your skill with a cold chisel you can alter the exit angle if you really want to do that.

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