One of the big risk factors with billboards is extreme weather. But is there a way to strengthen signs to better withstand higher wind levels? In this Billboard Mastery podcast we’re going to review the methods that be used to make signs stronger and to mitigate the risks from heavy storms.
Episode 100: Methods To Weather The Storm Transcript
Webster Dictionary defines strong as able to withstand great force or pressure. Now, in the world of billboards, what that means is can you help that billboard to withstand extreme weather events? This is Frank Rolfe, the Billboard Mastery Podcast. What do you do when the big storm comes? What do you do when the high winds come? What do you do when there's the giant red blotch on the map that signifies a super high intensity storm and it's aiming for your billboards? What can you do in preparation for that moment? Well, let's first go over a little bit about the design of billboards 'cause billboards are inherently built for weather events.
If you look at how a billboard is put together, the billboard traditionally, the panels on the billboard are held on with gravity. There's clips on the backs of the panels and traditionally they are designed that in the high event of a wind, like a tornado, that is not only high wind speed, but also a sucking motion like a tornado is, that it will pull the panels off the sign because the whole goal of the steel monopole sign is to not exert mega force on the pole and you relieve that by getting the faces off the sign. That's why when there's a hurricane heading for Florida, frequently billboard companies will go and take all the panels off because they know the wind load of the hurricane against just the middle frame of the monopole will not have the ability to topple it over.
So signs were designed with weather events in mind and in fact normally to get a permit you have to have engineering on your sign that will stand up to 100 mile an hour wind and that pretty much covers almost everything out there except a direct tornado strike. So it's not as though signs are not really engineered for weather. However, there are some things you can do to help them out. Now on the monopole sign what you can do is you can weld what is called channel. Channel it looks like a three sides of a box like the shoe box with the top missing and when you weld channel to the monopole it gives it great additional structural strength. You often will see that on really tall signs if you ever noticed on a really tall sign you may see this strange assortment of box looking rectangles and they're typically about three or four feet off the ground.
And that's done because they're trying to reinforce the primary breaking point of the monopole. Because a monopole doesn't break off at the ground. When a monopole breaks off it breaks off about three or four feet off the ground because if you take a pencil and hold it with two hands one near the eraser that's the base of it and the other one a little bit higher up you'll see it doesn't just snap off at the eraser, it stops off somewhere in between and that's where you reinforce the monopole sign. Now what if you don't have a monopole sign though then what can you do? Well, wooden signs are not really engineered for high winds because unlike the panels on the monopole they're not held on by gravity, they don't let go and wooden signs are really not as heavily engineered as metal monopoles. And while telephone poles are strong, typically a wooden sign cannot withstand the same pressures as the monopole can.
So what can we do to strengthen the wooden sign then you might say so that when the storm hits the wooden sign it doesn't break and fall over. Well, there's two schools of thought of how to make them better. One which is probably the superior way is to put a second row of telephone poles behind the first row and then braces that connect them and because what now what you're doing is you're displacing a lot of the energy and the gust to the poles behind so it's as though you have two sets of poles holding the sign up as opposed to one. Now you might say well how come all wooden billboards don't have that? Well, the problem is the brace on that can't be so low normally that it fits under the ad face. You actually have to brace the sign farther up so you can't really do that variety of bracing to the wooden side if it's a two-sided sign only a one-sided sign. If you go down the highway you'll see a whole lot of signs that have exactly like I'm talking about, the regular row of telephone poles with the wooden faces on it and then behind that a second set of wooden telephone poles with an angular brace that runs near the top of the side over to the smaller pole.
But what if you have a two-sided sign, then what do you do? Well, then you can do one more item, you can actually put in support cables, metal cables. These attached to the top of the sign and then they go down and connect again to little wooden telephone poles or some other ground anchor to hold them in place. What you're now doing is whether the wind direction is one direction or the other, it's going to help the sign withstand that sudden gust by having that reinforcement along the top of those metal cables.
Now you've seen that I'm sure before on power poles. You'll see power poles sometimes particularly in areas where it's the final pole and long run of poles, where they will have a metal cable that runs from the top of the telephone pole down to an anchor in the ground, same exact thing. So when the energy from the wind comes and hits the sign, it is absorbed by those metal cables that help support it and in that way it reduces the force on the poles because the sign doesn't have the pressure like a lever pushing down on it so it won't snap the poles. What's the downside of the cabling? The downside of the cabling is twofold. Number one, it's awkward to work around, it's hard to mow around, hard to get around, you can't really do it if there's a developed property beneath it because it takes up too much footprint.
But the other problem you have with the metal cables is they will cast a shadow on the sign when the wind is on... When the sun is on that side of the sign. So even though it does give you some protection from the elements, it may also make the sign a little less attractive to the advertiser. The bottom line is that every sign has its own unique amount of risk regarding wind. Signs that are typically in areas that are sheltered by trees or geography like the sign on the side of a hill on the interstate, that one is very unlikely to ever have a weather event because there's won't be a wind, a straight line wind that can actually hit the sign.
The signs that are really exposed are the ones where they're all by themselves, particularly in certain states and areas that are prone to having high straight line winds such as Kansas. So every sign needs to be looked at as an individual to see does it need extra help, does it need extra reinforcement? And if the answer is yes those are a few tips to try and make your sign a little safer when the big winds blow. This is Frank Rolfe the Billboard Mastery Podcast hope you enjoyed this and talk to you again soon.