Do you need a mat with a non-penetrating roof mount?

Non-penetrating roof mounts are great. They make it possible to mount antennas and satellite dishes practically anywhere. Just put them up, anchor them with concrete blocks or big jugs of water and you’re all set. The design of a non-penetrating mount means it’s nearly as stable as one bolted to the roof. But what about this pad? Do you need a pad under the mount? What’s the point?

Before answering that question let’s talk a little more about non-pen mounts.

NPRM’s: they’re not just for roofs

Even though they are known as “non-penetrating roof mounts” they aren’t just for roofs. They can be used anywhere you have a flat surface. Think of patios for example. Apartment patios are great for non-pen mounts because they’re nice and flat. Many landlords aren’t happy about your drilling into their buildings, and why would they be? If your landlord doesn’t let you drill a hole to mount your antenna or dish, a non-pen mount is perfect.

I usually don’t recommend non-penetrating mounts at ground level but if you’re looking for a temporary solution that’s a little more permanent than a tripod then they’re perfect. In the long run if you’re going to leave that antenna or dish there, mounting in concrete is probably a better bet. An even better bet is finding a way to mount the thing up high so people can’t bump into it.

Now, about that mat…

The mat is really just a piece of rubber cut to the right size. I recommend them for roofs that are covered in gravel because they’ll even things out and give you a better, flatter surface. I’d also recommend them for composition tile roofs because they’ll help distribute the weight. Composition tiles aren’t the strongest thing in the world and I’ve seen where over time the mount will sort of seep into the tiles and then, you have a problem. Sure, in very hot weather it’s possible that the mat could melt into the tile too but at least you’ll be able to smoothly remove the non-pen mount if you want to.

The mat also provides a cleaner looking install which might be a concern if your non-pen mount is visible. For example, you see this all the time in hotels. The guest rooms look down on the main hotel roof and it’s a mess of conduits and wires and whatnot. A mat will at least keep the antenna installation looking clean.

Finally, the mat provides electrical resistance. Let’s say you put in a non-pen mount for a pitched roof. You did it because you have a beautiful antique copper roof and you don’t want to damage it. I hear you, those things are very nice. However they are going to conduct electricity which is going to make grounding quite a bit more difficult. Using a mat will shield the antenna or dish. You still have to ground it, but it becomes a more conventional process.

In the end though it’s your decision whether or not you use a mat. I like them, and we have a great selection of them at Solid Signal if you agree.

About the Author

Stuart Sweet
Stuart Sweet is the editor-in-chief of The Solid Signal Blog and a "master plumber" at Signal Group, LLC. He is the author of over 8,000 articles and longform tutorials including many posted here. Reach him by clicking on "Contact the Editor" at the bottom of this page.