They can also be put lower on the rows of screws that hold the metal sheeting to the roof batons.
Installing antenna on metal roof.
In order to take advantage of a metal roof as a ground plane you cannot elevate a quarter wave vertical high above a metal roof.
But what if you have a metal roof.
Thus buildings with a metal roof or many metal components will face difficulty watching tv.
So you may want to put the mount on the ridge capping at the top of the roof.
I always recommend mounting tv antennas as high as possible.
Be sure that the antenna can see over the roof.
Thankfully there are special indoor antennae which will circumvent this problem and help you watch tv despite having metal roofs.
The key is that the antenna feed point which is usually at the mounting bracket should be the same physical level as the metal roof to offer the best ground plane effect.
A metal roof discourages the transfer of signal by reflecting it away from you.
You can also buy non penetrating mounts that use weights rather than screws to hold them in place.