A mast should be guyed for anything over 10 ft. Better yet only go 3-5 ft above the last support.
By using something custom, to strengthen it you can go further, but even if it is strong enough to withstand the wind, it will sway too much for HDTV reception.
I am going about 15 ft by using a 1 1/4 and 1 1/2 mast sleaved over each other. But it sways more than is usable when the wind is over 15 mph! Handled the winter storms fine, I just have to use my attic antenna when the wind is strong.
There are exceptions, like US Tower makes masts that look like flag poles that are very tall, but they are concrete base mounted. Even with these, I would guess a tower would be far more stable in the wind.
This is just my experience. Your situation could be different. You need to know the strength of your mast (they do come in different guages), it's diameter, and the max wind load expected at your location. You also need to know the max wind load based on the effective sq ft area your antenna presents to the wind.
But all this is not too critical, if you properly locate it so it can blow over in a storm safely, ie away from power lines. In some places people need new antennas regularly, since most are pretty flimsy. The big issue is what a bit of swaying does to reception. You really don't want to see your antenna move. If it moves an inch or two that can cause glitches!
By using something custom, to strengthen it you can go further, but even if it is strong enough to withstand the wind, it will sway too much for HDTV reception.
I am going about 15 ft by using a 1 1/4 and 1 1/2 mast sleaved over each other. But it sways more than is usable when the wind is over 15 mph! Handled the winter storms fine, I just have to use my attic antenna when the wind is strong.
There are exceptions, like US Tower makes masts that look like flag poles that are very tall, but they are concrete base mounted. Even with these, I would guess a tower would be far more stable in the wind.
This is just my experience. Your situation could be different. You need to know the strength of your mast (they do come in different guages), it's diameter, and the max wind load expected at your location. You also need to know the max wind load based on the effective sq ft area your antenna presents to the wind.
But all this is not too critical, if you properly locate it so it can blow over in a storm safely, ie away from power lines. In some places people need new antennas regularly, since most are pretty flimsy. The big issue is what a bit of swaying does to reception. You really don't want to see your antenna move. If it moves an inch or two that can cause glitches!
