Question Antenna height above metal roof

[RusWilson]

Should a Yagi (or any) antenna be placed a certain height above a metal roof? Mine would be pointing away from my roof, but located next to it at the end of my house.

Thanks, Rus

 

[bill001g]

The issue with the roof in general maybe that is reflects signals into the antenna no matter what distance. In some ways it might help ? When you consider a dish antenna is big piece of metal that reflects signal into the antenna.

I suspect it make no difference. The signal spread at the end of the antenna is very small. If you wanted to know exactly how many inches I suppose you could try one of the fresnel zone calculators