I agree with Bill B's response a single or double safety glass on the
outside will be sufficient. I have a few (not as large as your stained
glass) windows including a front door glass and side lites I have made.
So far 20 + years no problems. I also agree to stay away from
plastics, they will scratch and yellow on you. My only concern is the
size of the stained glass window 6' X 8' is very large hopefully the
pane is reinforced enough to
keep it stiff. I usually solder in some reinforcing brass rods to keep
it from flexing on my large stained glass panels.

Jeff and Jennifer Cook wrote:
My wife and I are in the process of a new home construction. We have
purchased a large stained glass window to hang above the stairs (6' x
8').
We are planning on having an outside tempered glass window in front
of the
stained glass. Any tips on what I should have the window hangers do
and not
do? Should I line the inide of the tempered glass with screen or
chicken
wire to keep a rock from coming through or is the tempered glass
sufficient?
Any tips would be appreciated.
Thanks
Jeff