[Antennas] ladder line questions

[N1DVE Jacqui]

I would like to put up a closed loop, feed it with ladder line and go into a
tuner.  Although I would like to make my own at some point, I will settle
for the insulated 450 ohm variety at this time until I get more ambitious.

So here are the questions:

1- Aside from using a 4:1 balun and using coax into the house, I would like
to know what will interfere with the ladder line that I should avoid.  Can
it be put under a window sill or into a pvc pipe or a metal pipe?  I think
the first two are OK but the metal pipe is not.   If it is interrupted by a
binding post or connector thru  Plexiglas to get through a window I would
think the impedance would be screwed up by doing so.  Is this true? So what
does one do or not do?

2-What is being used to offer some lightening protection to ladder line.
There does not seem to be too much in the way of surge protectors around for
such.

Any help is appreciated and since I just joined the list I hope these
questions have not been beaten to death lately!  Thanks in advance for any
help or comments.