Treat it like an outside antenna.

Wise words, up to a point.

1) Hardly any difference in the face of a near hit. EMP will hit the
antenna through non-conducing roof.

2) No problem with static accumulation, though. That is due to the
direct interaction of wind / rain / snow and outside metal.

3) Also, IMO, reduced risk of direct hit. Old fashioned lighting rods
featured tall spikes to provide a preferental path to ground for a
lightning. Today's standard solution is a set of flat conductors that
still provide a preferential path, but do not stand up "inviting"
bolts, thus reducing somewhat the likelihood of a hit. (They also
affort little or no protection to nearby property, unlike the older
design).

This in not so clear cut though.

If grounded, an attic antenna will become statically loaded anyway as
the bolt potential builds up. The point effect will be there, leading
to a potential dielectric-perforation risk. The roof will indeed
afford additional isolation, depending on how much material (roof +
DRY air) is between the antenna and the moist outside air in an
electrical storm _with_ rain. I don't know the exact figures, but I
think rainstorm bolts are more common that dry air bolts.

Take your precautions!

Filippo