8-guage...yikes! lol.
Hopefully you and everyone else in the house have time to put on ear protection before you have to shoot the invader...otherwise everyone's ears will be in some sad shape afterwards.
8 Gauge Shotgun Real Time & Slow Motion - YouTube
That's one major reason I like my .45 for home defense...if it did need to ever be fired indoors (and I hope it wouldn't), in terms of decibels, it's no worse than a 9mm or .380, but has much better stopping power (plus, it's a subsonic round) so it's kind of the best of both worlds.
Of course, firing anything indoors without ear protection is going to rattle the old ears...but, I'd rather have temporary hearing loss instead of permanent hearing damage.
That's what always cracks me up in the movies and on TV, they always show these indoor shootouts taking place, with nobody wearing ear protection, yet nobody seems to be bothered by the noise