Be VERY glad you found them.
Our first house was a Chicago bungalow with two additions on the back. We decided we'd take out the center wall, lift the ceiling to the rafters, and install skylites.
The house had 10" knotty pine paneling, laid horizontally. Since I can't do heights, we paid some of the polish mafia to do the frame work, and I'd finish the inside. Turns out the 2x4s holding up the roof were gone to termites, and only the main roof beam supported on both ends by walls, and the knotty pine paneling were holding it up. The roof was infested, as well as the subfloor under the oak.
We had just married, had very little to no money, lived week to week for a while, and we ended up gutting the home and rebuilding it completely ourselves.
Back then, they could use a very powerfull anti-termite solution that was banned a few years later. But it worked; aafter our epsiode, we had an inspector inspect every 6 months.