ed a bark house will last for a long time depending on its usage. the most important factor is fire or even more so , smoke. the heat helps keep it dry and the formaldahyde in the smoke will help preserve it and keep out the bugs. the poles will also last much longer if the ends are fire hardened before going in the ground. most of the digs that archeologists do they find the charcoal remnants of the burned poles and that is how they determine how big the structures were. so if they are finding charcoal from the poles 200 yrs later, the fire hardening obviously helps to preserve the things.
