The Wood is spoiled as termites tunnel. Drywood termite galleries cut across the grain , consequently weakening the wood . At last the wood is useless . Possibly the fecal pellets may be packed into some galleries.

Although drywood termite damage is slow as compared to subterranean yet considerable damage may occur because detection of drywood termite is often very late. Almost every important commodity is victim of termite damage like wood, trees on your property, books, plants, and even parts of your swimming pools. The value of termite affected property is also low because no one is ready to face this threat in future as well. 

Moreover, if you've come across termites in your residence, the good news is that they can take quite a while before you see any real damage. Five years duration is a normal one until you see any real damage and if the invaders are healthy, they can eat an entire foot of a two-by-four in just a few months. It doesn't sound so bad, but the extend of the damage rely on the fact that how it's spread in your house - the termites don't consume the whole board instead they tunnel around in them. It is really difficult to estimate the loss and how much you would have to need to come out of the damage.