Tent-making bats modify leaves to build refuges. Leaf modification involves energetic and defense costs that should be balanced by the benefits of tent-roosting. The alteration of the leaf’s vascular system reduces the tent’s life expectancy, so to obtain a benefit bats are expected to use tents regularly as long as they are functional and not modify more leaves than necessary. Over two years we documented the dynamics of tent construction and use by Uroderma convexum and other bat species in the palm Sabal mauritiiformis in a Colombian transitional dry forest. We also assessed tent condition and compared it to nonmodified leaves of approximately the same age in focal palms. Probability of tent use by U. convexum varied between 57 percent during a reproductive period and 4 percent outside of this period. Bats cut the main vein of folioles, partially affecting water transport in the leaf. However, there were no differences between tents and nonmodified leaves in deterioration scores or deterioration rates over one year. During two years, 48 tents were lost for different causes, but this loss was balanced by the construction of 51 new tents. Thus, bats maintained an excess of usable tents. Palm leaves are long-lived and seem preadapted to sustain damage and remain viable, particularly in species growing in dry environments. We present several hypotheses to explain the advantage of maintaining a tent surplus.