I just added a boat rack to the top of my TC to haul my canoe. The canoe is presently sitting on it. Sure nice to have it out of the garage. It is one of those green Old Towns. Will it hurt anyt...
We had kayaks strapped to the roof for two years straight (including plenty of time down south with lots of UV).
We had slight color fading. Worse, the nylon hold down straps gradually wore black marks on, or into, the kayaks that I can't seem to remove. Unsightly, but no real damage.