How much load can the rafters in your house support? Well maybe not your PERSONAL rafters, but in general, if someone were to say, store their gold bricks up there, or put a safe up there - something that isn't large but at the same time is very heavy. I supose that it would depend on the age of the house too, for the sake of argument let's say its a 1950's era house.
Would the rafters be able to support a 400 lb load if it were distributed onto 2 rafter beams?