I am a occupational therapist and I treat kids in private practice. One of my main Sensory tools require that a swing be attached to the ceiling. I purchased a 2 x 6 kit from a therapy company to to reinforce the eye bolt that will attach to the supended equipment. (www.southpawenterprises.com) When I open up the ceiling I discovered that this part of the house was 2 x 4 construction. My contrator went ahead and installed the unit which which has a load bearing capacity of 500 lbs. My question is,.. Is the 2 x 4 strong enough to support a swing that will be used to provide linear, rotational and orbital swinging for kids that weigh roughly 20 to 80 lbs max??? FYI my landlord said that the ceiling construction was probably 2 x 4 because it was a second floor addition and their is not a second level above just a roof