Why Move a Building on Skids?
Some buildings aren't located near any usable roads. The traditional method used in moving a large building is to undermine the building's foundation, installing a series of metal beams with heavy tires attached so that the building may be pulled away. In situations where the building, such as a portable shed, silo, or dairy house, is out in the middle of a field or pasture, there is a high likelihood that the ground is too uneven or rocky to allow this. Likewise there might be a high amount of foliage or snow buildup which would prevent tires from gaining the traction they need to move a building. For those reasons, simple skids are the best alternative.
Typically a building that is placed on skids does not have a true foundation. Its own weight is the only thing holding it against the ground. There is no concrete slab. To that effect one does not need to dig under the foundation, but simply work a number of hydraulic jacks underneath the corners of the building and raise it. This requires that each of the jacks be worked simultaneously to prevent the building from tipping or sustaining damage. Long skids made from solid plastic are slid beneath the side of the building. These skids come in multiple sections, which can be locked together so the skid can be adjusted to the necessary length.
Once the building has been set back down on the skids, clamps set into the sides of the skids are screwed down tightly to ensure the building won't shift off them. Two chains connected are connected to the front of the skids and then to each other in a Y shape, forming a yoke. The end of the chain is then connected to the trailer hitch of a truck. Depending on the size of the building an 18 wheeler may be required, but the skids help reduce friction with the ground, so most trucks with 4-wheel drive are capable of towing such buildings provided they take it slow.