We are considering buying a modular home that is about 6 years old. The home inspection revealed incorrect bolting of the modules (not 4' OC as required) but I noticed a 0.75 to 1.0" gap in the center of home and tapers to almost no gap at the outer walls at each of the marriage joists. Can this be considered normal? Doesn't appear there were any shims or insulation placed in the gap, what should be placed in the gap to ensure proper expansion/contraction and air ventilation? Should we be trying to close the gap at all?