Too often, a house is completely designed before the ventilation system is fit in. The resulting installations are often less effective and more expensive than they should be. You'll get better results if you plan out the entire ventilation system early in the design process. Because every house is different and occupant requirements vary, the best ventilation system for one house may be completely different from the system next door. All the various strategies have both advantages and disadvantages, which you should consider while a new house is still in the design phase. Compared with new construction, installing a ventilation system in an existing home usually involves some extra planning and expense. But with a little forethought, it can still be done
