When you consider the differing regulation and applications, it makes a great deal of sense. Just making a window in the US can cost less than $10 if you hand a

When you consider the differing regulation and applications, it makes a great deal of sense. Just making a window in the US can cost less than $10 if you hand assemble it. Making a window that conforms to all building regulations in your particular area is a huge undertaking that involves highly specialized equipment.