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Tyvek is designed for new homes ONLY.
That said, adding 1/2 to 1" of foam insulation board over sheathing and under siding will do MUCH MUCH MORE than Tyvek ever can.
Best bang for the buck: NEVER Tyvek... ALWAYS foam board insulation.
Tyvek is not an insulation. It is an air barrier. It depends what you are trying to do and you give little information, leaing one to guess.
There is a foam insulation product designed for installing under the vinyl and AL siding, but it is primarily designed to lend support and shape to the siding. It has very little insulation value because it is so thin.
If you are considering adding an inch of solid foam sheathing to the house, it depends where you are in climate. You could do more harm than good to the house by trapping moisture. Tyvek can breathe enough to let that moisture escape.
If you are attempting to prevent wind blowing through the house and control drafting and convection heat loss, Tyvek can help and won't hurt.