Profile Metal Roof Condensation

[orbit123]

I'm in middle of building a large log store. It's going to have a box profile metal roof, open front and slatted timbers on the sides.

I see a suggestion to use a dripstop material on the underside of metal roof sheets to stop drips from condensation but the local supplier (cheapest delivery!) says they don't do that and suggest an insulated sheet to stop condensation.

As this is a log store the underside of the roof is open to the elements - I can't really see much point in an insulated sheet? The top and bottom will be much the same temperature when cold?

The idea of the dripstop material is to hold any water until the day warms a bit and it evaporates - my roof should have the wind blowing under it to some extent though so not sure if this is needed?

Any ideas on what is best - insulated, material underneath or nothing at all?

Thanks.