Untreated trusses. How long will they last in the rain?

I’m about to order some trusses for my garage and the quotes have all come back for untreated timber. I’ve not done this before but I assumed they would be treated. I mean, it’ll take me a couple of days to get the roof watertight.

The weather’s about to get a bit rubbish, so I’m wondering how long it would be OK to leave untreated trusses in the wet before they get damaged.

Any opinions?

it will probably take several years to get any rot to the timber if off the ground
if they have metal plates or ply you should be ok for several days
if they have mdf/chipboard do not let them get wet