Ask them before they start, better safe then sorry
Make sure they have insurance, don't assume
If the inside gets wet it may be their responsibility but it will be your problem
Most of them that know what they are doing will have tarps in case of heavy rain/shower
But if they have a decent crew the tar paper goes up pretty quick
And the shingling is real quick w/Pro's too
Most roofers do not tear off in the rain, but if they get a break in the weather they may tear off a section & get it prepared in short order so they can roof it. Anything relying on felt overnight I always get my guys to tarp it(stops the felt from buckling & holds the paper down better in a wind)
If they are experienced they will be quick.
DC Roofing Inc
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