I don't know how long ago this roof was shingled, but we've noticed that the asphalt shingles, in two patches, have begun to curl and lose their grit.
Even after a late summer of fierce rain, at least for now, there is no evidence of water infiltration within the home (no mould, staining, drooping drywall, bubbling paint, etc).
How long can we wait until replacing the roof? Given the budget, should it be done urgently?
If it is necessary, but we can't get it done before the snow falls (which will be soon) are there any stop-gap measures we could try?