Curled shingles can be caused by ice dams or high winds, which means that your attic insulation might not be sufficient for this climate, and temperature changes could cause damage. In winter months, if it’s below 20 degrees outside there is likely enough heat in the house to prevent an ice dam from forming but as temperatures rise this becomes less of a guarantee so fireplaces should have proper ventilation installed. Also, check around any chimneys on top of the house – these vents sometimes get covered up with snow and left unblocked can pose a major problem come springtime when melting buildup goes unnoticed until cracks appear in ceilings throughout interior rooms.