Infrequenty used drains?
If you have any drains that are infrequenty used the water in the traps eventually dries out and can open a path for sewer gases to back up. You mentioned the cold (cold air is also very dry, speeding evaporation) but along with the cold has come some very windy days that can pull some water out of traps. If a drain is in occasional use, no problem, the trap fills right back up. But if it isn't used much and the trap is drying out, the wind can be the finishing touch, sloshing water out of the trap and also pushing sewer gas in when a strong gust comes along. We had a seldom used shower in the basement of a house that opened up exactly this way with the accompanying odor. The fix, pour some water in to refill the trap. If the drain is NEVER in use (like a just in case floor drain) I don't know if the sink antifreezes (NOT car) are more resistant to evaporation which would make the problem less likely to reoccur.
|