My house was built in 1950, and in my crawlspace, I have vents covered with mesh wire that circulate air to the outside.
I've been reading online that its now best practice to seal the vents in the winter, and open them up in the summer, but I wanted to get peoples feedback on this, given the environment my house resides in.
I live in a typical Northern California climate that experiences moderate weather all year around. In the winter, occasional rain storms, with the temperature approaching, but rarely hitting freezing, and in the summer, temperatures between 80-90, rarely hitting the 100s.
Throughout the year, unless its raining or foggy, humidity is never very high.
In addition, I have a sump pump in my crawlspace, as I experience a good rush of water from the hill I'm on during a downpour. The crawlspace is rat-proofed, and over time, I do need to epoxy paint over the cracks that develop that leak water to the unfinished floor (its just epoxyed-over concrete) at the end of each rainy season. This water that may escape through the cracks that develop finds its way to a drain in the concrete floor that drains to the same reservoir that the sump-pump feeds off.
Given these conditions, is it advised to regularly open/close the vents, seasonally or otherwise, for insulation or other reasons?