Ventilation Louvres

Can I use a gable fan in an attic with ridge vents?

I have terrible moisture problems in my attic that leads to mold. I just had the roof replaced 1.5 yrs ago along with the sheathing and the mold is back. There are ridge vents and the foam pieces to hold the insulation away from the edge vents but clearly it isn't working. I am trying to decide on just trying to add gable vents or an automatic fan with humidity and temp control. The problem is, wouldn't a fan just draw air through the ridge vent area near the fan and not actually pull air through the whole attic? Should I block off the ridge vent?

Public Comments

1. Keep the ridge vent open and put the gable fan in as well. The ridge will take care of heat up at the top and the gable fans will draw air through the rest.
2. definitely don't block the ridge vent. adding a gable fan or a roof fan will help, i had to use both but no mold problems since. keep in mind a gable fan should blow to the north or west to draw in from the south or east, less moisture i think. it might be related to whole moss grows on the north side of trees thing.