Soffit venting
#1
06-04-13, 01:32 PM
Soffit venting
When installing soffit vents to make use of the ridge vent we have, should the slits in the soffit vents face towards the house or away. Or does it matter?
Thank you
Thank you
#2
06-04-13, 01:38 PM
Group Moderator
Interesting question; I had to go look at mine to see what they look like. Mine are non-directional, so no help to compare. My inclination would be to face them out, but let's wait and see what one of the pros has to say. 
#3
06-04-13, 01:55 PM
Group Moderator
Not a pro, but I would face them towards the house. They will look better, similar to a return air vent facing the floor on an HVAC system. I don't think it will affect the airflow to the attic either direction.
#4
06-04-13, 04:17 PM
Under natural pressures the air flow is so slow it doesn't matter. However, wind driven ventilation can be good or bad. It can greatly increase the air exchange, but includes the risk of moisture being carried in. On average, facing out will pose little risk and improve your ventilation. But, if you have steady moist air, say fog off the ocean, then face them inward to reduce the risk. Light fluffy snow can also follow a stream of air and accumulate to some scary amounts. First hand experience.
I checked your location and it doesn't look like snow is a big concern, MS.
Since you probably use air conditioning, how much vent area (NFA) do you have high vs low?
Bud
I checked your location and it doesn't look like snow is a big concern, MS.
Since you probably use air conditioning, how much vent area (NFA) do you have high vs low?
Bud
#5
06-04-13, 04:19 PM
Group Moderator
I agree with Tolyn... if the louvers are parallel with the house, you install them so that you can't see straight up into the soffit, just like a cold air return in the baseboard... so that you can't see straight into the ductwork.
#7
06-05-13, 06:56 AM
NFA means Net Free Area. All vents have that on the packaging somewhere. It's basically the amount of open area to allow airflow. If it was a vent with a single louver 1/2" wide by 12" long it would have an NFA of about 6 sq in.
You want your intake to be at least as big as the exhaust or bigger.
You want your intake to be at least as big as the exhaust or bigger.
