[david palumbo]

we have standard ridge vent, cathedral ceilings and want to install soffit venting. Our eves are a four foot overhang. the question is how much soffit venting do we need. Can we install vented soffit to cover the entire four foot overhang or will this be too much and effect the venting.

 

[Gary in WA]

Welcome to the forum!

Ridge vents come in different NFVA per manufacturer: http://www.inspectapedia.com/interiors/atticcond10.htm
You need to find the NFVA of the ridge to figure the NFVA of the soffit vents (one in every bay) and closest to the fascia board away from the house for best air flow, pp 616: http://books.google.com/books?id=Z8apR1RkUHUC&pg=PA606&dq=attic+airflow+with+gable+vents&lr=&as_brr=3&cd=13#v=onepage&q=attic%20airflow%20with%20gable%20vents&f=false

You don’t want the vents to and from the house, rather, perpendicular to the house.
I hope you used baffles to create an air channel all the way to the ridge leaving only 1” gaps abutting them: http://www.bergerbuildingproducts.com/productsAccuvent.html

Will you be using ADA on the drywall? http://www.buildingscience.com/documents/information-sheets/air-barriers-airtight-drywall-approach/

Where are you located?

Gary