Expert: Bruce E. Johnson - 11/24/2008

Question
I have leak in the roof over my kitchen table. It's a bump out so there's only one floor there. One company that gave me an estimate said they want to put in a ridge vent.  Is that necessary? The bump out has a vaulted ceiling. Is there really that much area above it that need to be ventilated?

Answer
Hi milo, we have been building the last two years with no attic ventilation.  To do this however you need to insulate up inside the rafters as opposed to insulating the ceiling and leaving the attic uninsulated.  The thinking is that by insulating the rafters you turn the attic into conditioned space thus eliminating the need to ventilate it because you don't get the heat build up that needs to be vented.  You also don't get the moisture transfer between hot and cold surfaces. Plus I have never been a big fan of ridge vents, period.  I live in Florida where we get wind driven rains that can easily cause a ridge vent to leak water even with a Cobra (fibermesh) insert.  So unless there is something about the construction you are not telling me I say "no" to the ridge vent.  I hope this information helps feel free to write again regarding this or other matters, sincerely bruce e johnson..bejohnsonconsulting.com