Marty writes from Bethesda, Maryland: "I have a cottage-style (w dormers) house from 1948 that I'm adding additional attic insulation. I'm intending to add R30 unfaced perpendicular to the existing insulation. In doing this I'm adding rafter baffles. However, the rafter baffles don't reach the soffit vents since the distance from the intersection of the attic floor and roof line to the soffits is at least 12 ft. I plan to link the rafter vents together to get air from the soffit up to the attic. And then add faced insulation (it will have to be R-19 since the cavity is only 5 and 1/2 deep).

My question is, can I link the rafter baffles together to form a continuous channel for air to the attic or do I have to leave a 2" gap between each baffle?

I have a roof-ridge vent and two side vents in the attic. Is this alone sufficient?

Also, for some reason the former owner has the original fiberglass insulation with the Kraft paper facing down. I'm thinking about just flipping it over before I put in the R30 layer."

Answer: You need to leave 2" spaces between adjacent baffles or moisture could build up and run down causing a possible leak. There should be no need to extend the length of the baffles since their purpose is to provide a clear path past the insulation. Without the baffles, insulation could get blown or pushed too close to the roof deck and block the flow of ventilation. There is information on the Owens Corning website about installing raft-R-mate® attic rafter vents.

There is also information on the website that will help you determine the amount of ventilation you need. You should leave the insulation as it was installed. The vapor retarder should be on the warm side of the insulation in winter, which means in your case it should be facing down.