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cberes
Vaulted Ceiling Condensation

Hello,
I'm located in Appleton, WI. I have a house built in 1979, with a vaulted ceiling over my living room. The chimney box for the fireplace goes up through this ceiling/roof section. Every Spring during the first thaw, water drips down and then never again throughout the Summer months, even during heavy rains.

2x8s were used for the roof joists, the space between the insulation and the roof deck is only about an inch.
So I know for sure there is not enough room between the ceiling and roof deck to properly ventilate and insulate, especially during WI winters.
I have soffit vents in this section of roof; however, there is no ridge or pod vents. I'm sure I can install pod vents once there is enough ventilation space.

My dilemma is... how do I create a gap big enough in this ceiling so I can properly ventilate and insulate?

Advice on this would be greatly appreciated.
Thank you in advance.

Timothy Miller
Re: Vaulted Ceiling Condensation

Howdy, an inch is enough to vent the attic spaces between 2by8s. But without venting at the peak of the roof- the roof is not venting. If the roof at the peak, again has only an 1" of space you need to vent each rafter attic space. The choice is adding a vent in each space between rafters or a continuous ridge cap vent. The first thaw- is that when there is snow on the roof? How deep is it? Sounds like water is getting in around a flashing that when there is a built up of snow is higher then the rest of the year? Does the chimney have a drip collar on the vent pipe stack above the roof flashing? Consider using a 50 year caulk around the drip flashing collar to the pipe or pipe to the roof vent flashing and see if leak all gone...

cberes
Re: Vaulted Ceiling Condensation

Thank you Timothy, I will check those things out. The bad news for me is I had that section re roofed about 2 years ago.

The first thaw- is that when there is snow on the roof?
Well, there was no snow or even rain the days my ceiling dripped. In fact, the drips come on sunny days the first few weeks of Spring.
My concern is about condensation building up during the long Winter months and then melting in the Spring.
How do I keep the warm inside air from getting in contact with the cold roof deck with only 8 inches of space to insulate and yet keep ventilated?
Everything I read tells me I need a minimum of R-30 for this type of roof in Wisconsin, but it would be too thick for ventilation.

Timothy Miller
Re: Vaulted Ceiling Condensation

Howdy, if you have insulation in the attic spaces between the rafters it keeps the warm in the home and the inch is to allow for air movement from the eves vents and then out if ridge or vents near the peak of the roof. Other then adding insulation on the ceiling or on top of the roof deck there is no other way to go up to r30. The adding of a continuous ridge vent is only removing the ridge cap shingles and cutting a 1'' gap at the peak if the decking is not already spaced there and then adding the continuous ridge vent that has its own shingle included.

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