Compressible gasket under car decking
I’m working on a house where the roof will be exposed glulam beams with tongue and groove car decking as the finished surface. The car decking will extend continuously beyond the wall and become the soffit for the overhang. I’m concerned about air-sealing between the car decking and the top plate.
I was thinking that some kind of compressible gasket or foam would be able to compress into the chamfered “v” shaped sections of the car decking.
Is there a specific product that would work for this?
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Replies
Daniel,
That sounds like a tough detail to air seal. I really wish they taught architects and designers about air barriers in architectural school. By the time the plans get handed to the builders, it's often too late to come up with a solution.
Daniel,
There are really too many problems on this application. The car decking needs to be cut and tapped to the timber at the exterior timber center. The tape goes from a membrane overlay that spans the top of the car decking and down to the timber. Siga Rissan 150 (6") tape will do it. This "cut" is at the exterior of the condition space before the exterior soffit begins.
My 2nd floor system is car decking on heavy timer. It moves throughout the year. The air barrier needs to be flexible and able to continually move for years to come. Drilling the joints and filling with foam is not going to do it. If we want car decking and timber in efficient buildings, we have to accept that the look requires the car decking to be segmented to allow an air barrier.