# insulating drop soffit on exterior wall



## Windows on Wash (Aug 30, 2011)

Best way is to cover the drop soffit with a rigid foam and air seal it. 

Then bring additional insulation over the top of the foam board and make sure that the ventilation is proper and continuous.

https://basc.pnnl.gov/resource-guid...attic#block-views-guide-static-blocks-block-2


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## JonkL (May 31, 2015)

Thank you. I had found that website last night, but was a little confused. in our situation, the roof line comes down at such an angle we wouldn't be able to insulate on top of the foam board you cant even get close enough from the attic side to see into the soffit. i understand that the warm air is flowing up thru the soffit and coming in contact with the roof sheathing and the back side of the facia board, creating condensation. currently there is the batt insulation in the soffit cavity. is this o.k? since we have water damage in this area, I would like to open the soffit to make sure there is not any mold growing.. should the soffit cavity be void of all insulation? do i put the foam board on the top of the soffit- from the underside, since that is the only way i can get to it, and also on the back side of the face board? or do I just put plastic sheathing in that area? can i/should i keep insulation in the soffit cavity? sorry no picture, no digital camera right now. Thanks!


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## Windows on Wash (Aug 30, 2011)

If the clearance is tight, layer the foam board until you get a suitable R-Value in the assembly.


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