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How to insulate existing slab edge before new concrete porch – GreenBuildingAdvisor
My house is built on a slab that is uninsulated. All around the exterior of the house, it has a 6 inch wide section that is raised 4 inches above the slab that the exterior walls set on. Ive been insulating the edges of the slab a section at a time. I currently have a concrete back porch that im looking to tear up and repour. Id like to insulate the house slab edge at that time but im not sure how I should do it. For the rest of the house, ive been attaching xps foam board to the slab edge and covering it with aluminum. For the back of the house, should I do the same and just pour the porch against the xps covering? Or should I something else? Thanks.
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Replies
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Expert Member MALCOLM TAYLOR | | #1
Derek,
I’d use the same detail you have done elsewhere on the perimeter, but use a slip sheet of rigid plastic to separate the aluminum flashing from the new concrete to avoid corrosion.