DMX air gap on basement addition exterior walls
I have a 1950’s rambler with an interior drainage system leading to a sump. The system works fine. I am adding an addition onto the house which will be lower than the current basement. The hole is dug, concrete block walls are up, drain tile and pea rock is in place. It has not been back filled.
I plan on coating the exterior block with asphalt based tar and also using DMX air gap Which is a dimple board only on the new addition walls up where it will overlap the old foundation walls by about a foot and will terminate. The dimple board will also cover the footing and terminate near the drain tile.
How can I seal the vertical edges of the dimple board? And, is there anything else I could be doing to prevent any water issues? Or should I be placing 2” eps insulation boards on the wall instead of the dimple board?
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Jeremiah,
DMX makes a Flextrim piece for finishing the edge. The installation manual suggests applying caulk under the mat and installing the trim with fasteners.
On the question of foam, we need to know your climate zone to comment on whether two inches is sufficient. That said, you can install foam on the inside or outside, but it needs to be applied to the foundation wall to be effective. See https://www.greenbuildingadvisor.com/article/how-to-insulate-a-basement-wall for more information.
I’ve been trying to find the flex trim and haven’t had any luck. I live in southern Minnesota and purchased the dmx from Menards.
I will have extra air gap so I’ve been debating cutting the top portion off while leaving some of the dimple board and using that in place of the flex trim on the vertical edges.
I would call the support line. If DMX's trim isn't available, I would ask if Delta Mold or some other product could be used in its place.