Exterior basement membrane and insulation order
Hi all,
I am looking into installing insulation and a dimple membrane on the exterior of my basement soon. It will flow down to an existing drain system that is at the exterior footing. I am curious in what order it recommended in my situation considering I see some recommend the dimple over concrete then a the rigid insulation on top and others the opposite.
I am in zone 7 in Northern Minnesota. My water table is pretty high, even during weeks with minimal rainfall my sump pump runs every couple days (previous owners installed a decent drain system at the exterior footing.
I desperately need insulation down there so I want to install a dimple membrane while I have things dug up.
My concern with the membrane first method is the possibility of the insulation becoming highly saturated due to the water table being so high and then reducing my insulation efficiency.
Thanks a bunch!
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Replies
Night_Wolf,
Here is what Martin said in his blog on the subject:
"What if I want to install exterior rigid foam? If your foundation includes exterior rigid foam, a question arises: Does the dimple mat go between the rigid foam and the concrete, or on the exterior side of the rigid foam? Experts provide conflicting advice. The choice is yours."
https://www.greenbuildingadvisor.com/article/using-a-dimple-mat-to-keep-a-basement-wall-dry