So... After my kitchen renovation threads and backyard and deck projects, MrsSal and I are about to start renovating the basement.
Our house is a single family home, ranch style, from the late 50s or early 60s.
We have cinder block basement in Central PA. As far I know, we don't have water problems in the basement. We have a french drain in the basement in its perimeter or at least 2 walls connected to a sump pump.
Yesterday this happened:
We got a good deal for it saving us almost 60% on the insulation in rigid foam... this is 2" XPS. Even though it's reclaimed, it's in very good condition actually... and the guy was nice we gave us an extra 8-10 boards. All in all about 14$ per the equivalent 4x8 xps sheet.
Now my question is on how to structure the outer walls of the basement. I have researched for so many hours and there is so much conflicting information it's hard to decide on what...
Ive seen people recommend moisture barriers, others saying they dont have a place in basements... others for vapour barrier others not for it...
My idea was to put the XPS foam against the cinder blocks and tape the seams with a good quality tape. As far I was able to see, because I have 2'' panels I shouldn't need a moisture barrier since the XPS at 2 inches acts itself as a moisture barrier. Then, on top of XPS just build the walls with studs, perhaps add extra insulation such as rockwool or just leave the gaps empty and apply a vapor barrier and then drywall.
My concern is with the application of the XPS and the french drain at the edge... i do have cinder block so there are grooves in them although staggered... would this be enough if water comes in, to slide all the way down the wall to the french drain? Or, should I use some sort of dimple mat between the XPS and the cinder blocks? If I were to do the whole wall, this would get expensive... 1000$ just for dimple mat... I have seen someone recommend, to just apply dimple mat the first 6 inches from the floor in order to make sure the french drain entry is open...
Also, should I use Drylok paint on the cinderblocks? My wife says her mothers basement used to leak a lot! and once they did the Drylok paint all issues were gone... again, online I have seen contradicting information about the use of this... granted, we don;t have a wet problem basement ... sure it's a bit damp but i dont see any runoffs, however I will be doing the plastic sheeting taped to walls test in order to assess moisture. Our ground is sloped away the building for the most part, our gutters are working correctly and we do have the french drain sump pump as well ... no idea how the exterior foundation looks like in terms of french drain, gravel stones or any waterproofing... its a 50s-60s house.
Any feedback and advices would be greatly appreciated!
Thanks