Interior drain tile and finishing basement?

I bought a house 5 years ago that has an interior drain tile system in the basement and there is a 1/2″ gap around the perimeter of the wall. I am going to start finishing the basement walls in the next few weeks and am trying to determine how to handle this gap?

The walls and floor have all been painted with something (I assume Drylock but have no idea) and I am not getting any water in the basement. I will be installing rigid insulation against the foundation wall and then my studs and sheet rock over that, in accordance to the info provided on the buildingscience.com web site.

I am wondering if I should seal that gap around the perimeter of the floor and then just install the thermal break/bottom plate right over that gap?

No do not fill that gap. if water were ever to get in thru your walls going down that gap to the drain tile is neccesary. Attach poly to the block wall to act as a vapor barrier than frame your walls 2×4’s, Metal studs,etc. do your wiring,plumbing, and heating if needed than insulate with a r-11 insulation that is NOT paper backed. Sheetrock your walls and hold the sheetrock up 1/2 inch off the floor. If your floor gets wet your sheet rock will wick it up. Good Luck,Pat

Use 2×4’s and use roll insulation, that ridged stuff is trash, no R value and cold air will come in. Trust me thats how I did my last house and was mad when winter came and it was cold down stairs still.

Does the gap go all the way to the dirt below? We never put a gap in nor edge a basement floor. Sounds odd to me.

The gap goes to the rock that was placed for the interior drain tile system.

it is concrete it does shrink and expand. that first pic looks like its a box opening maybe for a drain? I still would not fill the gap. And I agree don’t use ridgid insulation use fiberglass and remember that you dont want to jam the insulation in the gap you want it to be snug. or it is not able to do the job that is needed.

Every basement that I have ever done has had somewhat of a gap. Some bigger than others, just depends on the mix the concrete workers used and how wet it was when they poured it. It is nothing to worry about. what we have always done in the past is hold the wall out a 1/2″ from the concrete wall, frame it with 2×4’s, use r-11 fiberglass insulation, and sheetrock. Hold the rock up 1/2″ off the floor to help it NOT wick any water that should be on the floor. Im not sure of your location by our local building inspector says to not use any poly/plastic for a vapor barreir. All it does is trap the moister inbetween the sheetrock and the outside of the concrete. As long as the outside of the concrete has the tar, water barrier or they have dry lok on the inside that is all you need. That is what we have been told the last year or so.

Any other questions feel free to hollar