Hello. I’ve been reading your site and forums off and on for years. Mostly regarding basements. I’m in need of a sounding board.

My home was built in 1982 in northeastern Maryland. A 36×30 walk out foundation. I know the slab does not have poly sheeting or insulation below. The block wall has visible tar treatment below grade. Approximately 60% of the perimeter is below grade or transitioning to grade for the back door.

I demolished what was finished basement. Before it could be rebuilt I noticed significant water intrusion under the block. We brought in the local franchise of one of the basement companies to do an interior drain to sump and foiled bubble wrap / reinforced poly sheet on the affected walls. The air quality is remarkably better.

The main space in the basement is the largest room in the house at 11×23. It has been an entertainment and hangout space with TV and multiple computers. I want it to be again. However I seem somewhat limited on height.

Slab to joist measures 93.5”. Slab to lowest HVAC in main room, a supply trunk, is only 84”. The other ducting, a return box and six 6” supplies, are only a couple inches higher and kind of all over the place. There’s just too much ducting to bulkhead. 

Complicating matters, the nearby powder room toilet is already on a diy tile riser. Another adjacent room features the walk out doors and a stove to burn wood or coal resulting in a fair amount of dust. I don’t want to invest in nice flooring that will get scratched up. Can’t raise floor level too high because of the toilet and swinging entry doors. Could only tile the stove room because of embers. 

I have flirted with replacing the furnace with high velocity to eliminate the obnoxious ducting. The current system was not designed for air conditioning and we’ve always had severe temperature differences between floors.

Am I correct in assuming that I don’t have the height to replace the suspended ceiling? I also don’t have the height to consider insulating the slab for comfort?

The latest idea I’ve had is to not rebuild the walls or ceiling. I don’t think home theater style acoustic treatments like curtains, clouds, baffles, or absorber panels are covered by code so their heights are irrelevant, right?

I’d be very grateful for any opinions.