Hmmm... Nothing is insulated. I've talked to a few contractors (including a waterproofing company) and they all said to not attach anything directly to the cinderblock or else mold would grow. I was planning on traditional stud framing with insulation between the studs and stuffed in between the ceiling joists. Hadn't even considered the floor.
My sump pump runs all the time but there's nothing I can really do about it. We have a high water table plus water runs down hill from my rear neighbors into my yard. I was hoping proper sound insulation around the sump pump access would do the job.
My house is very old (100 years) but the addition where the theater will be is brand new (2 years). There are some awkward areas where old meets new but I think I can work around them (I dug down 3' in the old space to get additional ceiling height).
Anyway, I just don't know where to begin... the layout is mostly finished on paper (although I haven't even thought about equipment). Do I just order some 2x4s and get going? Heh.
Sorry I've written so much in your thread. Yes I was too paralyzed when I bought the house, always smelled some mustiness, and then later poked holes in drywall and found NO INSULATION down there. I was mad that when they'd drywalled (after prior flooding) they didn't bother. I left bad carpet down there, knowing eventually I'd lay down a sub floor of some sort (speaking of which I have a chart of
different subfloor options. It was investigating mold in walls (it had grown a foot up the walls, on the back of drywall) that forced our hand to demo. I still debated methods, but we finally got it in gear this summer/fall.
Having a spreadsheet (we used Google Drive) that we could see projected timelines with "swim lanes" for phases helped. We could see that we'd need to do this before that, and schedule that guy before that guy, and buy this stuff before we can do that part, etc.
Having a wife who doesn't procrastinate and who missed the old theater as much as I did helped too. She pushed on schedules, purchases, and finding vendors. "Go research, you have until tomorrow, and then we're pulling the trigger!"
Finding cheaper carpenters we could trust, who worked a Saturday or an occasional evening was nice. Coworkers helped out here and there with an emergency, advice, or lending tools I didn't have. I think I ended up using every single tool I had...stuff I never thought I'd actually use or need to use again.
I'm jealous you're starting with a clean slate and don't have to demolish the existing.
With high water tables, the things that people time and time again mess up and forget are:
Sump Pumps
- The sump is critical. Buy two. One of mine is a battery backup.
- The sump float switch will fail eventually. Replace them every few years. The ones with the float on a cable to the side are worse (they can get hung up or the mercury switch fails) than the vertical ones.
- Since I can't afford a sump failure in spring-summer, I'm replacing my six year old sump pump with a new one. $130-$200 good investment to be safe.
- We're supposed to run the sump water outside, not into sewer drain. But during Spring when that line could be frozen, we do send it into the sewer. It's not much water and doesn't hurt the city.
- Some people need a second sump pit in another part of their house. My boss has one in the center of his slab, too!
Grading
- So many people in my hood said in 2010 that they never flood. They didn't care about their grading. Then in 2011 record rains, their basement flooded. They admitted that they had concrete and grass lawn sloping TOWARDS the house. This seems like a pain to fix...until your theater is flooded. Fix this! Grade away from the house.
Gutters
- Send the downspots on a run down the slope (you did slope, didn't you?) 10 feet away from the house/foundation. The original excavation of your lot disturbed soil compacted over thousands of years. The backfill is never as compacted as that. Water within ten feet would rather slope down the cone towards your foundation wall. It will come in through the cove joint (between slab and footing) or through wall or just raise the water table up.
- We run the gutters into solid pipe that extends 10' away, and then into perforated pipe that runs to the sidewalk and into a gravel filled pit. Maintain slope to prevent standing water freezing in Fall or Spring.
- Fix the gutters. We had one run that was filled with tar from some past crappy roof job. Water would run out the side and plop next to the house! We got a new roof and gutters this past summer, so that problem is solved.
Drain Tile
Since you're starting new work, you could test the drain tile perhaps? Or have a plumber who's there for other work send a scope through it?
Oops Groundwater
I left a sprinkler hose on too long in the front yard the other year. We hadn't fixed our grading in that spot (and this last year saw that the mold was worst there!), and sure enough, my forgetfulness led to some water coming in through that cove joint. It's at the center of my theater front wall.
You can use timers on sprinklers. Be wary of kids, too. I also left a hose running on back bushes when I was a six year old. Flooded the storage room.
Interior Flood
I've known many people with water heater tanks that failed. Ours was starting to leak and we replaced it last year. We added a tray that drains to a hose that drains to the floor drain in the furnace room, and laundry should drain there too. The week after I replace mine, a coworker's failed just outside of the low 3 year warranty. It flooded his basement.
Technology
Besides the timers, you can use flood alarms. I have a loud sensor now, but later I'll get a Z-Wave one that would alert phones.
--
My hope would be that you can lower the water table under your house and that sump pump doesn't need to run as often. I need to add some vibration damping between PVC outlet and some framing that makes a hum when it runs. I hope you can get yours quiet so you can enjoy your movies!
Start a build thread and add some photos and we'll cheer you on out of paralysis!
