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helpingdad
January 1st, 2009, 10:24 AM
I am in the process of updating my father in-law's 80 year-old home. He's a great guy, WWII decorated vet, and the home is his only asset. My budget is limited but my wife and I are determined to make the house saleable and provide him with much-needed funds. Until my rehab began 2 years ago, the home had almost no updates. We've completed 100% replacement of all upstairs plumbing, electrical, added a bathroom, furnace, and many other updates and improvements.

Now we are addressing the biggest problem - the basement. The basement ceiling was maybe 6'2" at the high point, the floor was heaving from hydrostatic pressure, was cracked in several places, no floor drains existed, and water leaked profusely from every wall. With allot of help from friends and relatives, we broke up and removed the entire basement floor and I will replace the concrete, add drain tile, sump well, and floor drains. I've already poured new footers for the beam posts and replaced the original rotted wood posts. The substrate is mostly sand with clay at 12 - 24 inches below grade.

I need help with plans for the poured concrete floor and drain tile layout. The tile will be place at the base of all 4 interior walls and fed into a sump well at the back of the house. The basement measures approximately 20' x 30'. I have some questions and issues:

1. Without my supervision, overly zealous relatives, preparing for drain tile installation, removed too much soil at the base of the wall footer on 2 walls. They dug down at least 18" below the bottom of the footer. The walls seem stable but some underpinning soil has eroded with water infiltration. How do I repair/stabilize those walls? I'm assuming that I want to stay outside a 45 degree angle from the bottom of the footer.
2. Where is the ideal placement of the tile? How far away from the footing? How deep?
3. What type of tile should I use - slotted corrugated, perforated solid coex,??
4. What slope should I use for the tile - is 1/8" per ft OK??
5. Should I add a tile branch across the middle of the floor from corner to corner? When I dug the footers for the new beam posts in the middle of the floor, I was getting water at 12” below grade.
6. The floor will be poured by a cement contractor (neighbor) who is helping us our. Can we pour the new floor so that top surface is even with the top of the footer? This would give us approximately 6'5" height between the floor and the ceiling joist at the walls. We will slope the floor toward the center of the basement where the new floor drains will be placed.
7. What size pipe should I use for the floor drains? I will pipe 2 drains using PVC and empty to the sump well.

I really appreciate any help you can provide. I am usually the first to hire professional contractors when I'm not qualified to handle a DYI project but I'm buried on this one. I don't have the money to bring in anybody right now and we're trying to help out my father in-law as much as possible. Thanks again!!

helpingdad
January 2nd, 2009, 04:11 PM
I want add a couple of additional of things. Thanks in advance for your help.

1. I want to use just one rock type as base for the new concrete floor and as base and cover for the drain tile. Any suggestions? My concrete contractor neighbor suggested pea stone/gravel and my local concrete/aggregate supplier suggested 6A Stone (Washed 1/4"- 1").
2. I had the suggestion that I use some sort of water-channeling panel at the base of the wall and the new floor. I'm assuming that these panels would be placed to catch water seepage where the poured basement wall meets the floor. I've seen various panels profiled on some of the waterproofing products websites. Do they work? What would you guys suggest? Where are they placed exactly?

As a note, the drains I will place will be located in the new laundry and work rooms. They are intended for overflow accidents from sinks that will be placed in both of those rooms. The drains are not intended for water seepage not caught by the drain tile.

Thanks again for all the input. You guys are helping allot.

Wgoodrich
January 5th, 2009, 06:03 PM
Helping dad, you have quite a project going. Suspect that it started simple but the deeper you got into it the deeper you had to go. There are answers to your quest. Now before we start to help solve your problems I ask that you copy both posts and post them in the Existing Building section of the forum. This is one where a lot of information will be produced that can help many others working or about to work in this same subject. The plumbing section if we work here will hide our discussions from many needing the same information. If you will repost in the section for building now before we start I believe many more will be served. I will watch for your post there.

It is not an impossible challenge but will take much skill to succeed for you. We will help you best we can.

Wg

helpingdad
January 6th, 2009, 06:14 AM
Thanks Wg. I'm posting in that forum right now.