drainage system; floor to ceiling water barrier panels

[meeski]

We have an old home with a huge sandstone foundation. An addition has a concrete block foundation. We have a lot of ground water (possibly a spring), but it's impossible to do anything on the exterior of our house--only an interior french drain system. Contractors all agree two sump pumps are needed. I'm down to choosing between two companies... One says the perforated pipe should be placed directly on the clay with gravel over it; the other plans to have gravel under perforated pipe as well as around it. Are there advantages or disadvantages to each? Would the pipe (bottom is perforated) that's placed directly on the clay be susceptible to clogging??? (The company says no, and insists that more water will be moved along the pipe if it's not on the gravel.)

Each plans to cover the walls floor to ceiling with white water barrier panels. Could these barriers cause any deterioration of the walls behind the panels? (The sandstone has an incredible efflorescence problem... only one concrete block wall has efflorescence.)

There are so many different sump pumps... I haven't compared the two companies' sump pumps yet -- what important features should I look for???

This is a huge project and very expensive. Any info or cautions you can share will be greatly appreciated.

Thank you!
meeski

[ka3vvv]

I had 5 companies come out in give me price. I?m located in Delaware county Pa Sharon Hill Pa. One of them was going to do it for $38,000 He went down to $17,000 that was Met-Atlanta. What a rip off. I had basement Doctor come out they ask for $5000. Vulcan Basement won't $7500. Desert Dry won't $3000. Springfield waterproofing won?t $2000. This for 89 Linear Feet.
What it cost me to do it myself. Jack Hammer 4 hours rent $58.00. 10 yard Dumpster for a week $200. Crush stone is $22.50 a ton, I need 3 ton delivery coast $30.00. Tubing cost $27.00 for 100 ft. 5 bags of concrete @ $3.00 each. Sump pump $160 with pvc 1/2 hp etc.concrect mixer $65.00 for day
It will cost me around $544.50 in materials.
You will have to dig 12' down & 12' always from the wall so you will not hit the footer. Every 8ft you will need a 1-inch drop always to the sump pump.
I?m doing it now I'm not done yet Do a little every day after work.
It fun but lot of work.