Help, finishing basement

[MW]

What a can of worms this is becoming. We are going to finish our 45- yr-old basement, and so far, 6 contractors have 6 different ways of dealing with our moisture problem.

All around the bottom-most foot or so of the cinder block walls of the basement, the old paint (I assume its Drylok) is falling off and there is efflouresence too. There is no damp or musty smell, but I know it's humid down there. Even now, in the winter, it's 60% humidity. We have never, in 3 1/2 years, had actual water come into the basement, just this seeping moisture. We have heavy clay soils.

I am afraid what will happen when we put walls up. Everywhere I go, there is contradicting information, from professionals everywhere: put up poly, don't put up poly, use wood studs, use steel studs, use insulation, don't insulate, etc etc etc.....It's enough to drive me batty. I am determined to do this, but don't want to spend $30K just to have to tear it all out in a few years due to mold/moisture. And digging up around the outside of the foundation is too costly for us, probably $60K. The moisture-proofing contractor insists we'll be sorry if we don't break through the basement floor all around the perimeter of the basement and install french drains for the water to go from inside the cinder block walls. This for $6500 on top of the cost of finishing the basement. I may be misguided, but I don't feel comfortable hacking into the foundation.

This may be a really crazy idea, but has anyone invented a way of drilling a hole in the lower cinder blocks, let all the water drain out, and then filling in all the blocks' spaces with some kind of filler/expanding stuff to keep the water pressure from filling them up in the first place?

So what should we do, Drylok + wood studs + drywall + dehumidifier? Drylok+wood+poly+drywall? I have also read mixed reviews on the mold-resistant drywall, should we use that? Help me, I am losing my mind because everywhere I go I get different answers.

[marson]

Well if you want another 20 or so opionions pulled out of a hat, you've come to the right place. I can definitively say that if you finish your basement, you are taking a risk no matter what anyone says. Some basements just shouldn't be finished. I'm not saying yours is or not, but be aware you are taking a risk.

I really doubt that the lower course of blocks is actually full of water. If that were the case, you would have water running on the floor, which say you don't have. Forget about knocking holes in the block. Your not going to stop this dampness problem with any kind of coatings.

If you really don't have trouble with running water, it's hard to see the value of running a perimeter drain on the inside. This would not harm your foundation, but it's hard to see the value of spending 6500 on this. If you were going to install a perimeter drain, you'd need to have it on the outside, which you've ruled out.

Other people will say it, so I might as well be the first: check your landscaping. Keep gutters and downspouts working. Wet clay soils are tough to deal with.

As for what you use for framing etc, I am of the opinion that you shouldn't put anything against the block that provides an environment for mold, even with a poly vapor barrier against the block. No wood, no fiberglass insulation. I finished my basement by fastening 2" rigid foam to the block with a 1x3 furring strip on top of the foam anchored with a 4" tapcon. Then regular drywall on top of that. Let 'er get damp behind the foam is my opinion, but this is my own house, and if it doesn't work, I'll just tear it out and redo. Time will tell whether I did the right thing or not.

[Joseph Meehan]

There are two kinds of moisture problems, external and internal.

Internal is just the moisture in the are condensing on the cooler walls. (Tape some foil or plastic to the wall. If it ends up wet on top, it is internal, if it is only wet towards the wall it is external. It may be both.

External problems should be addressed for outside. That is where the problem is. You get water away from the wall first, and make sure there is some sort of drain around the outside.

Each case is different so the correct solution for me is not likely to be the correct solution for you. There are a couple of general comments that should help you rule out some contractors.

If the water is coming in from the outside and they want to "waterproof" your walls from the inside, just laugh at them and send them on their way. If they are offering something quick and cheap, forget them.

[Ivan Vegvary]

As to "hacking into

Not in most basements that I have seen and designed. In my last house the basement walls sat on 12" thick footings that extended 5 feet horizontally (all around) into the basement. The four inch slab was poured on top of the footings. Jack hammering through those footings and re-bar would totally undermine the stabilty of the basement walls.

Ivan Vegvary

[moldshield.1]

Mycodyne can be applied to the concrete walls. the walls are sweating and moist due to the high humidity. get some dehumidifiers down there. Treat the concrete walls and any areas you build new walls. this will prevent mold and give you a 25 year warranty. Only costs .

40 cents a square foot and you can do it yourself to save more money. And yes use the mold resistant products out there. Nu-wol insulation and the mold resistant drywall.

Mold Shield LLC

[tksirius]

Well your going to get more opinions here....

Moisture is your problem. Dehumidifiers will always be the answer. Scrap the french drains.

In terms of finishing off the walls, thats a tricky one. There are a few ways. Drywall is cheap in materials and they do make mold resistant ones out there now. I used greenboard on all the outer walls a regular drywall on the ceiling.

There are basement finishing systems out there too. They are sort of like removable panels on the walls. Looks ok but I do love the idea that you can easily go behind the walls if you had to by just removing a section.

Your budget is going to determine the type of job you want to do. G o with the contractor that you feel comfortable with. I personally wouldnt be into guys trying to dig up the outside nor inside of the house.

Tom