Hi illinigirl, The standard insulation used under basement floors is rigid insulation (XPS -- extruded polystrene). It comes in 2 inch thick often blue pieces of styrofoam. Dow manufacturers it among others. It is not spray foam. We used it in our build -- we are in southern Canada. The labour to lay the rigid insulation sheets was not high. The guys had to dig away a bit more gravel so the basement ceiling level was not compromised. They used the red tuck tape to attach the sheets to each other. This allowed the concrete flat workers to pour the floor with wheel barrow loads. I am not sure yet what a difference it will make as we are partway through our build. We have hydronic in-floor heat that was just turned on for the basement level. The floor is wonderfully warm (mostly due to the in-floor coils). We were required by code to place the rigid insulation because of our planned in-floor heat. Otherwise, I understand, the heat from the coils would not just heat upwards and instead would have been wasted heating underground? We did place the rigid insulation around the perimeter of our our unheated garage. I will go and step on the parts of the garage floor that have the insulation vs the parts that don't to see if I can detect a big difference and report back. Our architect spec'd for this rigid insulation under the basement slab. At the time, we had not planned for the in-floor heat. In other words, he felt it was a good practice even without in floor. The rigid insulation sheets are not cheap. We paid $25.00 a sheet (each one is 2 feet by 8 feet). We are in Canada where everything seems pricier. You can calculate the area needing coverage and see how much your builder is charging for labour vs material to help you decide if the price is reasonable. Don't forget the tack tape is also not cheap. Best of luck. Carol

Hello, we are currently going through much of the same. We have a 70s' tri-level with lower level family room that had carpet until the rain seepage ruined it. After installing a second sump pump in the crawl space, we ripped up carpet and soaked pad along with the lovely orange tiles below. We've decided to replace carpet with 18x18 ceramic tiles, although we were also looking at a product called duraceramic which is warmer on the feet because only the top layer is ceramic. It also has acrylic grout instead of sanded which is easier to keep clean. They also make this in a wood look. It's a little cheaper than ceramic but my husband said if we want ceramic we should buy the real thing. I asked the friend we're buying new ceramic from if we could have had asbestos. He said if the tiles were smaller than 12x12 they probably were, but ours weren't. Good Luck!

Yes, you can insulate between your floor joists, but ..... it's not the most cost-effective first insulation project if you're starting from no insulation. The best is the attic, and then make a huge effort to seal up air infiltration throughout the house (caulking, mostly). But you have another problem with your basment (aside from the squirrely foundation issues) and that's moisture vapor rising from the dirt. That you interupt with a good moisture retardant material laid directly on the dirt and well sealed at the foundation. You could also do an air infiltration barrier under the floor (without moisture control); staple it just under your joists it will help prevent cold air getting into your living space. It doesn't insulate, just blocks pressurized air from coming up. But I wouldn't do that until you had blocked moisture vapor at the soil level. The insulate the walls (of the cellar) first recommendation may not really apply to your situation, and anyway I have read here some comments suggesting that it might do some damage. (I have no opinion about that, I'm just passing info I've seen here.) But first, you need to get the bulge/settling problem sorted out and at least know what you must do. After that you can decide whether that project is going to happen soon, or will be put off indefinitely. Then it would be time to decide what else you want to do in that space: Moisture barrier on soil, infiltration barrier under joists and/or insulation between joists. If you chose to do it all, I would square away any electrical or plumbing changes (including insulating any water/drain pipes), insulate between joists, install air infiltration barrier and finally install the moisture barrier on the floor. In addition you need to think through your furnace/boiler arrangements. You may need to insulate the pipes or air ducts, as well. If you create a thermal break between the unheated cellar and the heated living space, you can create problem with your heating plant. I have no advice there as I don't have central heating. If you're just "itching" (LOL) to get some insulation installed, do the attic first, and soon, as the temps up there will get unbelieveable in just a few weeks. Or you could take a wait and see approach and resign yourself to having not the most energy efficient house while you experience a full year's life in the building and can make better choices based on what find. There's good counsel in taking a go-slow approach to old house care. Less of a risk of an inadvertent bad choice. BTW: my personal choice for between the joist insulation is rigid foam sheets. Molly~

Alisande, we have a damp basement, too, and, like you said it's a pain to empty it. We have to empty it about twice a day in the wet season. As you might imagine, we're really tired of doing this! We wish we had a floor drain to have it empty into, but we don't since it's an old house. What we're going to try to do--and maybe you can do this, too--is figure out how to get the dehumidifier drain into the laundry sink. In our case, we need to rig some sort of hose for it and figure out a way to raise the dehumidifier to the proper height. But maybe you don't have a sink in your basement... :( Even so, a dehumidifier is worth having. We got ours at Lowes for about $120 and it has been money very well spent. Our basement smells clean and nice, and the items we store down there don't get damp like they did before we were running the dehumidifier. Of course, a dehumidifier can't solve all moisture problems. It definitely sounds like your gutters/etc were causing the problems. You might want to take a look at some books on basement moisture problems. Right now, I have two books out of the library on this subject that are really helping us figure out how to make some simple fixes without calling in the professionals. Home Water and Moisture Problems: Prevention and Solutions by Gary Branson (this one is so good that I'm planning on buying it for friends and family for Christmas!) 5 Steps to a Dry Basement or Crawl Space by Ronald K. Gay I sure hope some of this info is useful. I know how annoying it is to have a wet basement. Good luck!