This is a really old thread, but for anyone that finds this (like me), let me share my recent experience. We had an unfinished basement for 10 years. Over those years, we had seepage through the walls due to improper drainage outside (this was a brand new house). I agree with the poster above that suggests you fix your landscaping. We had spots where water was pooling, and water just...finds a way. It's what it does. Anyway, also during that time, I worked down in the basement on top of some old carpet and pad that we tore out of a room we put hardwood floors in. Never had any issue with that just sitting on the floor. We recently had our third child, and decided it was time to finish the basement. We decided that we would waterproof the north side of the house that had most of the water seepage in the past. For the flooring, we put down linoleum in the bathroom, laminate in my office, and carpet in the main part of the basement where the kids would play. Lowe's sold us on the VERY BEST (their words) carpet pad for basements. It's this newfangled crap that has a "breathable" vapor barrier. So water can escape from underneath but not penetrate through it from above. That's the claim. Well, fast forward LESS THAN ONE YEAR... The whole area where that carpet is smells musty and gross. If you are going to use a pad, DO NOT, PLEASE, GOD, DO NOT buy anything with a vapor barrier on it, even if they swear it is breathable. It may be breathable, but not enough. The crappy 6 pound rebond stuff I had sitting down there for probably 7 years never did this. The moisture from your floor needs to be able to escape, not get trapped underneath there. Lowe's is now sending out somebody to look at it, and they will decide how to handle this problem. It is going to be a huge nightmare. Even if they are super cooperative, and offer to replace everything, I still have to move all of our stuff out of there, have it all tore up, clean up whatever mess is there properly (somehow I don't think Lowe's will do this part for me), and then get it reinstalled again. From other things I have read, if you are going to put anything over top of the concrete, you shouldn't try to seal it. Walls are one thing, especially if you have functioning drain tiles that will drain the water that has nowhere to go. I'd be interested to know if anyone has opinions on the laminate I put down in my office. Underneath that is the foil covered pad, which is...a vapor barrier.. Every video you watch on the internet says this is how it's done in basements. I get stopping the vapor from hitting the laminate, but worry now that it's just trapped and will try to creep up the walls. Home ownership is so much fun!

I can answer one of my own questions after reading the DriCore FAQ. It states to not apply any waterproofing sealer to the concrete. It also makes this statement regarding tile: "Tile - DRIcore is designed to act as a floating subfloor. It is not recommended that ceramic tile be directly attached to DRIcore as the movement of the floating subfloor will cause tile and grout lines to crack. In the case of a ceramic installation, prepare concrete floor by applying liquid concrete leveling compound to the concrete floor surface to eliminate concrete floor height variances. Fasten each DRIcore panel with four, flat head and countersunk, concrete fasteners to the permanent concrete floor to prevent movement or shifting of the finished ceramic tile floor. Dab silicone in the fastener openings to seal these holes. DRIcore panels must lay perfectly flat without bounce or deflection. Install a ¼" underlayment or ½" cement board suitable for ceramic tile installations on top of DRIcore. Follow the underlayment manufacturerÂs installation guidelines for fastening to a subfloor. Please note that we also do not recommend gluing underlayments or other wood flooring materials to DRIcore. "

The IRC, if applicable, is not specific about the definition of "exposed ground". I interpret it to mean any vapor permeable surface on the ground but it doesn't say that and a slab might retard vapor somewhat. But the code also requires an unvented crawl space to have mechanical ventilation and an 18x24 access opening, so the builder owes you that in any case. The inspector owes you an explanation for why the work passed inspection not that he owes you any more than that and you shouldn't put him on the spot more than necessary to motivate him to tell the contractor he has violated the building code. the usual problem with those situations is who the inspector's relatives and friends are. I have shown some of the relevant code requirements in bold below. Italics means a term is defined elsewhere in the code. 2012 International Residential Code: SECTION R317 PROTECTION OF WOOD AND WOOD BASED PRODUCTS AGAINST DECAY R317.1 Location required. Protection of wood and wood based products from decay shall be provided in the following locations by the use of naturally durable wood or wood that is preservative-treated in accordance with AWPA U1 for the species, product, preservative and end use. Preservatives shall be listed in Section 4 of AWPA U1. 1. Wood joists or the bottom of a wood structural floor when closer than 18 inches (457 mm) or wood girders when closer than 12 inches (305 mm) to the exposed ground in crawl spaces or unexcavated area located within the periphery of the building foundation. 2. All wood framing members that rest on concrete or masonry exterior foundation walls and are less than 8 inches (203 mm) from the exposed ground. 3. Sills and sleepers on a concrete or masonry slab that is in direct contact with the ground unless separated from such slab by an impervious moisture barrier 4. The ends of wood girders entering exterior masonry or concrete walls having clearances of less than 1/2 inch (12.7 mm) on tops, sides and ends. 5. Wood siding, sheathing and wall framing on the exterior of a building having a clearance of less than 6 inches (152 mm) from the ground or less than 2 inches (51 mm) measured vertically from concrete steps, porch slabs, patio slabs, and similar horizontal surfaces exposed to the weather. 6. Wood structural members supporting moisture-permeable floors or roofs that are exposed to the weather, such as concrete or masonry slabs, unless separated from such floors or roofs by an impervious moisture barrier. 7. Wood furring strips or other wood framing members attached directly to the interior of exterior masonry walls or concrete walls below grade except where an approved vapor retarder is applied between the wall and the furring strips or framing members. ___________________ R408.3 Unvented crawl space. Ventilation openings in under-floor spaces specified in Sections R408.1 and R408.2 shall not be required where: 1. Exposed earth is covered with a continuous Class I vapor retarder. Joints of the vapor retarder shall overlap by 6 inches (152 mm) and shall be sealed or taped. The edges of the vapor retarder shall extend at least 6 inches (152 mm) up the stem wall and shall be attached and sealed to the stem wall; and 2. One of the following is provided for the under-floor space: 2.1. Continuously operated mechanical exhaust ventilation at a rate equal to 1 cubic foot per minute (0.47 L/s) for each 50 square feet (4.7m2) of crawlspace floor area, including an air pathway to the common area (such as a duct or transfer grille), and perimeter walls insulated in accordance with Section N1102.2.9 2.2. Conditioned air supply sized to deliver at a rate equal to 1 cubic foot per minute (0.47 L/s) for each 50 square feet (4.7 m2) of under-floor area, including a return air pathway to the common area (such as a duct or transfer grille), and perimeter walls insulated in accordance with Section N1102.2.9 2.3. Plenum in existing structures complying with Section M1601.5, if under-floor space is used as a plenum. R408.4 Access. Access shall be provided to all under-floor spaces. Access openings through the floor shall be a minimum of 18 inches by 24 inches (457 mm by 610 mm). Openings through a perimeter wall shall be not less than 16 inches by 24 inches (407 mm by 610 mm). When any portion of the through-wall access is below grade, an areaway not less than 16 inches by 24 inches (407 mm by 610 mm) shall be provided. The bottom of the areaway shall be below the threshold of the access opening. Through wall access openings shall not be located under a door to the residence. See Section M1305.1.4 for access requirements where mechanical equipment is located under floors. R408.5 Removal of debris.The under-floor grade shall be cleaned of all vegetation and organic material. All wood forms used for placing concrete shall be removed before a building is occupied or used for any purpose. All construction materials shall be removed before a building is occupied or used for any purpose.

"2x4 sleepers with rigid foam in between" Any wood must be on top of the XPS (extruded polystyrene) foam, otherwise moisture moving upward through the slab, or as a result of small leaks or floods, will promote mould and rot. Besides Dricore or equivalents, alternative acceptable approaches would be a layer or two of 1/2" plywood above the foam. Or a plastic air gap membrane such as Delta Fl followed, depending on the final finish, by plywood. If you are using tile or stone, no subfloor is required, though a crack isolation/prevention membrane such as Kerdi would be advisable. I have often used low-pile synthetic carpet directly on newly poured well-drained concrete with acceptable results. In all cases, mechanical dehumidification is necessary to keep rh below 50%. See Building Science Corp. publication BA0-309 for further information.