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I am adding a room to my home, the contractor poured a concrete slab for the addition and it slopes toward the existing house and it is now raining and water is coming under my floors. Is the slope of the poured slab correct?

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you have a problem. Without drainage, you will be in for some rot – shirlock homes Mar 20 '13 at 23:00
Bring in an inspector for a third party opinion, then when he confirms that you are being scammed I would kick the guy off the project and find someone else to fix it correctly. I have seen too often where ignorant contractors can ruin lives. YOU WILL THANK YOURSELF LATER! – maple_shaft Mar 21 '13 at 9:01

The slab upon which the addition is to be built should normally be level and without a slope to it - (a garage floor may be different). In addition the final grading of any surrounding dirt coming up to the slab/foundation should be BELOW the slab level and should slope away and down as it gets farther from the edge of the new house line.

The contractor that placed the slab is probably the wrong person to be getting assurances from regarding whether the non-level slab is OK. If they messed up the slab they are probably going to try to convince you that it is OK and try to proceed to build on top of it!! Get a formal opinion from 3rd party or your building inspector.

During the construction phase a new addition slab that is built up even with an existing floor line is likely to be susceptible to rain water coming in under the existing wall base plates even when the slab would be level. A good contractor would probably make allowances to place plastic up on the existing outside walls that drapes down over the new slab and out some 6 to 10 feet to help keep rain water from collecting up near the place where the new slab joins up against the existing wall area. If your slab with it's slope toward the existing house is a legitimate design then it seems to me that such temporary measure may be even more important. However I suspect that the slope is completely improper in this case for a bedroom addition and the fact that the contractor did not take steps to keep rain water from running into your house speaks volumes about the poor quality of the workmanship being done on your project.

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NO!......... NO!.......... did I say NO?

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As the funny papers would put it, "No way in flaming @$$%#!!" – Fiasco Labs Mar 20 '13 at 23:54

Generally speaking, the slope of anything involving a house should be away from the house. However, every situation is different, so it's a little difficult to say for sure that this is wrong.

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They will be adding sf to my bedroom on this particular portion of the concrete slab and the general contractor tells me it is ok? but is it? – dysauseda Mar 20 '13 at 23:08
Again, at a very high level, you do not want water in certain places, inside a house is one of them. Without any more details, no, I'd say this is not ok, but again, we're not there to examine the details. – Aaron Mar 20 '13 at 23:25

If this is a slab floor for living space, it should be level with no slope at all (strike one for the contractor).

If it's the floor for a garage area, there can be a gentle slope towards the car entry door (strike two for the contractor).

Otherwise, if it's intended that this is an outdoor floor area, it should be sloped for drainage away from the house (strike three for the contractor).

End of inning, cement subcontractor couldn't be bothered to float the surface and level it for a floor in a room, hire a new team.

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