Hi,

I want to pour a 3' x 40' slab against one wall of my house as a rain runoff barrier. I have it set to slope 1.5" over the 3'. The wall of the house is stucco so I only have a frame around 3 sides (the outside and 2 ends). I have a chalk line on the stucco . Here is my problem/question. How can I make the concrete follow the chalk line? Sounds simple but I assume that the line will get smeared away. Has anyone dealt with this situation? If the slab had a frame on all 4 sides it would be fairly straightforward to use a straight edge to get the desired slope. I'm having the concrete brought in so there will not be a whole lot of time as compared to mixing it myself.

Ian

This is not the greatest solution to your problem and may cause new problems. You should not pour concrete up againist the stucco. There will not be a water tight seal and the two materials will move at different rates as the weather changes. You could have the 40' graded and put down a membrane that will deflect the water. If you are stuck on the concrete idea it will not be hard to get the concrete to follow the chalk line. You can trowel the concrete up to the chalk, its very elastic.

ballengerb1 thanks for responding. My rain problem results from very hard rains driven by strong wind. So much water strikes the wall that the a hydrostatic head is built up and water works its way under the stucco and past the 2"x6" base beam that the walls are built on. This is a rare but unpleasant occurrence. The house floor is a slab as you probably have guessed. I was going to seal between the stucco and the slab with outdoor caulking. I do appreciate your comments about differential movement of the stucco and the concrete. Your cautions noted, I'll try the concrete route.

Perhaps all you need to do is seal the stucco against the rain. This website offers products. Unfortunately I have not tried their products yet and can't offer further advice.

http://www.radonseal.com/