Poor Exterior Stair Water Drainage
Poor planning will lead to water drainage problems. Slope the walkways, deck and landings away from the building and stairways.
Try to slope the concrete sidewalks and driveways at least 1/4 inch per foot away from areas in the direction of a drain leading to the street or to approved municipal water drainage systems.
In this illustration the concrete walkway is level or perfectly flat and this isn't good either, because water could sit here for long periods of time, depending upon how much slope the rest of the walkway has. For example, if you have a level area near the base of a set of stairs and a raised area about 5 feet away that is no more than a quarter of an inch high, then you could end up with a quarter of an inch thick pool of water in the area between the base of the stairs and the raised area.
In this example the concrete walkway is sloping away from the base of the
stairs, allowing all water to drain safely away and would be an excellent
example for do-it-yourselfers on how to keep water away from exterior stairs
and preventing additional water damage to other parts of the stairway.
It will also be important to make sure the other parts of the walkway also are sloped and draining away from the building. In other words, you can't just slope something about 10 feet away from a stairway, without any place for the water to drain safely.
I've seen walkways slope away from stairs in a short distance, only to have the walkway start climbing up for a certain distance, preventing water to drain away safely and in most cases create little ponds for people to walk through when it's raining. This is where planning and proper design can make a big difference, especially when it comes to site drainage.
Even though this example is a little extreme, it provides you with a better understanding of what's actually going on in the first picture at the top of the page. In some cases, it's going to be difficult to slope a walkway away from a building or set of stairs and if this is the case, then it wouldn't be a bad idea to think about installing some type of drainage pipes, before pouring any concrete.