I am building new below-grade, exterior stairs to my basement and haven’t figured out how to drain off the rain water that comes down the stairs. One option would be to install a floor drain and drain it to a gravel bed under the stairs. Since the soil under the proposed gravel bed is clay, this option probably would not work well if the rain quantity is significant. Another option would be to tie the floor drain into the house sewer line but the plumbing code might not allow that, and if it did, it would involve trenching the basement floor twenty feet. A third option would be to run a drain out to the street curb but that would require trenching fifty-five feet of garage floor and driveway. A fourth option would be to install a sump pump in the landing at the bottom of the exterior stairs where it might freeze in the winter. What would you do?
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My choice would be the gravel bed with a drain under the basement floor to a sump. That way the pump is inside the house.
Good idea! I think I will put a floor drain in the landing and run the drain pipe to a sump and pump located in the basement nearby.
A small shed roof addition to keep the rain out of the stairway? water is always best to be dealt with at the earliest point that it can be intercepted, all you have to do is figure a way to make it look like it belongs there.
Dan
A Bilco door!!??
Mr T
Do not try this at home!
I am an Experienced Professional!
Make sure you put in a trench drain! A regular floor drain clogs very easly. Is there a footer drain outside the foundation? If so tie into that.
Tim
Thanks for suggesting a trench drain. I hadn't thought of that but will now investigate that possible solution. I can't tie the drain into the footing drain because the footing drain is higher than the area at the bottom of the new stairs. I will run the drain line to the sewer if code permits or to a new sump pump if not.
You need to shelter the stairwell from the elements so that you'll have nothing to drain at the bottom landing. Two basic ways to do this:
1. If the stairwell will only be used occasionally, like as an emergency exit to meet code, build a small shed right over it sloping away from the house at about 3 or 4 in 12. The outboard end of the shed should be about a foot above grade, no more is necessary or desirable (you have to step up over the short wall, remember). Instead of putting a fixed roof on it, you put double doors instead that open right and left from the center and give you access to the stairway. Put a good weatherstripping at the astringer This kind of stairwell protection was quite common in row houses built just after the war.
2. If the stairway will be used on a daily basis, you need to build a full-height shed with a gable roof (to shed water away from your point of entry) and a weather door. Plan on running an electric line into this shed to light up the stairwell and the entry door. If you can design your stairwell so you've got a good sized landing at the top, set up your weather door to swing inwards over the landing so you won't have trouble with snow blocking it in winter.
Dinosaur
'Y-a-tu de la justice dans ce maudit monde?
It's code here to tie the stair drain to the sump pump. I have a problem with everyone I see without a battery backup. I'm in hurricane country and the thought of 10" of rain in an outside drain with no electric just isn't a good thing.
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