How do I keep water from coming under my basement door?

June 14, 2007 5:10 PM

Looking for ideas on how to stop my basement door from leaking.

The door is at the bottom of 5 or 6 steps, directly under the bay window from the main floor of the house. There is a drain in the center of the landing outside the door. The problem I have is that when we get heavy rain, the drain has trouble keeping up. Add in a leaf or some mud to partially block the drain and its even worse. The door threshold is very low - barely a quarter of inch, so it doesn't take much for water to come over the threshold and under the door.

I thought about putting in an awning to keep the area dry during rain, but due to the bay window I don't think that is going to work. At least attaching anything to the house will be very problematic. I believe the primary problem is the water coming down the stairs during rainstorms. I've given some thought to buying a box of industrial absorbent socks like are used in factories and simply leaving a couple on the steps to catch the water before it gets to the landing. Not sure if that will work...

DIY / cheap ideas are best, especially since I'm spending over $1000 tonight on carpet drying, anti bacterial / mold treatments, etc. However spending some cash with a contractor to avoid another episode like last night is certainly ok.

Has anybody had to deal with this?

posted by COD to home & garden (6 comments total)

So, I'm envisioning concrete steps down to a door, no hatchway or anything, a drain at the bottom of the steps with insufficient capacity, and then you have a carpeted room on the other side of the door?

If that's correct, you absolutely need to keep water from going down those steps. Industrial socks won't do much in a heavy rain. It's hard to envision why the window prevents some kind of awning or hatchway, maybe you could post a picture?

I assume at least there is not water draining into the stairway from the ground outside it, or off the roof above. Those would be the first places to address, with proper ground sloping and gutters. And I assume you have had the drain roto-rooted.
posted by beagle at 6:24 PM on June 14, 2007

What beagle said. First, make sure that drain is working as designed. Where does it drain to, is it clear, and so forth.

Second is preventing rain from getting into the stairwell. Has something sunk or changed in the landscaping that is channeling more water into the area? Create a couple of swales if you need to.

Then address what's coming off the house, which could also have changed drainage patterns (e.g. new wing or dormer). You may want an awning or a half-roof over the door.

Last, since the basement is now finished and furnished, you may want to consider raising the threshold as a just-in-case. Depending on the door you might be able to just cut it back and install a higher threshold. Get a modern one that will seal against the door with spring pressure.

You could also consider, if you think sometimes you just get too much rain in too short a time, that a dry well under the stairwell would help the drain out.
posted by dhartung at 6:33 PM on June 14, 2007

Picture of the stairwell.

I cleaned the hell out of that area late today - I think the dirt down there must be from the water contractors pumping out to that drain this evening. It wasn't there at 4 PM, honest! I do have a sump pump and it works fine. I believe that drain in the stairwell runs into the sump pump. I cleaned it out today and put a hose in it on full blast and was unable to get it to back up. However, if I point the hose in the stairwell and let it go it has trouble keeping up. So the drain itself is clear. What I have I think is a design issue in that the opening of the drain does can not process water quickly enough in a heavy downpour, and the confined area pretty much ensures that any leaf or dirt that gets down there will end up hampering the drain as well.
posted by COD at 7:45 PM on June 14, 2007

From looking at your pic...

Your setup is very similar to ours. We had a DELUGE that flooded our basement, with more than a foot of water outside that door - seeping in constantly. Water was literally cascading down the stairs into the stairwell. To make matters worse, the drain at the bottom of the stairwell drains into our sump pump, which couldn't keep up. Water was welling up out of the sump pump and flooding across the partially finished basement floor. I've done some hellish nights in the Navy, but that night was one of the longest of my life.

Our solution? Temporary... installed a much bigger sump pump (60 gpm), installed new weather molding on the door to create a tighter seal, and bought sandbags to place against the door whenever a situation like that happens again. The weather sealing on the door has helped out the most during minor storms as water no longer 'seeps' in. Unfortunately, our ultimately solution is re-grading the area that allows water to flow towards the house so that it flows AWAY - which will be expensive but in the long run will save us the $5000 it cost us to replace the tenant's floor.

Good luck.
posted by matty at 8:50 PM on June 14, 2007

The grading at the top of my stairs is actually fine. It slopes away from the stairwell in all directions. I think the concrete pas at the top may have settled in the wrong direction though. I need to get out this weekend and check that.

Replacing the weather seal is a good idea. Maybe Home Depot has something specifically designed for doors that tend to get wet. I'm sure the builder used whatever was cheapest.
posted by COD at 4:50 AM on June 15, 2007

Besides everything already suggested -- from the pic it looks like there is headroom under that bay window, so you could cover that part with a sloping roof over the landing. Then if you could put an awning-type roof higher up, next to the bay window, over the stairs, you'd be all set. If might not look fabulous, but it's the only sure-fire solution. Without a roof to keep water out, since the drain relies on the sump pump, if a good thunderstorm knocks out the electricity, you'll be under water again.
posted by beagle at 9:28 AM on June 15, 2007