Hello,
I am a small builder in NC. I have a house that I built on a crawl space that is getting some water in the crawl. I have tested the water and confirmed that there is no chlorine so it appears to be ground water, not city water. The water seeps in quite slowly, generally taking about 2 weeks to hit the max fill point of about 8″ in the low spot of the crawl space. It seems like my best bet is to install a sump pump.
I have never done a sump pump. All of the info I have read seems to point to using corregated pipe wraped with landscape fabric to catch the water and divert it to the pump. My question is, is this the best way to go? It seems to me that a 4″ hard PVC pipe drilled with holes and wraped with landscape fabric would be better. If I use the PVC, I could install cleanout points where you could run a snake in to clear any mud that might settle over the years. It is hard to picture a snake going through a corregated pipe very easily. It might take years to notice any difference, but it seems like a better solution.
Is the PVC a good idea? Also, would I be better with 2 2″ pipes side by side rather than one 4″?
Thanks for any advice.
Doug M.
Replies
You can try just putting the sump in a pit in the wettest area. Depending on the soil you might not have to put in drains to the pit. Its worth a try to see what happens, unless you are really anxious to start digging in the crawl space.
Thanks for the advice. I would like to install the collection lines to get the water out of sight. This portion of the crawl space has about 7' of head room. I specifically designed the floor system above to keep this area open for storage. Of course, now it has 8" of water.
What I am curious about is how to build the collection pipes. My plan is to dig down to the footings and put a hard PCV drilled and wraped with landscape fabric, back fill with river rock and then final cover.
My question is about the hard PVC vs. corregated pipe. Also, once I put the collection line in, should I cover the area with poly and then crushed stone?
Thanks for any advice.
They make SDS pipe with the holes in it, you don't have to drill anything. This is a smooth pvc pipe. Most times the installation is filter cloth, 4 inch of stone, pipe, 4 more inches of stone, and wrap the filter cloth over the top, you can put c.o.'s where you need them. Try to maintain fall to the sump. Most codes do not allow 2 inch on a perimeter drain. Lots of luck.
"If all else fails, read the directions".
Is the foundation still open (not back filled)? Unless the water is perc'ing up throgh the ground (not very likely) you'd be better off installing the drain outside the walls per Shacko's approach. Bring a pipe in to a sump, install a pump, and you're done. Use that rippled water-permiable board against the foundation to keep water away from the foundation and the basement will not be humid.
Brooks
Thanks for the advice. The house has been occupied for about 4 months. The water seems to be coming from both outside and inside. In the crawl space I dug a hole about 1 + foot deep a good 5' from the exterior wall and it filled with water in about 2-3 days.
I have about 2' of unbalanced fill on the outside of this foundation wall. In the crawl space, I dug down to the footings in two spots, about 18" or so and you can watch the water slowly trickle in where the foundation meets the footing. It is very slow, but if you are patient, you can see it trickle in. Add that to my 1' hole and I have concluded that I should try to put the drain both inside and outside. A rippled water board is a great idea and one that I had not thought of. Just to make sure I am clear is this correct from the bottom up:
- footing, filter cloth, 4" of stone, pipe, 4" stone, filter cloth
Is this a single sheet of filter cloth so that I am essentially wrapping the pipe with 4" of stone all the way around and the cloth to hold it in place and keep out mud?
Thanks again for the advice. Not looking forward to the digging. The outside wall is under a deck with about 4' of clearance. I need to go about 3 1/2 feet deep on the outside for a run of maybe 15'. Fun, fun, fun.
Doug M.
Doug: The water is "probably" traveling laterally. I'd try the outside stuff first, then add the inside stuff if needed. If neither works you need to tell the HO that he's living on top of an underground spring. To give you a small smile, one of our neighbors lives on top of a filled-in creek bed - his sump pump runs nearly continuously...Outside: Dig to footing. 4" gravel (I like 3/4"). Then flex footing-drain pipe, the kind that comes pre-wrapped with filter cloth. If there's below-grade windows, "T" the flex & bring it up to daylight in the wells, capping them for clean-out access. If grade will allow, take the drain to daylight, otherwise to a sump & pump. Add perimeter ripple-board to grade, at least 6" more of gravel, then back-fill. I love the ripple-board, as if you seal the walls you can have a really dry basement. Drop a dehumidifier water-outlet into the sump and you'll want to sleep there in the summer!Inside: The same, without the ripple-board.Make sure you provide clean-outs!Good luck! And tell us how it goes?Brooks