Harry asks,
My question is about basement waterproofers. I have a problem with my basement flooding, and a waterproofing company charged me $14,219 to correct it. Two of that firm’s inspectors insisted that underground water was being forced up into the cellar via hydrostatic pressure and only a French drain would correct it. So the basement waterproofers installed a long, deep ditch running alongside the interior of the home’s foundation walls. In turn, that graded ditch was supposed to gravity-feed rising water into two underground electric pumps (at opposite ends of the basement) and eventually pump incoming water into the city sewer system.
On the other hand, I felt the water was coming from the surrounding earth through a rather thin foundation wall, and slowly running down into the cellar doorway. Now it seems that I was correct. The basement waterproofing company is stalling, wanting to take photos and “brainstorm” their next move. Do you have any suggestions about how to deal with these basement waterproofers?
Tom Kraeutler
Its possible that the chimney structure itself is leaking. Things to check there are the chimney crown for cracks (at top of chimney, mortar between clay flue liner and edge of brick). You can also apply a masonry sealer to the outside of the chimney to reduce absorption.
I’m glad you have those extensions but just in case, make sure the gutters are not overflowing. Go outside in the next heavy rain and watch whats happening to the water. It could also be that there is too much roof surface headed to one spout. Each spout should not handle more than 400-600 sq feet of roof surface.
As for the sump pump, people generally put too much emphasis on this. Its going to fill if you have a sub-slab drainage system that discharges to it (which you dont need). Otherwise, its made to give big floods a place to drain. Its not going to collect small leakage from a chimney wall.
Ron AA
Thanks Tom. We have downspouts 6 feet+ away from foundation. There is some gap and poor grading around chimney facut stone below the deck and we also notice water is seeping out exactly below chimney basement.
I agree there is no need for interior french drain as it’s outside grading/rain water problem. One of the contractor is giving suggestion to pour concrete around chimney stone below deck and then grading. Is this a good solution.
Why water is seeping out on the basement floor instead of going into sump pump well. Is there way to check/fix existing interior drain system?
Why are there Styrofoam fill on the existing drain?
thanks
Tom Kraeutler
Ron, by your description I can tell that there is absolutely no reason for an interior drain here. The cause is poor exterior draining and you just need to figure out where this is happening.
The first step is to trace every single gutter and downspout and make sure they are (1) clean and (2) extending the run-off at least 4 to 6 feet, or more, from the foundation. You mentioned that you had an issue under the deck. Are there any downspouts discharging in that area? If so, you must extend them.
I have seen this kind of thing before – and actually very recently at a friends house. A water-proofer had quoted him $13,000 to install drains and all he needed were leaders added to his downspouts! Under the deck he used 4″ PVC pipe connected to the spout and ran it out to grade at the end of the deck closest to the back yard. Problem solved! Read this post for a more complete understanding of why the basement is leaking and how to fix it.
Ron AA
This is 18 year old house and we are living in this home from last 5 years and we saw 2 times water ( around 2 gallon of water) at corner of foundation wall and unfinished basement floor. This happens only very heavy rain is hitting the wall at angle. Last week we noticed water was seeping out slowly from crack between foundation wall and floor when heavy rain was hitting the same wall and sump pump well was dry. This part of the wall is below the deck and there is gas fireplace chimney with stone masonry on top. There are lot of gravel and stone without grading below the deck but no dirt/top soil which may help in better grading. There are few cracks in the basement floor too. There is some kind of existing drain flashing run along with the foundation wall which is covered by some type of green Styrofoam. Every waterproof company is giving same interior french drainage installation along with the only one side of wall and no one is telling me why this water is not going into sump pump well.
I would appreciate your suggestions and It’s not emergency so we can try some solution before spending $1500-$2000. Thanks.