Leaking basement: whose responsibility?
Folks – I’ve been lurking here for the past 6 months or so, and have learned a lot as I’ve gone through putting a small (14’x28′) addition onto my home. I appreciate the level of knowledge here, and would like to ask for help on a problem.
We are just about at the end of the project, which has a full foundation with a slab. The slab was poured about 6-7 weeks ago, and I continue to get water seeping in, mostly along the junction of the new foundation/new slab and existing foundation (down both vertical edges where new/old meet and along the horizontal line of the slab’s edge at the existing house). It was a pretty wet spring around here (northern CT), and for a variety of reasons it had been literally a muck pit down there prior to pouring the slab, so initially I wasn’t worried, just figured it needed time to dry out, and let the footing drain we’d put in around the addition do it’s thing.
Now, though, it’s been pretty dry and hot, the ground outside the addition is rock-hard dry, and I’m still getting the seepage, so I’m wondering what to do.
My first question – when the slab was poured, they poured it right onto the dirt/mud, no sand or gravel underneath. I had asked the GC about this, and he claimed it made for a stronger slab. It seemed odd to me then and still does, but I didn’t have a chance to look into it then. Could this be the source of the problem, or is this indeed an ok practice?
Second, is the GC responsible for solving the seepage problem? I hadn’t asked him about it yet, wanting to seek opinions here first. The contract doesn’t specifically cover this, just states that he is to “Dig full foundation w/pass through, waterproof, concrete floor”. (I assume the “waterproof” refers to the stuff applied to the outside of the new foundation walls).
Lastly, any ideas on solutions regardless of who does it? I’d been thinking of using something like “Damtite” or “Quickrete Water-Stop”, (I think they are refered to generically as hydraulic cement?). I’ve used those a time or two before, but I think they are supposed to be applied into a crack or crevice, and there really isn’t any crack or opening into which the stuff could be inserted here. I had planned on sealing the walls and slab with Dry-Loc or some similar product, but I’m not sure that sort of thing will hold up to actual water coming through – I think those are mostly to prevent vapor getting though.
Sorry for the length of this post, and I appreciate all thoughts and ideas.
Ken Platt
Replies
OK, I need to ask some questions. (Everyone will want to know)
Does the contractor have Liability insurance?
Was this job done with permits?
When the slab/foundation was poured, how was it tied in to the existing house? Did he use rebar installed into holes he cut into the existing concrete to pin the old & new parts together?
When he excavated or whatever, did he lay drains around the perimeter?
Once the slab/foundation was poured, how did he waterproof the concrete walls? I assume he did something, according to your post.
If your contract says waterproof, he should be responsible.
Personally, if it were my home, I would be talking to a lawyer.
I've never heard anyone around here suggesting a non-compacted pile of earth as a strong base for a slab. It WILL fail.
If things are exactly as you describe, the contractor has a rebuild in store. I would not pay one cent more.
But then, what do I know? I'm a Canuck.
Quality repairs for your home.
AaronR Construction
Vancouver, Canada
Liability insurance would have nothing to do with this situation--it's not a warranty. The permit or lack thereof is probably irrelevant also, because in most places I've built the inspectors do not come out to inspect subbase for slabs. If they look at the drainage system it will only be a glance.
"because in most places I've built the inspectors do not come out to inspect subbase for slabs."
Buddy of mine recently had to rip out and replace his vapour barrier prior to slab pour, 'cuz inspector didn't like it....must be us canucks
I don't know, Dave. If the contractor does a lousy job, and you sue after due consultation, liability insurance will help you get a financial settlement even if the contractor declares bankruptcy. I tell people in the first interview I carry 2 mil liability.
Your inspectors are probably different than the ones here. So much trouble over substandard building practices and leaking houses, the guys now check. It's different in every area, I know.
Still and all.....no compacting of the base, no gravel, pour on mud?
Water leaking in from the seam means poor drainage, bad waterproofing poor building practice. We are in the same geographic area with a lot of the same water issues.Quality repairs for your home.
AaronR ConstructionVancouver, Canada
Maybe Canada is different, but down here... I've read every boring word of my GL policy and it's all about property damage and bodily injury. So, if I did what the OP's contractor did (obviously a horrible job of installing a slab), my insurance company would not be defending me. Now, if I did that on an addition and the water infiltration damaged the EXISTING house, that's a different story.
Dave, I've built in both NJ and CT. Both of those states require under-slab inspections. They check the base, the vapor barrier, the radon piping, and for any required reinforcement. I'm surprised as can be that the poster's contractor was allowed to pour a basement slab on grade with no gravel as a capillary break.
AndyAndy Engel
Senior editor, Fine Woodworking magazine
An updated profile is a happy profile.
Other people can talk about how to expand the destiny of mankind. I just want to talk about how to fix a motorcycle. I think that what I have to say has more lasting value. --Robert M. Pirsig
Aaron - thanks for the reply. The job was done with permits, the guy does have liability insurance, for what ever that's worth.
I'm afraid I don't know how the new was tied to the old. I'm finding out to my chagrin that there are a number of these details that I didn't know to check as the job was done.
There was a footing drain around the outer perimeter of the addition, which seems to be working (I can see water draining from the pipe opening about 40 feet away). The water seems to be coming in from the other side of the addition, where old and new come together.
I'll be addressing this with the GC later today. Thanks again.
Ken
At the start of the planning process, did you take into consideration the water table in your specific area. You could have gone down to your board of health and they could have given you a "as built" of you septic system. This would indicate the water table at your location. If you are into the water table, you will have seasonal water seepage or even worse. You should check this out asap. Could be a good bargaining chip with your GC. Good Luck. Jim Z
Jim - I hadn't really worried too much about the water table since I have an existing basement adjacent to the new one and it's dry except for the odd massive rainfall. I have my woodshop down there, my wife has her sewing setup, I'm sitting down there now typing this. So I didn't really anticipate water problems, and I'm still baffled as to how I can be getting water coming up on one side of the wall (new area) and not the other (existing basement).
Ken
Ken, what I would do then is hire a civil engineer to evaluate the soil conditions and what actually is happening with your problem. That way, everything could be documented and you would have concrete proof that something is a not up to snuff. This might seem like over kill, but it would be a outsiders view into the water problem. By the way, my neighbor just had a waterproofing company do his basement at the tune of $9000. He is into the water table, he has had knee deep water several springs in a row. Good Luck. Jim Z
I see my Q about daylight drain has already been answered. But if he choked up the drain with bad fill instead of clean washed stone for foioll, he has prevented much of the water from getting to the drain so it is finding it's own ways tro run underground, some of them to the inside of the house.To tie a foundation wall together, here is what I like to do.First, the new foundation should be simm,ilar and at least as dep as the existing, poured on firm undisturbed soil. ( Mud is not undisturbed) This is so that the new work does not settle down later and offer a resulting crack to invite water inThen, I will cut a keyway into the old foundation wall. This further prevents shifting of the two sides and the added mileage and shape creates an added barrier to water ingress. Think of a tongue in groove flooring joint. That is how a keyway looks in cross section.Then I drill the old foundation wall and either drive in rebar or over drilll and epoxy the new into it. Sometimes, I have p[ainted the connection strip with bonding agent too in unique corcumstances. When pouring, the form oil should be kept off the keyway area though for any joint like this.after the crete is poured and the forms stripped, if ANY flaw shows in the joint, it is time to get out the hydraulic cement to seal the OUTSIDE of the seam. Then she gets the same waterproofing as the rest of the wall
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
You're reading things into the original post that aren't there. He didn't say that the under-slab soil was muddy or un-compacted, just that there was no sand or gravel.
Let's assume there was sand & gravel, and that the soil was compacted, and further that the soil dried out and shrunk back or depressed in some places. Do you expect the sand & gravel will move in and supprt the slab? No, of course not. One of the purposes for sand under a slab is to level the surface.
I'm sorry, I thought you wanted it done the right way.
If this project was built from a set of plans and with a building permit approval for the plans, there should be an elevation for the foundation that specifies base for the slab and footings, rebar, vapor barriers, etc. Inspectors here will look at that detail and verify that compacted base, vapor barriers, reinforcement, perimeter insulation, etc. is to the plans before giving the go-ahead to pour concrete.
I'm on the West Coast and I know there are some regional differences, but, in my experience, no competent builder in his right mind East or West would pour a residential slab on a muddy, uncompacted base. The results of that include uneven settling, cracks and fractures, leaks, etc.
I encountered one a couple of years ago on a pole barn floor (no inspection required since it was an agricultural accessory building); the owner had similar concerns as yours when he discovered no base had been put down, had some sections of the concrete floor sawn out. The soil had dried and settled and the bottom of the slab was bridged over the soil by over an inch....in places I could slide my arm beneath the slab as far as I could reach.
The owner had a plan set for the builder that specified 6" of compacted 3/4" minus gravel (you probably have a different name for it in Connecticut) which was never placed. He sued the contractor for replacement of the slab and won. The contractor was a known hack; no longer in business....
Myself and others removed the entire slab and replaced it.
Each jurisdiction has it's own ways of settling issues like this; here, there is an arbitration process with the Builders Board that is a beginning, at least.
But as a builder myself, I would hope a customer would confront me first and give me the opportunity to make corrections. But you need to do a little homework so you've got your ducks lined up before you pursue this issue, so if the guy tries to blow you off with some fairy tale, you're prepared to make an informed response AND an ultimatum, if need be.
Good luck.
Ken, where in CT are you? Northeast or northwest? The soil drains in the northeast, and not so much in the northwest. What did the contractor use for waterproofing? The CT code is quite specific on this issue, and regular old foundation tar doesn't cut it anymore. It must be waterproofing, such as a self adhering membrane, Delta-FL, or the spray-on stuff. Was there a backfill inspection?
Andy Engel
Senior editor, Fine Woodworking magazine
An updated profile is a happy profile.
Other people can talk about how to expand the destiny of mankind. I just want to talk about how to fix a motorcycle. I think that what I have to say has more lasting value. --Robert M. Pirsig
Andy, greetings. I'm in Granby, near the Mass border. After reading the replies, I called the local inspector who told me that a vapor barrier of 6 mil poly is required under the slab, but gravel or sand is not required, although it is better.
The same inspector was out here a couple of times during the job, but did not inspect prior to the slab being poured. When I talked with him a few minutes ago, he told me that he'd recommended to the GC that they use "clean fill" to do the lower part of the backfill outside the foundation to improve drainage to the footing drain. I'd not heard that previously, and it was not done. I don't know if a specific backfill inspection was done, and I'm not certain what was applied to the outside of the foundation to waterproof it. There was black tarry material placed on it, but I didn't know to check on it beyond seeing that it was there.
You know, I thought I was being pretty careful with dealing with this GC, but I guess I didn't do as well as I'd thought....
Ken
OK, I'll jump in here now.your contractor is definitely a hack, and the story he laid on you about pouring on muddy dirt making it stronger was a lie, straight out. And since he failed to use clean fill around the perimeter drain to facilitate water movement away from the foundation after the inspectoir told him to, he is worse than a hack. it ias sopunding like he did efverything he possibly could to gaurantee that your foundation would leak.I started out thinking in this thread, "maybe it is just a problem with high water table and it is hard to seal a joint between old and new, but it seems like a good perimeter drain would be leading the water away before it could leak in..."but he has suffocated whatever drainage he might have installed. BTW, did the drain lead to daylight or is it just plain dea end buried with no place for water to run off anyway?The slab on mud? If you ever do get teh drainage working right, the mud will dry and shrink, settling out and leaving the slab floating in midair, so it is certain to crack. Then, with no VB under it, water will be driven up as will any radon.This guy need concrete overshoes and a hard shove off the end of the pier
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
you mentioned in one of your posts that there is a footer drain to daylight on the outside which seems to be functioning.
is there a similar drain on the inside of the footer ?
if the answer is no-
i would be willing to bet that if such a drain had been installed on the inside and run to daylight with a crushed stone slab base you would not be having this problem.
these two things are standard construction practices that should never be skipped.
And, most importantly, they are so inexpensive on the front end and extremely expensive on the back end that they should always be done
on the front end
carpenter in transition
Tim - No, there's no drain on the inside of the foundation. One of the things the inspector mentioned to me today when we talked is that apparently he'd suggested to the GC that some sort of drain be placed under the slab to drain to the outside-foundation drain. He used a term I've already forgotten, but I got the idea he meant some sort of perforated pipe bedded in crushed stone under the slab running out to the footing drain outside the foundation.
I guess it'd have been nice if the inspector had mentioned his concerns to me, but I gather he has to walk a fine line. He's been very informative when I've asked him questions....but here unfortunately I didn't even know what questions to ask.
Thanks for the reply.
Ken
the solution to your problem is simple, the execution hard
-jackhammer the basement slab
-excavate at least six inches of soil
-install four inch perforated drainage pipe around perimeter of foundation
-additional piping can cross beneath the slab in a few places
now for the hard part
-connect new drainage pipe to exterior footer drain or run this new pipe to daylight.
the fact that the grade at your residence allows a pipe buried at footer depth to make it with slope to daylight is a tremendous blessing and one that shouldn't be wasted. most homes don't have this capability and are stuck with sump pump tanks buried in their basement floor. this requires the use of a sump pump and an outlet pipe that usually dumps above grade outside the home. sump pumps can fail for various reasons and none of us like an outlet pipe dumping water on the ground outside of our home at random times. when you have the ability to use gravity you should go with it.
-install clean, crushed stone slab base to allow at least 4" slab thickness
-install 6 mil reinforced polyethylene vapor barrier
-pour concrete floor slab at least 4" thickness
see how much easier this could have been ?
your builder may croak when you demand he do this, but he screwed up and you are going to suffer forever with a wet basement if you don't push. he may try to talk you into a sump pump tank and a sump pump but you really don't want this. it sounds like your basement runs wet year round and the pump will be running all the time at your expense.
this is the only real solution for this problem. people will suggest fillers, pastes, epoxies, coatings, caulks, and sealers, but they are all just a short term fix.
carpenter in transition
Hi Ken,
I recently had a similar problem on new construction with the rear of the house basically framed inside a 26' retaining wall. Everything was done to code including compaction, poly vapor barrier under the concrete, perimeter drains (properly located at base of footing running to a below slab sump etc. The concrete wall was waterproofed outside and dampproofed inside and yet the next spring I had water forcing its way in between the slab and footing at the base of the retaining wall. I sealed this joint using a product called "Deep Pentrating Sealant" made by Evercrete "http://www.evercrete.com" which resolved the liquid water problem. Unfortunately I still have a dampness problem which radiates out from the wall/slab junction after a long wet spell. I have researched this extensively and I believe my problem is being caused by capillary action which is drawing moisture up from between the poly vapour barrier which is sitting on the top of the footing and under the slab. I am trying to figure out what to do but in the meantime will continue with a couple heavy coats of Evercrete at the junction and see if that works. Some good info on the cause is at:
http://www.buildingscience.com/resources/resources.htm
If you find out a solution I would sure like to know. Good-luck!
Lazera, thanks for the pointer to the Evercrete. If I can't get the GC to do something about this I'll spring for a gallon. It looks like a better product than the UGL Dry-Loc which I have on hand.
Ken
Sorry but you have been fucxed!!