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leaky foundation

It seems as this is a common discussion. I have 120 year old victorian with 20" thick field stone foundation. There is one area where ground water is coming in when we have saturating rain. My gutters and downspouts do well and are not near this problem area, ground is graded fairly agressive in the area against foundation, I would rather stop the water outside rather than in, and am open to different ideas and not afraid of excavating if it will do the job. The ovrall site is fairly flat ground so if french drain is idea, where does it drain to? Is there a spray on rubber membrane to seal the stone below grade, outside? I have looked at sheet material, but with uneven stone surface that is not practical. Thanks

Re: leaky foundation

You might consider having an exterior footing drain/French drain and/or an interior drain tile system and have them both drain to an interior sump basket. Then you could have a sump pump it out. The exterior drain system would stop the surface water from entering the basement. The interior drain tile system would handle ground water coming up from below.

Re: leaky foundation


I hate to be the bearer of bad news, but yes, this sounds like it's going to require exterior excavation down to the base of the foundation, and the installation of a french drain.

I DO NOT agree with the previous poster that the french drain should empty into a sump pump inside the foundation; this is just extra work & allows a path for water to enter the cellar.

The logical approach is to keep as much water out of the basement as possible.

The Popular Mechanics site below has a diagram of how the drain tile (which is a 4" perforated plastic pipe) is placed.

The worst part of the job is, of course, digging the trench down to the base of the foundation; this is heavy work; if the design of the yard allows, a backhoe is brought in to ease the work required.

It's unknown how easy or how hard the digging might be next to your foundation; each piece of property has its own characteristics.

You may find easy digging all the way down, or you may hit very hard soil (hardpan) at say, 2 feet down; you'll then have to resort to pick & shovel work to remove the rest, which can be tough.

If the trench is unstable, it has to be shored up with plywood forms & bracing to prevent a cave-in.

Once exposed, the foundation is pressure cleaned with a water hose & allowed to dry.
The trench is extended away from the foundation to an outfall (lower point, if there is one in the yard so the water has a place to go), or to a dug drywell, which is at a lower point than the drainpipe placed at the foundation.

A drywell allows water collected along the base of the foundation to collect in the drywell & eventually soak harmlessly into the ground, 15' away from the foundation.

The foundation wall is smeared with roofing cement (this is the consistency of soft margarine) with a stiff brush & then covered with 4 mil plastic sheeting.

The bottom of the trench is covered with 12" of crushed stone; landscape fabric is placed over this to keep the fine dirt particles out of the drain.

The trench is then backfilled.

The sump in the PM diagram is installed ONLY if there continues to be a water leak problem into the basement.

This is heavy work, but the materials cost is very low; perforated drain pipe, roofing cement, etc. are low-cost items, so it can be done as a diy project

But the diy'r must not overdo it; work only 3 hours a day at excavating; that's plenty for one day; then quit.

The job will get done before you know it.


Re: leaky foundation

Ideally you’d have the French drain run to daylight. But metalformer’s yard is flat so that apparently isn’t an option. I’m not so sure a drywell is the best solution for a foundation drain. It would have to be so far underground to be lower than the foundation drain. What if there was a problem with it? It would be very hard to access.

Either way, be aware that digging that deep is really not a DIY project unless you properly stabilize the soil in the trench and you really know what you are doing. People have been killed by trenches caving in on them. It can happen easier than you think. The guy I sit next to a work bought his house from the widow of a man killed by a trench cave in in his yard.

Re: leaky foundation

A sump pit is the way it is done around here. (mi)
You wont pass your underground plumbing inspection without it. The perforated pipe is placed around the exterior with bleeders that run under the footings that are connected with solid pipe to the sump crock.

There was a product that some builders used called "rubberwall" That was sprayed on and is a green color. I haven't seen it in several years so I don't know if it still exists. You could do the old tar standby or try the ugl drylok as a coating. I would do that in combo with the drain.

Re: leaky foundation

I prefer to let the original poster decide if "it's not really a diy project"; the poster in fact expressed a preference to "stop the water outside, rather than in", and was not "afraid of doing excavation, if necessary".

Nor was there anything in my post to prohibit the poster from getting helpers to do the project, or for hiring a contractor.

It's an awfully cheap shot to insinuate that someone "might be killed" after I explained the caveats and precautions needed to be taken on this project.

using THAT logic we may as well close down the forum; anyone "could be killed" on a roof nailing shingles, or changing a light bulb or an electric receptacle.

The idea of connecting a perimeter drain to an interior sump is absolutely ludicrous.

This is a sop allowed in the code by many local jurisdictions to the homebuilders & real estate agents who don't want to spend the money to do the job right in the first place, so they cut corners by putting in a sump pump.

You'd have to be a little loopy to buy a house in the first place if you see a sump pump in the cellar.

Of course, an inside basement sump relieves these sharpies from any damage culpability if the pump fails, or is over whelmed (which happens often).

It's the homeowner who suffers & pays the damage when the basement is flooded & the property insurance premiums go up.

Though not specifically prohibited by the International Residental Code (it might hurt business), it has always been deeply frowned upon to connect the outside perimeter drain to any inside drains, or to an interior sump pump well.

There are innumerable horror stories of basements flooding when there is loss of power to the sump (which happens often during a storm), or a soaking rain overwhelms the pump.

A single 4" drain pipe can flush 300 gpm right into the cellar in a bad storm; often 2 or more 4" drains are connected in tandem; there's no way in the world a cellar sump is going to keep up, even if the power doesn't fail, or the pump performs flawlessly.

The logical procedure is to keep the high-pressure storm water building up on the exterior foundation walls OUTSIDE the cellar & gravity feed it to a dry well or cistern, or outfall, whichever is avaiable.

This also has the tendancy to save a lot on electric bills & increase the chances of selling the house when the time comes.

if none of these options is available (highly unlikely), then an exterior electrically insulated sump is used on the EXTERIOR of the building.

Don't take MY word for it--I've only been doing this work for the past 35 years & have done a lot of digging & trenching in all those years, installing 15 such perimeter drains and dry wells;I wonder how many SherryH has done lately.

In addition, I have been contributing to these boards for many years.

Warren Goodrich is chief Building, Plumbing and Electrical Inspector for the city of Indianapolis; his site below at Self Help and More covers this whole topic very well.

Section 2000 IRC Part R405.1

http://www.selfhelpforums.com/archive/index.php/t-7504.html http://rd.com/familyhandyman/content/18297/

Re: leaky foundation

This is just wrong on so many counts it is ridiculous.
There are thousands of houses with indoor sumps. Everyone that has one is "a little loopy"? :eek:
I have yet to see a rain in my 33 years of life that "overwhelms" a sump pump. What really happens is it runs more often. Big deal. It is a device designed to pump water. Areas that have higher water tables install 2 pumps.
There are such things as a battery back up system or municipal water backup to compensate for a power failure.

Just because you do it that way in Indy, It does NOT mean it is correct anywhere else. I don't care how many "years" you have done it. You average out to less than 2 a year. The builder we work for does 15 per year. I have yet to even work on a house with a basement that doesn't have a sump. Even one that never ran as it didn't fill up with water, yet a block away they needed two pumps/crocks.
With modern basements being 8' plus into the ground, I'd hate to do all that digging and then have to dig even deeper to get positive flow to a drywell or cistern. Then what happens when they overflow? The drain tiles back up, water seeps into your basement at the joint where the wall meets the floor and you have a major problem.

For argument purposes, this may not be applicable to your situation, metalformer, but the other advice may not be either though he wont admit it.
The steeper your slope away from your house, the longer your downspouts, and the type of soil clay or sand all play into this as does your water table.

Re: leaky foundation

JacktheShack ... as someone who respects your knowledge and valued contributions in your posts I would like to add a little.

Here in this region it's mandatory for all new homes and additions to have the exterior perimeter drain into a sump pit being evacuated by a sump pump to the outside beyond the foundation no less than 8 feet. This is a dedicated system which can not be tied in to the sewer system exiting from the house. This has been in place since 1979 and has worked well for the most part and we have to live with it ... like it or not.

Re: leaky foundation

I used to respect his knowledge as well, but this post is so full of his opinions, I almost don't believe he wrote it.

Re: leaky foundation

To Jack the Shack,

I see that Graphite and canuk have already responded to your reply to my post. They made the main points eloquently so I do not need to further justify my earlier post.

This forum is a place for people to exchange ideas and advise. Sometimes there is more than one right way to do things. And as DwarfWytch pointed out there is a lot we do not know about the original poster’s house and yard. You offered your opinion, I offered mine. It is up to the original poster to consider the advice given and explore his (or her) options further. And as Graphite pointed out, things are often done differently in different parts of the country.

As to your years of experience…
This board is filled up with DIYers. I respect the years of experience that you have but that does not mean that DIYers don’t know anything. If you perpetuate the idea that only people with years of experience in any particular field have the right or ability to post on a subject, THAT will shut down the boards.

And if you look back at my original post I said, “Be aware that digging that deep is really not a DIY project unless you properly stabilize the soil in the trench and you really know what you are doing”. I stand by that 100%. If he (or she) knows what to do and properly stabilizes the soil and know what he or she is doing then it could be a DIY project. But as an avid DIYer I know that there are things I do not know. This particular homeowner might not be aware of how treacherous an excavated trench can be. This is a very important safety consideration that a DIYer might not have thought about. Your advice to shore up the trench with plywood forms & bracing to prevent a cave-in is good but doesn’t quite go far enough. A cave-in could be a nuisance. It’s a whole lot more than a nuisance if you are in the trench when it caves in and are killed or injured. This is a very important point that the homeowner must be fully aware of. Your contention that my bringing up this important safety point is “an awfully cheap shot” is beyond reason.

It is perfectly reasonable to disagree with someone. You can and should do so in a respectful manner. Your reply to my post was both inflammatory and very rude.

Re: leaky foundation

I recall a previous restoration project home where there was a stone foundation with moisture issues.
The professional foundation contractor had rectified the situation that seemingly been almost impossible to resolve. I had the opportunity to talk to him about this.

The first issue was the soil in this case is a gumbo clay that retains moisture like crazy. This gumbo clay when it becomes saturated and with the force the soil exerts on the foundation creates what is known as hydrostatic pressure.

The second issue is poor drainage which compounds the situation by allowing the soil around the foundation to become saturated and with the pressure of the soil forces to water to go somewhere … path of least resistance… the foundation. After many years of the stone foundation being subjected to this the mortar breaks down and will create a path for water to infiltrate.

The method he used was to carefully excavate the entire perimeter of the foundation to the footings. He repaired the joints of the stones then used a spray on specific industrial water proof membrane ( not damp proof coating ). A dimpled sheet product called Platon Foundation Protector, which is an excellent product, then covered this. Here is a link to their site : http://www.systemplaton.com/.
This did have it’s challenges because of the unevenness of the stone foundation compared to the relative flat surface of a concrete block or poured foundation.

They laid an exterior perimeter weeping system encased with fabric. In this case because of local building code restrictions these weepers were tied into an interior sump pit with a large capacity sump pump to evacuate the water accumulated. The trench was lined with a commercial grade ground cloth then stone was used to fill the trench to approximately two feet below finished grade with the ground cloth laid over top. Then topsoil was used to bring it up to grade for allowing bedding plants to be used. The purpose of the ground cloth is to prevent soil from migrating in plugging the voids of the stone and preventing water to percolate through to the weepers.

I asked why he didn’t approach doing it from the inside like other contractors proposed.
He explained the idea is address the source of the moisture and to prevent it from coming from the outside to the inside. He went on to explain that he would never do an interior method of drainage , unless something prevented addressing the issue from the outside. His logic is it doesn’t make sense to allow to moisture to penetrate from outside to the inside. For example allowing the water to flow from the outside under the footing to the inside and then drain it away could cause undermining of the footing … it doesn’t make sense.

Another perspective … food for thought.


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