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Lot grading, water percolation & french drain on the property line along the fence..How2 drain t
5

Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
I am now trying to understand if the current water drainage on my lot is wrong. The previous owner excavated the soil around the house and he probably spread the soil around the house in the backyard

Also my neighbor's property is on a higher grounds and I suspect his drainage is not 100% fair.

Below you have a representation of the rear side of the house, the left side house is mine.!



**The purple line** is the general slope of the terrain, as mentioned my neighbor's house is on grounds slightly higher than mine.

**The blue and brown lines** show the backyard general grading. The 8' strip that you see along my patio is not sloped correctly and I intend to fix that.

**The patio** drains toward the red spot where I intend to install a catch basin and I plan to drain that to a dry well south east of that corner

**Problems**

-the yellow line on my neighbors garage is a gutter that he extended on the soil and that currently drains on his property on the paved walkway that you see there

-by design both properties seem to drain the water toward the property line and that should at least affect the fence. As a matter of fact one of the poles is completely cut (rotten) at he base

-I believe that under the soil (subgrade) the water moves toward my house anyway due to the general slope of the terrain

**Questions:**

1. Looking at the measurements of the space between the garages **do you think that the water that the water that comes out his gutter (yellow on the figure) will infiltrate the soil and move laterally toward my property and my garage?** Just next to the garage the former owner built a small parking lot, paved with precast concrete blocks and I suspect that the base of that parking spot will suck all the water that makes it to it. Am I too worried about this?

2. Looking over the fence at my neighbor's patio one can easily see that when he built that he accentuated the slope and that now all that water drains toward the fence. I think that the only remedy here is to build a french drain along the fence which I should drain in the dry well that is in the plans for the patio. Is this a correct plan? **Will this french drain affect the fence in any way?**

3. **Is the distance between the fence and my house long enough to keep my house safe from that water which probably collects underground on the property line?** (not sure where it goes from there)

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

A few points missed. Is there a basement and is there a water problem, there? If there is surface water on your lot during rain, what is your concern about that? In other words what is your main concern that you want fixed?

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
This is my main concern

http://www.eng-tips.com/viewthread.cfm?qid=389727

I dp not think that this is a water table problem
That corner showed in the other thread is wet (efflorescence and capilarity) ONLU one one side of the corner
If it is a water table problem in should be on both sides

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

OG here again. Yup I thought this post was somewhat familiar.

As for me now, I've added enough. Maybe others will jump in.

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

I have looked at both of your threads, and honestly, this is almost a full-scale design job that you are trying to do via the forums. I think you are out of the advice column and into the "you need to hire someone" column.

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
Don't get scared by my diagrams
I am an engineer too and I know my limits
I need an educated opinion not a design
I just asked three simple questions, what is to design here?


As far as I am concerned my neighbor might need to hire an designer if I come to the conclusion that his water gets on my property. There is nothing that I can do on my property to prevent the water from his property to head to mine (if that happens).
In the mean time I learned (without hiring a designer) that a french drain should be used mostly in saturated soils where the water tends to accumulate or pool

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

You need to have this property surveyed before you do anything else. The distance between garages is of little concern, the slope of the land is. Is there a channel or swale down the property line? Even so, a 20x10 garage just isn't producing a whole lot of runoff. Why do you want to build a French drain? Does the lot not drain once the water hits the property line? Let the grade of the lot do the work. But again, you need a topographic survey of this area if you really want some decent advice or design help.

I wouldn't be too concerned with his runoff moving laterally to your house, unless there is some perched layers here? Impossible to know without further investigation.

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
That downspout collects the water for half of the house roof, not for the garage only. The house roof has a short downspout to the garage's gutter.
There is no swale. Probably there was one but the people just covered that with the fence and more soil
I am not sure that I understand what a topographic survey will bring me, what do they provide you when you ask for one?

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

A survey is going to show you the definitive drainage patterns on the lots. You can't really do any type of drainage analysis without one.

Try to see if you can get LIDAR contours at least for the site. If this gets contentious with the neighbor, he may not let you survey his property anyway.

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

Quote (mini)

**do you think that the water that the water that comes out his gutter (yellow on the figure) will infiltrate the soil and move laterally toward my property and my garage?**

groundwater will spread in all directions, irrespective of the slope of the surface. it will follow the path of least resistance and will go downward unless it hits a clay or rock layer. it will not turn and go towards your garage

Quote (mini)

Looking over the fence at my neighbor's patio one can easily see that when he built that he accentuated the slope and that now all that water drains toward the fence. I think that the only remedy here is to build a french drain along the fence which I should drain in the dry well that is in the plans for the patio. Is this a correct plan? **Will this french drain affect the fence in any way?**

there are other options (berms, pipes, swales) and a french drain would not by my first one

Quote (mini)

**Is the distance between the fence and my house long enough to keep my house safe from that water which probably collects underground on the property line?**

see the first point, water does not "collect" underground

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)

Quote (cvg)

groundwater will spread in all directions, irrespective of the slope of the surface. it will follow the path of least resistance and will go downward unless it hits a clay or rock layer. it will not turn and go towards your garage

The above is the key for my problem
I have two paved surfaces with limestone screening only as base (no gravel)
These limestone layers (under the paved area where you see the boat and under the patio) are both near an area where the water from my neighbor could go (lowest point on his property is the fence line, which is also my highest) The paved area under the boat in next to the area where he drops his rain water from the garage, right in the middle of the paved walkway next to his garage

I have no idea if that water could make its way into the limestone screening layer under the pavement that is under my boat.

With less chances the same could happen with the layer that is under the patio

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

3
OG once more.

I look at the discussion here and your other post and I give a similar example for your consideration.

There once was a very experienced carpenter who built all sorts of buildings and they all performed
well, met codes because he researched the materials and educated himself on rudimentary design, almost to the point
you could say he might qualify for a PE license. However, he had one recent problem and decided he would post
a question on Eng. Tips.com in the electrical engineering forums. He had been drilling a lot of holes for
anchoring structures into concrete slabs. Darn if he kept burning out his electric drills powered by a
portable generator about 300 feet away from the work. Early versions of the drills were made in
China so he figured he had better look to those made in the USA. Even then, with some of the most
expensive drill, the darn cheap things, kept burning up. He wanted to know what brand would not burn up.
The comments he got on his post dealt more with
the kind of extension cord he was using, but he then brought up other factors, maybe generator was too
low a rating, even though its meter said 110 v when under load. A return to the forum and questioned how he
could evaluate that generator. Some one then asked the wire size of his extension cords.

He replied the wires were certainly long enough and even an extra 50 feet was available for moving around the site.
So it goes on and on with him not wishing to replace his extension cords, since they were a gift from his father
and his dad never had any trouble with them.

When asked if he had any electrician friends that might help him, he couldn't see any reason, since he did all his
own wiring and they passed inspection. He knew enuff about that subject. Now all he wanted to know was the best electric drill to buy.

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)

Quote (oldestguy)

OG once more.

I look at the discussion here and your other post and I give a similar example for your consideration.

There once was a very experienced carpenter who built all sorts of buildings and they all performed
well, met codes because he researched the materials and educated himself on rudimentary design, almost to the point
you could say he might qualify for a PE license. However, he had one recent problem and decided he would post
a question on Eng. Tips.com in the electrical engineering forums. He had been drilling a lot of holes for
anchoring structures into concrete slabs. Darn if he kept burning out his electric drills powered by a
portable generator about 300 feet away from the work. Early versions of the drills were made in
China so he figured he had better look to those made in the USA. Even then, with some of the most
expensive drill, the darn cheap things, kept burning up. He wanted to know what brand would not burn up.
The comments he got on his post dealt more with
the kind of extension cord he was using, but he then brought up other factors, maybe generator was too
low a rating, even though its meter said 110 v when under load. A return to the forum and questioned how he
could evaluate that generator. Some one then asked the wire size of his extension cords.

He replied the wires were certainly long enough and even an extra 50 feet was available for moving around the site.
So it goes on and on with him not wishing to replace his extension cords, since they were a gift from his father
and his dad never had any trouble with them.

When asked if he had any electrician friends that might help him, he couldn't see any reason, since he did all his
own wiring and they passed inspection. He knew enuff about that subject. Now all he wanted to know was the best electric drill to bu

probably there is a morale here but I am not getting it. What are you trying to tell me?

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

I gave up before and now won't be back.

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

Post of the year, OG!

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
Being ironical does not help me at all
Continuing to recommend (to me and to others) the bentonite solution sounds like "put some Windex" (see "My big fat Greek weeding")
cvg had constructive solutions and recommendations

I still need (remember that I am an engineer too) to understand the solution and it has to be practical for me
Failing to provide that and resorting to ironies does not make you look better.
Some of our teachers in university used to tell us that if you are not able to explain a solution in layman's terms you do not understand the solution or the technology

I hope that now we are even and you will stop giving high fives to each other for the subtlety of your jokes

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

Quote:

I still need (remember that I am an engineer too) to understand the solution and it has to be practical for me

Let me break it down for you:

Your question is like asking what capacitor you need in a PCB without showing us a wiring diagram. We're all just guessing until you show us topo.

Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East - http://www.campbellcivil.com

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
OK here is a link that will give some idea about where I live and the geology of the area

http://trca.on.ca/dotAsset/55381.pdf

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(I hate to get involved. . . )

You seem bothered by poor surface water management. Drop inlets are effective if you have gravity drainage.

You also seem to think it's a ground water problem - i.e., you have a thread about deep well dewatering. O.K., I guess. . . Not sure what that ultimately accomplishes.

Let's say the soil is wet - so what!?! I mean geotechnical efforts need to be weatherproof. Foundation soils get wet. A good engineering program considers the strength of soils (i.e., bearing soils) under saturated conditions. So, if the soil gets wet, that should already be the limiting design constraint.

Let's say the design was not great. What can we do. . . ?

Bummer about standing water. I get that. You seem to have issues on your property that are not easily addressed by the fora. Seems folks are trying though.

f-d

ípapß gordo ainÆt no madre flaca!

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
I fixed what I could and now I have to see if there is anything else that I can fix
I am waiting for a heavy rain to see if the smell comes back in my basement
The weather is very dry around here right now but my wall is still showing wet spots
I am not sure how long it needs to dry and if what I am seeing is due to humidity that is still getting out (maybe accelerated by the excessive dry weather) or what I am seeing is simply a problem that is due to a high water table
I can not detect anything wrong beyond the walls at floor level in basement. I removed the power outlets and tried to see if the wet smells or the "basement smell" comes out through that but no...it is not.

So I do not know that to think right now. I will just have to wait till the weather helps me to isolate the issue here.

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
And here is some extrapolated info regarding the topo of my area
I leave below the 140 m level but quite far from the river
Is to so happens that the profile shown below is near a big street that is close to my house (see the marks on the picture, Lawrence Ave)

Bigger picture can be seen here http://i.imgur.com/NRpi5BO.png

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

so, as I suggested previously, your property may be near a spring. it appears you may have artesian conditions. not much you can do about that except for to waterproof your basement walls and install a weeping tile system with a sump pump to remove the water.

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
How can that happen only on one specific corner right under the patio and for a specific length of the wall with no signs of water or humidity at floor level in basement in that corner ?

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
Let me ask you guys this again: if you suppress the water source for a wet wall like the one that I have, what is a quick an average and a slow time for the wall to get dry again ? Have you come across situations when a wall got back to dry after the source of humiditty was suppressed ? I bed you have not...

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

Assuming your term "supressed" means the water table next to that wall has been lowered to below the floor elevation, as with an exterior perimeter perforated pipe drain enclosed in a filter zone, yes it works. The time for the wall to show drying effect varies, but usually the effect starts right away with no weeping water into basement, followed by gradual drying depending on venting there, etc. In the long run these are dry basements, without the moist smell you note. If the perimeter drain is inside the wall (some guys do this to avoid having to dig outside) you can get drainage affecting outside, but in may not work at all in some soils. That's where test pits or test borings come in.

This improvement also applies to cases where surface water infiltration seeps down and saturates soil alongside the wall (no free water inside) , but then the outside surface is treated to prevent that downward infiltration next to the building (and within the backfill to the wall) which could be an extensive zone. This is not a ground water situation, but effects of surface water that show up as damp wall on inside. Once that flow does not happen, gradual drying results, taking days if it has gone on for some time before. Depends on venting, etc.

The work has to take into consideration lots of factors, not just locally next to the wall. That's where the whole area picture knowledge comes in, not just knowing details next to the problem. Your geology section and that rough note about discharge helps, but just scratches the surface.

If your basement floor has any non-finished areas, consider drilling a hole and then exploring more with a wood auger to see if ground water is near the floor. Don't cut into any pipes!!! It may help a little.

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

You're making this too complicated.

This is almost assuredly a surface drainage issue.

Get a surveyor to shoot grades with 1 ft or 0.5 ft contour intervals, extending into the neighboring parcel, with FFEs on both buidlings, and post an image of that here. The solution will be self evident immediately.

Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East - http://www.campbellcivil.com

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
I am not sure about that.
There is no visible water flow from one property to the other
There is no visible water pooling anywhere on both properties

I am still supecting my patio because it has no gravel base (all built on limestone screening)
I don't buy what oldguy said above, my wall should need more than weeks to get dry. I think that humidity is still trapped either in the limestone layer or in the soil and it will take time till it gets out

One think that I could try is to remove the baseboard in the basement and do something like this

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

OG is talking about non-finished walls where you can see the concrete. Who knows with finished walls, possibly having insulation that holds water. Where seepage was bad, those walls required a full interior replacement after things dry out. Yours look good.

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
If that is the case the source should be eliminated
I regraded the patio and I eliminated the settled areas

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

you said you regraded the patio, but was that done adequately? It should be at least 2% grade for about 10 feet away from the house at a minimum. in fact, you should have that slope on all sides of the house. Roof leads should all extend out and away from the house also. If grading and roof leads are not up to snuff, than I would suggest doing that first. If that does not fix the smell, than at least you have positive surface drainage away from the structure. If this is done correctly, than it will not matter much whether your patio is built on gravel or screening because the water will all drain away from the house. By the way, gravel and screenings both will allow water through to the subgrade. Screening might actually be better base material since it is finer grained and perhaps somewhat less pervious than gravel.

now if you still have water coming in, than do you have a leaking water / sewer pipe within about 20 feet from the house? perhaps even below the basement slab?





RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
BTW it is really interesting that they say that the runoff coefficient for a brick patio is close to 1
TO me that means that no water is getting through. How is this possible? I could see the water falling on the patio and simply vanishing without actually flowing toward the edge of the patio
If I cover the patio with a tarp the slope is good enough to send the water away from the walls, I think that the slope is acceptable.
I am still unclear on how much water a patio absorbs in normal conditions. I n heavy rain it is probably closer to the 1 runoff value because there is much more water than it can absorb in that short time but..if it rains slowly and long term but low volume everything seems to get through

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

Maybe a description of what is meant by "regrading" will help. Then did your "regrading" change this action? "I could see the water falling on the patio and simply vanishing without actually flowing toward the edge of the patio". Sounds like water running through a sieve. Even on a slope that still will occur.

Did that work change this action described by CVG?

"By the way, gravel and screenings both will allow water through to the subgrade. Screening might actually be better base material since it is finer grained and perhaps somewhat less pervious than gravel."

The quantity of water required to cause the wall efflorescence and moist smell is very little. Likely less much than a quart a week reaching the wall

Do the folks that bag up screenings ever provide a grain size analysis? If they come from quarries in the Niagara formation, likely very little silt and clay content. Produce that and it will answer some of these questions.

In Wisconsin I use those dolomite rock screenings as the filter around perforated footing drain pipes. It's porous. The Niagara is here also.

Also, note the sloping lines on the sketch of wall section. Most wall backfill is shoved in in sloping layers and that directs downward seeping water to the wall also.

This (these) discussions sure use up a lot of memory space somewhere.

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

water absorption of the patio is inter-related to several things:

first - does water sit on the bricks and slowly soak in, or run off
second - how much water can be stored in the void space in the gravel or sand base
third - how pervious is the subgrade material (the soil below the screenings)

replacing the gravel or screenings with a concrete base would eliminate most of the infiltration. that is the typical method for commercial grade pavers around here.

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
One of you said that there might be pipes cracked under the slab or something like that
Here is a vie of the nearest pipes. It is the drain for the two toilets.
I am not sure why of if these go under the slab ...I would rather say they must be hidden in the walls
Whatever the case is, I should see no change in the humidity level in the basement if I do not run the dehumidifier.
Recently I started running it regularly amd the smell is mostly gone.
I tested, if I do not run the DH the humidity does not go above acertain level
I do not open the windows in the basement and I keep the door closed in order to see where the smell comes from and if the humidity changes inside by itself
I am seeing a slow increase (2%) but that seems to be all.The weather here in Toronto has been dry and stable.
I think that these would not be possible if the source of humidity is inside the house
On top of this last winter it went away when the temperatures outside stayed very low for a long time
If the source would have been inside then I suspect I should have continued to have smell in basement.

A source located underground on the near by property is excluded, I can't imagine the water traveling such a long distance

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

OG again, trying to keep the discussion here.

In reviewing one of your other posts, I see you say no footing drains.

Reviewing some of your statements and questions, we can be pretty sure the screenings are sufficiently porous to conduct water either by gravity of by capillary attraction.
Chances are the soil below also has some degree of transmitting water from one area to another by capillary action, more or less like a sponge, full depth of wall.

That's where positive cut off of capillary action may have to extend quite deep.

Your questions on one posting:

A couple of questions if I may:
1) is it normal to build a patio the way my patio was built? That is with a 6" of limestone screening and bedding in an all in one layer?
2) is there anything that I can do to improve the drainage of this patio?
3) let's assume that I put the bricks back with the subbase still wet. Is that a good idea/ Will that water ever drain? (remeber there is clay below it)
4) Do I need to remove the massive stones used as edges?
5) My assumption is that the wall got wet because there was excessive moisture in that corner AND because it was in permanent contact with the adjacent subbase which is wet limestone screening. Is this correct assumption?
6) I am now planning to build a buffer or to break the capillarity effect between the wall and the subbase by digging a trench next to the wall and by adding there some insulation. The
trench will be filled with gravel or will be left empty ( I am thinking about some cement blocks.

1) Very common, 2) Looks like the best bet is dealing with the infiltration. One member suggests using a concrete slab. I gave my method, which got a sassy comment.
3) The wet conditi0ns are of no consequence as long as that water can't migrate past a barrier. There is a minor chance of frozen water heaving slightly in winter, That "clay below" likely is somewhat pervious, especially having been shoved back against the basement wall, not compacted. See the sloping lines on the sketch. 4)Probably not. 5) That sounds like the right explanation, but soil below also can be in the picture of moving water in its pores by both gravity and capillary effect..
6) That trench will be another collection zone for water from the surface, snow in winter. It likely will aggravate the problem.

Applying a plastic sheet to the exterior of the basement wall is a way to create a barrier, but it has to be as deep as possible (best all the way to and over the footing.)

If you want to explore the mechanism of capillary action in soil, there is plenty written, especially dealing with plant growth and words like "suction", or "moisture tension". might be looked up. There is a term used for these "Pf" It's been years since my study of that stuff for my Master's, so the label may be wrong.

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

I did a little for you. I see my term was backwards for case.

Here is a U tube video, part of some course.

https://www.youtube.com/watch?v=tcsbqYQr8Vs

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t



This is a shot next to my front door. The house is built for full handicap accessibility,so there is no step at the door.

That means this area has earth fill at that entry grade against the brick wall. The brick sits on a concrete foundation about 12 inches down.
That's 12 inches of earth against the brick, a questionable thing at best.
The plans call for a galvanized sheet metal moisture barrier in the open space between the brick and the interior wood floor framing system behind that.
The house is 13 years old (I have been here 5 yrs) and the engineer developer remarked to me about the barrier. "That's assuming they installed it".

While I can detect no moisture transfer to the wood framing, I decided to do a few things. I dug away all along the wall as deep as the insulation that is against
the concrete. Painted that brick surface with a waterproofing paint. Applied some mastic glue and stuck a sheet of black plastic to the brick.
Painted it where exposed.. Replaced the backfill. Never noticed any exterior efflorescence, but the conditions were right for that to happen.

The earth out in front has been treated out the full area of backfill with the bentonite treatment I have remarked on before, mainly to provide a surface barrier
for any rainfall or snow melt. The site is on a shallow water table, only a foot or so below basement level.

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

Quote:

I am not sure about that.
There is no visible water flow from one property to the other
There is no visible water pooling anywhere on both properties

...which wouldn't matter if it's leaking into the ground, which is exactly what you don't want. You want to be able to see it flow away from your house.

If you refuse to have someone go out there and shoot grade, get your smartphone and video the land between you and your neighbor's houses, as well as the patio, during a half inch storm. You should notice water flowing towards the street or towards the back of your back yard, ideally both. If you do not see water flowing along the ground in at least one of those two directions, then your problem is surface drainage.

Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East - http://www.campbellcivil.com

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

The earlier link is a start as to looking into capillarity, but much more may be involved
at your wall. There also may be an osmotic movement, especially where the efflorescence takes place.

It so happens that concrete is a pretty good osmotic membrane.

However, by viewing the attached videos and looking at the “dry treat ad”
You may have a better handle on working with your situation.

Note a photo in one of the ink videos of efflorescence at a brick wall.

https://www.youtube.com/watch?v=70x98CdErbE

https://www.youtube.com/watch?v=Ph-7tQuIbz4

http://hyperphysics.phy-astr.gsu.edu/hbase/kinetic...

http://www.drytreat.com/

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
Sorry for not getting back with any feedback to you guys
Here in Ontario we are just after a long weekend with lots of things to do at work
I hope to get a few moments later today to comment on the above

many thanks to all of you for the above

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
Quick question: would it work if I drill holes parallel to the wall down to the foundation like showed in the picture below in order to dry up the wall?
I am just trying to determine if the wall is drying up too slowly or there is a constant source of humidity at the base of the wall.

Yesterday and over the weekend it rained. I was away in both cases and I did not have the chance to see how the water is flowing on my patio. I am now running a dehumidifier, a lower capacity one and I can say that it brings the humidity from 60% down to 45% quite fast. That and the fact that probably less and less water accumulates in that corner makes me believe that this is still an exterior problem (wishful thinking smile ) and I might be a little too impatient with this drying up process

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

Og here. My opinion is that drying needs circulation and not much if any with open holes.

If you really want to test your treatment, get out the garden hose and let her run for a while, say a few hours..

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
What would that prove?
I don't have a crack there on that side.
If the crack is not there what else can I test?
If I let it run for a few hours I am going to find out what I already know: if I have increased humidity in soil in that area the wall will get wet

I can see just two other options here in order to see if I am making any progress:
-make some marks on the wall around the wet spots to see if they shrink or they increase after long periods of no rain or shortly after a rain
-try to dry up the spots with a plumber gas torch an see if it gets wet again ..

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

Maybe you can do enough observations, cleaning, etc. to satisfy yourself you know sufficiently enough to make any future modifications.

Looking at some of the reference links sent earlier, and researching "moisture tension" (the Brits use "suction") you may be able to more accurately figure out what is going on.

When I get into a situation involving variable moisture in concrete floors and how it affects glued down flooring, I install devices to measure soil moisture tension in the concrete.

Some can be done with portable meters. In your case I'd look at a meter with a probe. I'd then drill a few holes in the medium I was to test, of the same diameter as the probe.

I have not used those for plants but it sounds like they would do the job.

An interesting result comes when you test real dry stuff. That vacuum effect shows up quickly.

For plants there are some with water in a tube.

It may take sealing at the surface to do the job right. Some of them are pretty cheap, probably available at a green house.

Check out this link as a starter and maybe also search "tensiometers".

https://en.wikipedia.org/wiki/Soil_moisture_sensor

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

OG again with a suggestion for an electrical engineer. Us soils guys do some exploration into the earth with a device called resisitivity.
Some times that is used to find depth to water table or rock.
It measures electrical resistance between probes in the ground. There is no reason that the same general principle cannot be used to monitor moisture content
of masonry or concrete between two buried electrode. Then in the walls perhaps with them in different locations along a possible path for moisture movement.. I'd do some calibrating with the same medium first by varying he moisture content of the medium against the resistance.
Of course one has to take into account solvents in the water that affect the resistance. Osmosis effects also may be involved then. A little research on this also may help
in setting up the procedures. Remember concrete has a bunch of different chemicals in it, some of which dissolve readily. However, I'd still expect to see changes in resistance
mainly due to changes in moisture content. Some of those moisture meters used for growing plants make use of electrical resistance as the basis for the meter.
Maybe the end result will be a paper published about how to evaluate efflorescence prevention methods.

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
Quick update:
-it rained quite heavily...the slope of the patio is good the water drains where I wanted it to.
-the humidity in basement did not increase anymore
-I found the source of smell in the open ceiling of the furnace room. As soon as I started keepng closed that door the smell diminished big time and it is now localized in that room only! I will get back to you with some questions about it


Q: can you take the quotes of your lot using the altimeter function of a GPS ? Crazy idea that I read about on a contractor site smile

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

As someone said before, you guys are WAY overthinking this. This seems to be a clear surface water drainage issue. The patio might be pitched properly, but the clay impervious layer beneath may still be backpitched, allowing water to flow through the limestone screenings down to the clay, and towards the home.

A simple regrading and use of swales would be the likely fix. Possibly a drain at one location should water pond.

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
I beg to differ
This guy (http://www.pavingexpert.com/blocks2.htm) seems to be very good. The site is exceptional for this topic
As you can see below there is no slope for the subgrade
Another detail: for a couple of weeks I had the limestone removed next to the wall all the way to the soil level
It rained but no water made it to the wall via under the bricks and limestone which invalidate your theory
Right now I believe that I have water trapped in the cinder blocks of the foundation walls on that side.
I need to dry out that wall, probably from inside, drilling holes into the blocks and by using a dehumidifier (a professional one)

RE: Lot grading, water percolation & french drain on the property line along the fence..How2 drain t

(OP)
Quick update

It seems that what I see on the wall is not exactly water, otherwise I can not explain this:
I took a hair dryer and I tried to dry up one of the spots
One year ago they looked like this


A month ago they looked like this



The white efflorescence that you see at the bottom of the first picture disappeared by itself (not sure if it is because the rain washed that). The second picture is taken after I fixed the patio

I expected that, by using the hair dryer, I would be able to temporarily dry up one spot and after that I would have expected the humidity to come back and to rebuild the wet spot. This did not happen. The hair dryer had no effect on those spots. I am inclined to believe that they are some sort of salts although I would say a salt should be whitesh not greyish

Any idea why I could not dry up that spot and what are these spots in fact?

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