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Old 10-14-2006, 04:22 AM
huh huh is offline
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Join Date: Oct 2006
Location: Lubbock
Posts: 255
well now that I know where you live I will offer more

first while I do know a bit about soil I am not an engineer...have taken a few courses though

first it is hard to tell if you have gutters, but it looks as though your neighbors don't which makes me believe you do not as well...they would be a good idea at least for that side of the house

it has been a LONG while since i plied the shores of lake Conroe but I believe by "clay" you have more the black gumbo clay than the redish correct?

how old is the house?.....the houses look 7-9 years old but the dock looks about 12 years old....i ask just to get an idea of how long that wall has been in place

do you know how deep the foundation is poured for the house? that would be the FIRST thing I would find out

how long do you plan to own the home....i ask to get an idea of what type of work you are prepared to do to the wall

as for how long it takes water to get through clay...in your area forever/fast......by this i mean that ground is probably ALWAYS damp a few feet down....and if it is not it is probably bone dry and cracked....then when wet again the clay is wet, but water probably never "flows down" very far.....the soil just gets wetter and expands.....which im sure you already know is what happened down at the end of the wall...and the water probably never weeps from the holes because the soil just holds it

again I AM NOT AN ENGINEER, but I did grow up in Houston and know all about shifting slabs, black gumbo soil, and a bit about Lake Conroe too

I hate to say this, but if it was me that wall would be DOWN and a new properly build CONCRETE or otherwise STRUCTURALLY sound wall would be build in its place with whatever facade covering it for looks that you like

I say this based on what I see at the end.....that wall has NO structural support of any kind...if it is over 5 years old I am surprised it held this long....there is NOTHING behind it to actually contain the movements of the soil that i can see

the sketch you drew might work in some areas, but in my LAYMANS head it will not work where you are at....the forces at work on the area of ground between your house and the wall are spread over the entire area....in other words while your idea may prevent the area right in front of the wall from becoming soaked in a heavy rain/run off event it will do little to stop the forces behind that area....and not to sound super negative, but I would even have concerns of the area under the drain drying out in between small rains and then with a LARGE rain event it becomes rehydrated from water soaking in up closer to the house and flowing towards the wall and it actually adds to the heaving that is working on the wall

really in my NON-EXPERT opinion what you are up against is not water soaking down and eroding and pushing the wall or undermining it....you are up against soils that expand and contract a great deal

and in my opinion the only way to handle that long term is to have something that can resist that movement....like a concrete wall or a well build wall of railroad ties or a concrete reinforced cinder block wall....something that will not be pushed around by the movements of the soil

there are a lot of options...the least expensive I would consider would to be dig down on the lake side of the wall 3-4 feet and then maybe auger down another 3-4 feet deeper every 5-6 feet of length and pour a new concrete wall about 1 foot thick all the way up to slightly above the rock wall that is there now.....with form boards on the lake side and the existing rock wall as the back side of the pour....you could extend the existing (not doing much drains) that are in the rock wall on out to the other side of the new concrete wall......then again put on what ever facade you want to the new concrete

the other option is to do the same except on the house side of the rock wall.....with the ground as one form and the rock wall as the other....but I bet this would blow out the rock wall if not careful pouring the concrete...and really would be a LOT more work than the first idea....and you would need to dig down BELOW the bottom of the existing rock wall to get into soild ground....otherwise it is just a concrete wall being pushed over behind a rock wall that is being pushed over

the last option is to RAPIDLY tear it ALL out during a dry time and pour a new proper concrete wall or rail ties ect.

the key to me is to get something structural down ANCHORED into the ground below the lake side grade....otherwise that large mass of soil will just start to push on whatever is build new in front of it

again let me stress these are the opinions of someone that lived in the area growing up and knows about how the soil acts down there....not an engineer....i am all for saving money too, but BOY that is not much room between the house and that NON-STRUCTURAL wall...and I doubt that the soil between the house and the wall was "undisturbed" before the wall was built so the soil is less stable than normal

and again in my opinion you are fighting the ENTIRE area of soil between the house and the wall...not just the area near it....and concreting over it or otherwise preventing more moisture entering that soild area could be just as bad because the soil will move when dried...and if it ever was to get wet again it would MOVE AGAIN A LOT....and it would dry around your foundation as well

with the SMALL area between a NICE house slab and a wall that has no support holding back a lot of ground.....the height of the wall....and the type of soil I would strongly consider getting a true soils engineer out there

yes they cost money, but you would be surprised how much they can SAVE as well from doing it wrong....and if you are a good handy person I see no reason YOU could not follow the specs laid out by said engineer and do it yourself and still save some money

hate to rain on the parade, but that is how I see it.....if an engineer is out and too expensive then I would dig the trench on the lake side......auger down further for deeper "piers" and pour a 1' thick reinforced wall up to the top of the rocks and slap on a new facade....and I might look into the fibre reinforced concrete was well to prevent having to use so much or possibly any rebar....and before I poured I would put a thin vapor barrier on the lake side face of the rock to keep moisture from coming through the new concrete and poping any mastic off holding on the new facade

Conroe is a great area, but I never liked the lake much...when I was young i did not like to fish and Conroe had too much hydrilla to ski on the open spots...but great fishing... and then when I learned to like fishing they had killed the hydrilla and a lot of the bass with the stupid grass carp

and damn lake Conroe was crowded in 1980s can't imagine what it is like now....but still a great area and when you are living on the lake you go out on the "off times" and leave the weekends to the amatures

as new as the houses look I can't believe they allowed that tall of a non structural wall to hold back that voulme of MOVING soil with such a small distance to the house slab.....unless the slab has 4'+ deep pours 1'+ wide on the slab edge and deeper piers every so many feet

im sure my answer was not what you are looking for, but a few years back I went to a friends wedding in Houston (im from West Houston) and ran into some old friends who had finally decided to LEVEL their existing house in Walnut Bend and build new because they loved the area, but got tired of practically having the foundation guy move in with them over 10-15 years....if something is not build right do deal with the soils down there it is near impossible to "rig it up" so that it works right

good luck hope this helps....some

Last edited by huh; 10-14-2006 at 04:31 AM.
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