Any way to repair a perimeter wall?

[RamboII]

I have a 7 year old perimeter wall around my house. Three sides are fine but one side has leaned about 4 inches towards my neighbor's property. I live in the U.S. but the caretaker of the property had a builder come by the property (between CM and Sankamphaene) and he made two suggestions. For 2,000 baht, he could re enforce the dirt at the base of the wall with more dirt. Second, for 20,000 bath, he could make a cut in the wall between each post and put a metal support in place. The last option is to tear the wall down and replace. I will be back in July and would prefer to deal with it then. Does andyone in the Chiang Mai area have a builder with experience in building perimeter walls that they can recommend?

[khmen]

For 20,000 baht to reinforce the wall you'd be better off just tearing it down and rebuilding it, depending on the size obviously.

You'd probably be better off just rebuilding it anyway, if a wall all of a sudden starts "leaning" it's obviously been built pretty poorly.

[DrAndy]

yep, if it is leaning, the posts did not have enough foundation

redo it before it falls over and kills someone

lots of builders could do it, just make sure the foundations are deep enough and wide enough

[RamboII]

There is a difference of around 1-2 feet between the amount of dirt on my side of the wall and my neighbor's land. I would assume that puts pressure on the wall and would require a deeper and probably wider foundation. I have had drainage problems when the walls were originally built (with standing water a couple of feet near the wall after heavy rains). I had concrete trenches built along 3 walls and the water would drain toward the back corner, where it was discharged through a large plastic pipe into the creek behind me. However, there was no drainage along the wall in question and I assume that water going down the wall would start to wash away the dirt below the concrete and possibly cause the wall to shift. I would like to have some temporary supports put in place to hold the wall in place until July, when I can oversee the construction of a new wall. I would contact the original builders (they also built my house and ten apartments and 4 ships next door, and had almost 18 months of steady work) but he is retired and from talking to friends of his, it is unlikely that he would stand behind his work.

[DrAndy]

it is unlikely that he would stand behind his work.

very sensible, he doesn't want to get squashed

[RamboII]

Honestly, in its worst spot, the wall has pulled away about 4 inches. He would probably have to stand there for 5-10 years before getting squashed.

[RamboII]

Just out of curiosity, how long should a properly built wall last?

[DrAndy]

well, some Roman walls are still standing after 2000 years. There are walls in Cuzco that are 500 years old and look like they will last another 5000 years

[Wizard of Oz]

^ don't forget the "Great wall of China"

[RamboII]

My expiration date is around 20 years from now and my wife's 40 years. I'm not looking any further than that.

[RamboII]

Besides, we are talking about Thai craftsmanship, aren't we?

[Norton]

Don't bother with a temporary fix. Rebuild the wall. From what you say about height difference between adjacent property, use columns long enough to allow for at least 1 meter below neighbors property level. At the base of each column have a reinforced footing tied into the column. Have cross beams tied into the columns to act as a foundation for the concrete block. Add drainage on your side of the wall.

Size of the columns, footings and cross beams will depend on height of wall.

[RamboII]

Since I plan on owning the house (or, on my departure, my family), tearing it down and rebuilding makes sense. It would allow a drainage ditch on my side. I hadn't thought of cross beams but, as I plan on doing it on my deck supports (in the U.S.), that's a great idea. I am concerned about the tear down and don't want anyone working on it to get hurt, so it may have to be a controlled tear down. I've got 3-4 months to think about how it should come down, so that shouldn't be a problem.

[DrAndy]

I am concerned about the tear down and don't want anyone working on it to get hurt, so it may have to be a controlled tear down. I've got 3-4 months to think about how it should come down, so that shouldn't be a problem.

you are joking?

if not, just bring a variety of steel capped boots and safety gear when you come back

[RamboII]

yep, if it is leaning, the posts did not have enough foundation

redo it before it falls over and kills someone

lots of builders could do it, just make sure the foundations are deep enough and wide enough

I can take the wall down myself (except for the concrete foundation, as I am allergic to jack hammers and sledge hammers) but having to work 10 feet below the wall, I don't like to take chances. Besides, I seem to be getting mixed vibes from you. Is the wall dangerous or not?

[DrAndy]

without seeing it, difficult to tell

better safe then sorry though

[ootai]

I would agree with Norton that the best thing to do is take it down and rebuild. But considering that it has only lent over 4 inches in 7 years you may be able to solve the problem by good drainage. You won't be able to push the wall up straight again but as there is only about 2 foot difference between the 2 sides. The drainage would stop the water buildup, 2 foot of soil and then 2 foot of water adds up. You also mentioned working under a 10 foot wall so I presume the difference in height is 2 foot so the wall on your side is 8 foot high, why so high?

I have posted a diagram I drew up for another thread on here a couple of years ago. If you have any questions about it please ask and I will try and help.
You said in one of your posts that there was water building up against the wall in question, this does not necessarily "wash" away anything but what it does do is apply a force to the wall higher up the wall where a small force has a longer moment arm length which results in a much larger rotational force being applied to the fulcrum point i.e. the bottom of the post/footing. Think about why you can lift a car with a long lever. Also the water softens the soil surrounding the posts/ footing making them easier to push over.

In terms of pulling the wall down I would suggest you pay someone with an excavator (mako) to tear it down and dig your new footings at the same time.
If the wall has been up for 7 years it will probably last for another 6 months until you get there. However having said that the rate (acceleration) of the wall will be increasing until one day it will "magically" fall over, which is when the centre of gravity gets too far out past the base.
In the diagram if you think the diagonal support is too difficult to build then you could just make a horizontal beam out to twhere the base of the diagonal support is and then when you place the soil on top it provides weight to stop the wall toppling.
The most impostant thing is the drainage so that there is no water build up behind the "retaining wall" section of the wall. If you have ever seen a video of someone puncturing the bottom of a water tank you will have seen the power of static water pressure.

Anyway enough of the engineering bullshit, good luck with wehatever you decide to do

[hillbilly]

My experience has shown if the wall leans, tear it out and rebuild.I have seen many makeshift repairs. None of them work long time...

[DrAndy]

agreed, not that expensive anyway

[Joe66]

well, in 6 weeks, the rainy season could destabilise this part of the wall much more,

you should take care, that the humus layer of your land is not floating away,
leaving big holes at the wall,
and make the problem worse.

a few packs of concrete might help against the erosion

[RamboII]

Like I said, there is a concrete drainage system. Also, on the back side, where there is a creek, there is a thick layer of concrete against the back of the wall, about 2 foot wide. My only concern is the one wall. My wife will be there by May 30 and there is a caretaker staying there until then, so I'm not overly concerned that it might fall before then. Besides, I live on a private road and the adjoining property is a farm, so the chances of the wall falling on anyone is slim to none.

[BillH52]

Built our wall about 4 yrs ago. 20,000 is approx 1/4th the cost of ours, but varies by length, of course.
Thinking the right way would be to have an experienced & reliable wall guy rebuild it. Somebody who would stand behind his work for a reasonable period of time.

[DrAndy]

Somebody who would stand behind his work for a reasonable period of time.

I suppose that would be the best way; if it fell down it would fall on him

[VocalNeal]

Thinking out loud

Take down the wall to the height of the 2 feet of soil inside the wall.
Dig out the soil and pour in concrete to make a new foundation using the 2ft of wall as a form and include some tie backs.
Build a new wall on top of the new foundation.
This eliminates problems with the stream.
The new wall does not have to hold back the soil as it is held by the new foundation?

[RamboII]

Thanks for all the advise. Its about a month until my wife and kids leave for the house, and about 2 months before I will be there for a month. On my side of the wall, there is a garden area about 3 feet out and then the concrete driveway. There is also a garage at the start of the driveway with a brick wall between the perimeter wall and the garage. The bricks had separated from the perimeter wall and it is that separation which was about 2.75 inches two years ago. I don't think that I could run steel supports to anchor the wall from my side, since the driveway and the garage are so close to the wall. So, the logical thing to do at this point is to have the wall completely torn out, dig the foundation deeper and put a drainage system both inside the wall and a concrete ditch on my side of the wall, which ties into the concrete drains that surround the wall on my property and drian out on the backside to the creek behind me. While the wall can be torn out when my wife is there in June, I would want to talk over the details and be there for the actual work. I guess I will have to leave it to my wife to ask around and try to get several bids. I wonder how I'm going to get rid of the debris left over from the original wall? As a last resort, I could have someone haul it to my other property near Saraphi. Neighbors are always dumping concrete debris on the dirt road to minimize washing out the road during rainy season.