Sinking ground

[nullx8]

Guess that is a common problem,

The house is about 5 Years old, workers just dumped the construction junk arround, filled up with sand and put a thin layer of Ground on top.

Now, few years later, the rain washed out the ground, and some large gaps show, lots of animals found a new home in the gaps.

Anyone knows some trick how to close the holes without dumping truckloads of ground ?

As this gonna be a expensive mission.

[Gonsalviz]

Truckloads of ground are not really expensive if you get a Thai to set it up. Maybe like 200 Baht a truck. And they bring a tractor to level it for 50Baht

[Gonsalviz]

In Isan it is 150 baht a truck plus 50 baht more per truck to level it. Not really expensive.

Don't know where you are but if in tourist area it will be maybe 275 Baht a truck.

[elgordo38]

In Isan it is 150 baht a truck plus 50 baht more per truck to level it. Not really expensive.

Don't know where you are but if in tourist area it will be maybe 275 Baht a truck.

The price per truckload is climbing. My g/f has some land she wants to top up and she is being quoted up to 300 bahts a load and your lucky to get a full load. Skimming loads is common. As this is the top layer of soil where future planting will be done the quality of the ground is questionable as well. You have to be standing right there checking or you could be short changed. It always amazed me when living with my previous g/f whose mother owned a store that she would count deliveries 2 and 3 times before letting the delivery guy go. Edited November 28, 2015 by elgordo38

[AlexRRR]

Once you get that top soil in if you don't want any more issues put some plants in to help hold it there, you got erosion either from the lack of plants or/ and water running off your roof going where ever it wants, spouting and a few down pipes running into underground pipes to take the water away from your house might be an answer as well.

[nullx8]

I put stones where the water falls down to prevent the wash-out,

The main problem is that there is a 50cm gap under the house now, and the ground arround the house simply moves there,

The cost of 300 is in Bkk?

I asked arround a little bit, but they came up with much larger numbers.

Strangely also all of them asked about the size of the land and ignored my request in qubicmeters (odd thing)

[xen]

I would agree with Alex about having a look at drainage as well - it would be a good time before you add more top soil . You will need shale to fill the already sunken , or eroded areas and this time compact it in perhaps 200 mm levels then add your top soil . The sinking soil could also be due to composing vegetation buried too ( means methane gas could be trapped in the sub soils too but that normally will not be a problem apart from causing some shrinkage ).

Sounds like pretty sloppy builders . Is the house built on a slab or piers coincidently?

[Pib]

Last year Mahidol University in Nakhon Pathom province/just a few kilometers west of Bangkok was undergoing some new facilities construction (and they still are) which required many, many truck loads of dirt to be bought in. Rather than trucks just arriving, dumping, and leaving to go get another load of dirt all the trucks had to go through a checkpoint where each truckload was counted and examined before being allowed to continue through the checkpoint and dump its load. By examined I mean people would climb=up on top of the dirt load and push down metal rods to extract samples...they did this also from the sides when possible...this was done to evaluate the quality of the dirt. Sure they could have don't this after the dirt was dumped but if it failed examination it would have to be reloaded which would slow down other work like the bulldozers which was pushing around the dumped dirt and probably resulted in an argument...and maybe they did do another eyeball check after dumping. But it was obvious they were not going to accept just any old dirt to build their facilities, roads, and lawns on...they also always plant many trees along their roads/around their facilities which would need quality dirt to grow well.

[AlexRRR]

I put stones where the water falls down to prevent the wash-out,

The main problem is that there is a 50cm gap under the house now, and the ground arround the house simply moves there,

The cost of 300 is in Bkk?

I asked arround a little bit, but they came up with much larger numbers.

Strangely also all of them asked about the size of the land and ignored my request in qubicmeters (odd thing)

With a 50cm hole under your slap i would be getting it under pinned....that is filled with concrete, you will need someone who knows what there doing.

Rocks or stones only stop the falling water from digging a deeper hole, the erosion is caused by the water washing your loose soil away.

Lot of Thai house I've seen don't have spouting and downpipes let alone underground pipes to take the water away, if you don't want to do this which every house in Australia has on repairing that area get a concert path put over it once its been under pinned and compacted.

[Thorgal]

Can you provide a picture? I think that your problem can be solved by :

- mud jacking/filling

- bi-component PU foam jacking/filling

Depends where you live to find a company who can do the service.

It's common practice in area's/house with high rain amounts and, combined in some cases with poor backfilling practice in early stage of construction.

Here a random overseas company for info, about frequent asked questions.

http://polytek360.ca/faq/

Edited November 30, 2015 by Thorgal

[nullx8]

Pu foam is a great idea!

But it will be at great cost,

Basically there is a very large pool under the house, and now everything arround starts to follow.

I dont really worry about my walkway is sinking, i just want the soil to stay where it is,

The concrete idea is also good, while on it maybe build a basement too and give the concrete a reason

Edited November 30, 2015 by nullx8

[AlexRRR]

i don't see any 50cm hole....50 cm is 500 mm or half a meter.

Its a good idea you get an engineer out to inspect your property since your so concerned better to spend money on a professional who knows what there on about he can come up with a fix for you.

Its common to back fill around the permitter of a concrete slab, its also common in most places to put in something to take the water away from your house. Also stopping water running from higher ground towards your house.

[kannot]

It may well be built on piles? in which case it wont be going anywhere

[Chilon]

I have a related problem similar to the OP’s caused by rainwater runoff from the house. In my case the water has built up behind a block wall parallel to one side of the house at a distance of about 2metres . This wall separates the house from the adjoining property. The adjoining property is lower which has exacerbated the problem.

As a consequence the wall has bowed out and the ground next to the house, which has a tank on a slab upon it is in the process of collapsing. No problem with the house foundations yet but unless the problem gets sorted it will only be a matter of time. Photos attached.

I’m thinking of moving the tank, perhaps breaking up the slab and partially excavating behind the wall to relieve the pressure then trying to straighten the wall (somehow ) before shoring the wall up with concrete piers. I could then backfill, put some weep holes in the wall, pour a new slab and then install appropriate guttering to take the rainwater away so it doesn’t cause the problem to reoccur.

If anyone has any advice on how to go about fixing the above I would appreciate their views, in particular the easiest way to straighten a wall. If I could do that without excavation then perhaps the PU foam solution as mentioned by Thorgal above might solve the other issues ( if it is available where we live)