Building a new house in Isaan

[HighPriority]

15 hours ago, Encid said:

 

The sample collection technique was simply to run the submersible pump for as long as it took to fill the water tank, then wait about 5 minutes, then collect the samples from the overflow pipe.

The sample bottles were new, just-emptied 1.5L mineral water bottles bought from the local Lotus's - 3 in total.

It would seem that you are also sampling the water that has been sitting in the tank ?

I’d have thought that filling as directly from the bore as possible would have given more exact results ? ie, run the pump to pass the water that that had been resting in whatever length of pipe applied and then fill your sample bottles.

 

 

[Encid]

2 hours ago, HighPriority said:

It would seem that you are also sampling the water that has been sitting in the tank ?

I’d have thought that filling as directly from the bore as possible would have given more exact results ? ie, run the pump to pass the water that that had been resting in whatever length of pipe applied and then fill your sample bottles.

 

Perhaps I should be more clear... the pipeline was first flushed with new bore water into the pond while we emptied the water tank.

We then filled the tank with new bore water and let it overflow for 5 minutes before taking the sample.

We tried to avoid any possibility of sampling "old" water.

 

[Muhendis]

20 minutes ago, Encid said:

Perhaps I should be more clear... the pipeline was first flushed with new bore water into the pond while we emptied the water tank.

We then filled the tank with new bore water and let it overflow for 5 minutes before taking the sample.

We tried to avoid any possibility of sampling "old" water.

 

Looking at the results of the lab. report I would say high levels of precision are not so important.

Any contaminants which have been picked up from sources other than the bore hole are listed in with the bore hole water. It does not matter if they are from the hole or minimally from the surrounding environment, the water is safe but a bit hard.

[unheard]

19 hours ago, Encid said:

We found plenty of good clear water at only 27 metres depth, but we went down a few metres more just for good measure.

Make sure the bore is properly sealed with a concrete pad to prevent surface water contamination.

A good sealing bore cap is also a good thing to have. They tend to just cover it with a plastic disk leaving visible gaps all around.

[dinga]

On 12/17/2022 at 6:44 PM, Encid said:

You are correct... after a bit of research it seems that you should trim the grass to 30cm above ground level initially after 4 months of planting.

The second cutting should be done just before flowering starts in the second year.

After that you can just leave it to grow, unless you plan on harvesting the whole plant for the essential oils found in the root legumes.

 

We are not planning to harvest as we want the erosion prevention measures provided by the root systems.

Excellent - thanks (have just trimmed the grass as outlined).  I read elsewhere that the vertiver should be initially fertilized with chicken poop (wish I knew that at the time).  Should I fertilize now or is it better to wait until just before the Wet Season (say May)????  Any tips/traps as chook poo is pretty strong???

[Encid]

On 1/15/2023 at 11:39 AM, unheard said:

Make sure the bore is properly sealed with a concrete pad to prevent surface water contamination.

A good sealing bore cap is also a good thing to have. They tend to just cover it with a plastic disk leaving visible gaps all around.

Thanks to that tip... I will check it out next time we visit the farm.

 

I just got back so the next trip is likely to be another week or two away.

[Encid]

On 1/17/2023 at 1:37 PM, dinga said:

Excellent - thanks (have just trimmed the grass as outlined).  I read elsewhere that the vertiver should be initially fertilized with chicken poop (wish I knew that at the time).  Should I fertilize now or is it better to wait until just before the Wet Season (say May)????  Any tips/traps as chook poo is pretty strong???

I just answered that one for you in the other topic. 

[Encid]

Well we just got back from a couple of days visit to the farm.

 

This time I took along a laser level and a tape measure so was able to determine elevations which I then forwarded to our architect and builder.

I used a datum of the top of the middle of the concrete government road at the entrance to the farm, and used Google Earth to determine the RL (Relative Level).

Results as follows:

 

Elevation of top of government road = RL 168.000m

Elevation of bottom of concrete wall = RL 168.180m

Elevation of top of concrete wall = RL 170.180m

Elevation of top of filled land = RL 169.540m

Elevation of land at pond = RL 168.520m

 

RL 168.200m is the highest recorded flood level in the area, so we should be pretty safe.

 

 

 

 

 

[Encid]

In case you are wondering about all those concrete rings on the property... no, we are not going to build a shedload of toilets that need concrete ring soakaways!  

 

We want to reclaim some of that over-excavated land behind the 2m high concrete slat wall... caused by an over-opportunistic back-hoe operator who coaxed my naïve and grengjai FIL into doing it some months ago.

 

Currently it is 4.6m from the wall to the top of the slope (x 60m long) and we want to get back as much as we can of that area.

 

So the land just inside the wall will first be levelled using a small loader or bobcat, then a 5cm thick concrete base poured to match the existing height of the wall foundations, then the rings will be placed on top of each other (5 x 40cm high) on the concrete base so they will be the same height as the existing concrete slat wall. Plastic sheeting will be placed under the bottom layer of rings, then pulled up the sides to the top ring to act as a water barrier. The land will then be filled up to the rings, then the rings filled with land too.

 

We will add slotted PVC pipe drains covered with crushed rock on the fill side of the plastic sheet to act as a French drain to take excess water away to the farm.

 

It is a relatively inexpensive but ugly way to build a retaining wall, but in our case you won't see it because it will be hidden by the concrete slat wall.

 

We plan to plant different coloured bougainvillea in the top of each ring, which will add a ton of colour to the top of the wall and eventually cascade over the side. Being a spiny plant it will also be a good security measure because anyone trying to climb over that wall in the future will be bleeding profusely. 

 

[Encid]

20 hours ago, Encid said:

We want to reclaim some of that over-excavated land behind the 2m high concrete slat wall... caused by an over-opportunistic back-hoe operator who coaxed my naïve and grengjai FIL into doing it some months ago.

 

Currently it is 4.6m from the wall to the top of the slope (x 60m long) and we want to get back as much as we can of that area.

This is a better photo of the land we want to reclaim...

 

 

After the concrete ring retaining wall is built and the void filled, we will have an additional 216 sq.m. (or 54 talang wah) of usable land.

 

[Encid]

Well yesterday the workers were there with their machinery and dumpy level to prepare the land for the concrete slab that the rings will sit on.

 

 

 

[Encid]

And today they are pouring the concrete...

 

 

[Encid]

And later in the afternoon...

 

 

 

 

[sometimewoodworker]

On 1/19/2023 at 5:10 PM, Encid said:

So the land just inside the wall will first be levelled using a small loader or bobcat, then a 5cm thick concrete base poured to match the existing height of the wall foundations, then the rings will be placed on top of each other (5 x 40cm high) on the concrete base so they will be the same height as the existing concrete slat wall. Plastic sheeting will be placed under the bottom layer of rings, then pulled up the sides to the top ring to act as a water barrier. The land will then be filled up to the rings, then the rings filled with land too.

 

We will add slotted PVC pipe drains covered with crushed rock on the fill side of the plastic sheet to act as a French drain to take excess water away to the farm.

 

It is a relatively inexpensive but ugly way to build a retaining wall, but in our case you won't see it because it will be hidden by the concrete slat wall.

Just one, very important point, do not underestimate the ability of the earth to move your concrete rings and to then push you concrete slatted wall out of plumb. I would not under any circumstances allow anything between your concrete rings and the wall. Do not underestimate the ability of earth, stone or sand to push your wall over.
I have had experience of a well built wall being almost pushed over by numptys that way, to this day we have to have props against the low side.

[Encid]

3 minutes ago, sometimewoodworker said:

Just one, very important point, do not underestimate the ability of the earth to move your concrete rings and to then push you concrete slatted wall out of plumb. I would not under any circumstances allow anything between your concrete rings and the wall. Do not underestimate the ability of earth, stone or sand to push your wall over.
I have had experience of a well built wall being almost pushed over by numptys that way, to this day we have to have props against the low side.

Currently the plan is to have a 20cm gap between the back of the wall posts and the leading edge of the concrete rings.

Something to monitor in the future.

[sometimewoodworker]

5 minutes ago, Encid said:

Currently the plan is to have a 20cm gap between the back of the wall posts and the leading edge of the concrete rings.

Something to monitor in the future.

I would be inclined to add something like a low 15cm concrete block between the rings and beside the uprights or some very thick lengths of rebar hammered well down into the ground as stops.

[Encid]

24 minutes ago, sometimewoodworker said:

some very thick lengths of rebar hammered well down into the ground as stops.

I like that idea. 

1.2 m long x 1"dia rebar hammered into the land side of the concrete slab, and the bottom ring placed over it will keep the load off the concrete slat wall.

 

Just like this...

 

[sometimewoodworker]

58 minutes ago, Encid said:

I like that idea. 

1.2 m long x 1"dia rebar hammered into the land side of the concrete slab, and the bottom ring placed over it will keep the load off the concrete slat wall.

 

Just like this...

 

That’s exactly what I was thinking of, one further point don’t forget to add some rust prevention paint to the rebar. It’s probably easiest to use a trough and soak the bar a couple of times. The paint will mostly get rubbed off as they get hammered in but if you use deformed bar some will stick, I would also use something a bit longer than 1.2 M as you might not have much left above ground, I would test how far the bars can be whacked in before deciding the length.

 

Also doing it with those will allow you to stake all the rings.

[Encid]

9 minutes ago, sometimewoodworker said:

That’s exactly what I was thinking of, one further point don’t forget to add some rust prevention paint to the rebar. It’s probably easiest to use a trough and soak the bar a couple of times. The paint will mostly get rubbed off as they get hammered in but if you use deformed bar some will stick, I would also use something a bit longer than 1.2 M as you might not have much left above ground, I would test how far the bars can be whacked in before deciding the length.

 

Also doing it with those will allow you to stake all the rings.

We have another day to do some tests as the concrete is curing then the plastic sheet and rings will be placed tomorrow.

Getting the bars painted will take time, but I hear what you say... maybe spray painting will be a quick option as opposed to finding and using a trough with limited time and people standing around.

I better get onto it right away...

[Encid]

My builder has come up with a good alternative using available (surplus) rebar. 

 

The first concrete ring will be placed on the plastic sheet on top of the concrete base, 30cm away from the edge of the slat wall.

Holes will then be drilled in the concrete base and RB9mm rods inserted in the holes.

Then a 10cm layer of concrete will be poured into the ring, covering the rods (so they won't need painting).

This will effectively anchor every base ring from movement.

 

 

Having performed the land survey the other day using a laser level, it is evident that the amount of rain we have had over the past year has resulted in significant land settlement... which is a good thing.

We have had a settlement of some 60cm of the original 2m high fill, which is about 30%.

 

Also it means that our retaining wall will only need to be 4 concrete rings high, not 5.

And the tops of them will not be visible from the other side of the concrete slat wall (public viewing from the road).

Another good thing.  

 

[sometimewoodworker]

13 hours ago, Encid said:

Having performed the land survey the other day using a laser level, it is evident that the amount of rain we have had over the past year has resulted in significant land settlement... which is a good thing.

We have had a settlement of some 60cm of the original 2m high fill, which is about 30%.

That probably means that you are unlikely to see much more seiilement as long as the fill was compacted when it was deposited, as 30% is around the amount of air that is usually included in the fill. If the fill wasn’t throughly compacted you might expect up to another 20% drop.

[Encid]

Work on the retaining wall is progressing well in cool and overcast conditions...

 

 

 

Note the 9mm rebar rods inside the inner wall of the rings in the photo above?

4 rods per ring to help prevent axial movement.

It looks like they forgot the paint though... 

The rings have also been grouted together.

Next step is to lift up  the plastic water barrier and fix it to the top of each ring stack and back-fill with land up to the existing land level.

After that the rings will be back-filled with land.

 

I am not sure whether to fill the 30cm gap between the concrete slat wall and the ring retaining wall... my builder wants to as he is concerned that it will become a haven for snakes if we don't. 

 

Thoughts?

[Muhendis]

31 minutes ago, Encid said:

Work on the retaining wall is progressing well in cool and overcast conditions...

 

 

 

Note the 9mm rebar rods inside the inner wall of the rings in the photo above?

4 rods per ring to help prevent axial movement.

It looks like they forgot the paint though... 

The rings have also been grouted together.

Next step is to lift up  the plastic water barrier and fix it to the top of each ring stack and back-fill with land up to the existing land level.

After that the rings will be back-filled with land.

 

I am not sure whether to fill the 30cm gap between the concrete slat wall and the ring retaining wall... my builder wants to as he is concerned that it will become a haven for snakes if we don't. 

 

Thoughts?

Snakes eat rats so bring 'em on. I have quite a few snakes so the rats go and live else where which is good for my rice storage barn.

Your builders concern is probably a reflection of his (and Thai villagers generally) fear of snakes. 

[Encid]

41 minutes ago, Muhendis said:

Your builders concern is probably a reflection of his (and Thai villagers generally) fear of snakes. 

Funny you should mention the (general) Thai fear of snakes... yesterday morning my wife came running into the house screaming "snake... snake!"

I asked her where it was and she said in our (external Thai) kitchen.

I grabbed the longest object near at hand, which happened to be a 50cm long plastic spoon that I had been using for stirring up paint, and headed bravely into the kitchen.

Once inside, I looked down and around all the corners... you know, the places snakes usually retreat to if it gets noisy!

Sure enough, curled around our water isolation valve was this little beauty... a harmless Banded Kukri... about 50cm long.

I think it was more scared than my wife... 555.

 

 

Anyway I used the spoon handle to gently ease him out of the kitchen and towards the front gate and garden... only about 5m away.

I don't think he'll be back!

 

 

Anyway, back on topic... so that's 1 vote for leaving the "snake gap" open.

Any others?

[Muhendis]

1 hour ago, Encid said:

The rings have also been grouted together.

Will there be an escape route for the water between the pipe wall and the slat wall?

Or are you planning for a fish farm perhaps.

[farmerjo]

2 hours ago, Encid said:

Work on the retaining wall is progressing well in cool and overcast conditions...

 

 

 

Note the 9mm rebar rods inside the inner wall of the rings in the photo above?

4 rods per ring to help prevent axial movement.

It looks like they forgot the paint though... 

The rings have also been grouted together.

Next step is to lift up  the plastic water barrier and fix it to the top of each ring stack and back-fill with land up to the existing land level.

After that the rings will be back-filled with land.

 

I am not sure whether to fill the 30cm gap between the concrete slat wall and the ring retaining wall... my builder wants to as he is concerned that it will become a haven for snakes if we don't. 

 

Thoughts?

Bit late to the party but love your wall.

Did you ever consider gabien baskets versus the rings and wall.

I priced some the other day at 650 baht for a cage 1 metre long by 1 metre wide by 1.5 metres high.

Our local quarry quoted 170 baht for 75mm plus size rock.

I presume per ton(not cubic metre) as sent the wife into ask.

[sometimewoodworker]

5 hours ago, Encid said:

I am not sure whether to fill the 30cm gap between the concrete slat wall and the ring retaining wall.

Don’t. It will fill up in time anyway, but I can virtually guarantee that if they try to fill it they will damage the slat wall.

[Encid]

20 hours ago, Muhendis said:

Will there be an escape route for the water between the pipe wall and the slat wall?

Or are you planning for a fish farm perhaps.

There already is a 20cm dia PVC drain pipe under the short section of slat wall at the southern end... we put that in months ago to drain the water coming down the slope away to the farm... and yes, there was a lot of water that needed to be drained last year.

 

And I'm not really anticipating a lot of rain water will accumulate in the void... it's only 30cm from the back of the slat wall to the edge of the concrete ring.

[HighPriority]

How deep is the gap going to Be ?

My only concern is that if you can drop something down there, you will... ????

 

[Encid]

20 hours ago, farmerjo said:

Bit late to the party but love your wall.

Did you ever consider gabien baskets versus the rings and wall.

I priced some the other day at 650 baht for a cage 1 metre long by 1 metre wide by 1.5 metres high.

Our local quarry quoted 170 baht for 75mm plus size rock.

I presume per ton(not cubic metre) as sent the wife into ask.

Thank you.  

 

If you go back further in this topic you will see the reasons why we are where we are now... initially our neighbour complained to the local pooyai baan that land from our fill exercise was spilling onto her land, so one morning my inlaws had a visitation by a horde of people including our pooyai baan and it was agreed to excavate the fill back from the boundary until the chanote survey markers were uncovered. But instead of firstly  digging by hand to reveal exactly where the marker were, then excavating back just 1m or so, the back hoe operator excavated back some 4-5m and my FIL accepted it.

Once the survey markers were revealed (they were only just covered by a couple of cm of dirt) our troublesome neighbour accepted it and left, so the pooyai baan accepted it and everyone left except the opportunist back hoe operator who wanted payment of course.

 

We looked at fence/wall options and the concrete slat wall was the cheapest and quickest to build (with local labour - see also earlier in this thread) and we ensured that it was built just inside the chanote survey markers without disturbing them, and it now serves as a big middle finger salute to our formerly troublesome neighbour.

 

When I first started laying out the plans for our guest house and main house I measured the land as best as I could without using a theodolite (I used a CAD drawn protractor on A4 paper to measure angles, and a 30m tape measure) and realised that if we reclaimed the over-excavated land we would have an additional 216 sq.m. (or 54 talang wah) of usable land... and that's excluding the concrete ring retaining wall.

 

I did look at the possibility of using gabion baskets, but they would have been too expensive as there are no quarries anywhere near us for hundreds of km. The nearest rock quarries would probably be in Saraburi, so the cost of transporting the rocks to our site would have been excessive.

It would also have been a shame to hide the gabion wall after completion by covering it up with land fill... they do look wonderful.

 

So that's why we are where we are today.