House Extension to "Baan Thai" Chiang Mai

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Re: House Extension to "Baan Thai" Chiang Mai

Postby Sometimewoodworker » Thu Jun 04, 2015 9:03 pm

http://earthquaketrack.com/v/asia/recent?page=2
Will help

So far I've never felt an earthquake in my time in Thailand, I must be lucky in where I live.

At the moment I get about 1 a day here though I've only really noticed about 3 or 4, in the last year and they are the ones that have knocked things down in my apartment, stopped the trains or lifts.
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Re: House Extension to "Baan Thai" Chiang Mai

Postby eyecatcher » Fri Jun 05, 2015 4:58 pm

Day 5

We are preparing for the first concrete delivery today. :D Just a couple of cubes of weakmix connie and sand to base out the footing pits. We re-set all column positions yet again; and I heard one of the workers announcing “farang check center again hahah” It annoys me to hear that; but you can’t check often enough. My roof is complicated. I have designed the main pitch at 42 degrees and the shallow overhangs at 21 degrees. The roof of my existing house will meet the roof of the new house with an aluminium gutter picking up two roofs. If my columns are not “cock on” then there could be serious implications at roof level.

We have 14 pits taking up about 50% of the site area. They are already slowly filling with ground water/seepage and need to bail out just prior to the connie delivery.
Access to most pits is awkward to say the least. They are trying to set up walk boards across the open pits, and I am surprised no one has actually fallen in the water yet.
DSC_0220.JPG
bailing out the footings
DSC_0224.JPG
DSC_0226.JPG


The team spent a furious hour bailing out the water from the footings before the concrete arrived. Of the 14 pits the extended split water pipe chutes could only reach 9 footings so the last 5 were filled manually by a chain of buckets. I had an appointment by this time so surely nothing can go wrong; its 4pm the last bit of connie from the wagon and day over. Yes I can leave them for a short while can’t I?
DSC_0230.JPG
1st concrete pour
20150529_153312.jpg
20150529_153319.jpg

2hrs later I returned…..by the way; the answer was NO I shouldn’t have left them. :?
They had for some strange reason started to set up 3 of the column cages. I wasn’t too happy with this as it looked to me like they were making use of the extra quarter/half cube of concrete so rushing to set up the columns. If this is weak mix concrete they have used to complete 2 of the footings then for sure we will be starting again. I need to check the Steng rating.
We measured the column centres prior to the original dig; I checked them again. During the dig all the string lines disappeared. They were set up again to peg out the centres in the base; again they disappeared to get the concrete in.
Now for some reason I can see even without a tape measure that 2 of the 3 are at least 100mm out of position. :lol: :( So why the hell didn’t they continue checking. :?:
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Re: House Extension to "Baan Thai" Chiang Mai

Postby Roger Ramjet » Fri Jun 05, 2015 8:54 pm

eyecatcher wrote:Now for some reason I can see even without a tape measure that 2 of the 3 are at least 100mm out of position. So why the hell didn’t they continue checking.

Don't get disheartened now, just keep checking everything. I checked and double checked everything. You shouldn't have to do it, but TIT and it takes a long time for change. I bought the foreman a cheap laser light (1,000 baht) and that solved that problem as he had a new toy.
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Re: House Extension to "Baan Thai" Chiang Mai

Postby eyecatcher » Sat Jun 06, 2015 9:31 am

Day 6
I couldn’t sleep last night; I told the Mrs about it and she just wants me to relax and enjoy the build :D and she thinks it can’t be that important. I said it is important because I don’t want to be walking sideways down the path nor do I want a balcony that overhangs on the neighbours side.
So I was up at 6am; couldn’t wait to get out there with the tape. Within 5 minutes I had put a blasted nail straight through my new expensive shorts during a legover operation to set out the string lines again. :cry: 800bt I reluctantly paid for good quality shorts on the wife’s’ say so. Had them 2 weeks! fcuk
Indeed it was the case that they had set the column cages 700 apart instead of 700 to the centres. Anyway the now concreted in cages need to shift by 100mm.
DSC_0261.JPG
the red string line should be the centre of the columns
They would have normally still needed another 250mm concrete but they used it already.
I just wonder if the easiest way is to cut them off at the base and rebend the foot, and then pour in another 250mm concrete.?
After my first few days of trying to lead this operation (read trying not to interfere!) from my elevated watch tower, yesterday the builder for the first time asked the wife what my job was in England. He knew I had drawn the plans, he knows I can set out and he saw me do a quick take off on “dim” paper and remeasure the roof for him when I was querying his roof estimate; I am also sketch detailing most things because I speak no Thai, he speaks no English.
I don’t think he was surprised when the wife told him I did the same job as him, building project manager. What everyone needs eh?
Well I am glad that’s sorted; and hope he can approach me more often for ideas and checking things. After all if he can see I am his on site eyes most of the day and know the job better than he does; then its going to save headaches for him..

My stress level is pretty high now, and when I get stressed diplomacy doesn’t even exist. I need to be assertive. The boss was late to site this morning; he was collecting more rebar but I could see they were preparing for another pour this afternoon. There was what appeared to be another foreman on site this morning, probably borrowed from another job; he looked quite approachable and older than the others so I tried to point out that 2 of the column cages were already set in concrete and 100mm out of position. It was an easy job convincing him that a fat farang (if I ever get fat) would not be able to walk down the side of the house with only a narrow gap and convinced him I would have to walk sideways.
The boss arrived later and the response I get from him at every juncture is “krap” nothing else just “krap” so does he understand does he hell as like. I pointed out the error to him and it seemed he understood.
However he didn’t seem to be doing anything about so an hour later I stepped in again with the string lines and asked that we “check centre duu” I think he actually sees the problem; halley bloody luyah!
Shortly after his foreman was with tape and pencil drawing the correct position on the concrete.
My idea was to cut the legs off and simply re set them and encase in concrete yet again. The foreman wanted to cut and slide the whole frame (exactly my idea!!) but he said my idea was weak apparently. Whats all that about. Does he want credit for the idea or what?
DSC_0257.JPG
more bailing out
DSC_0251.JPG


Another 3m3 connie arrived as expected so I took the opportunity to question the driver about the “steng”. He advised it was 240 strength so pleased about that.
20150530_161154.jpg
concrete pour
DSC_0245.JPG
a bit of an obstruction; only myself to blame for designing too close
DSC_0256.JPG
DSC_0248.JPG


5pm and the wind is getting up; the team have left and confirmed that they would be here again Sunday normally their day off. After a week where I know already have a nickname; its probably “falang check centre” or falang jet cen” after my over zealous re measuring of the column positions. I heard one girl refer to me as check centre so she got a tongue lashing about measuring 5 times as it costs nothing but you make mistake now and every following trade is going to be cursing. Been there done that for the last 30 years.

Well now that the team has left it gives me chance to look at the carnage; but firstly I need to shoot out for half an hour and pay my spa staff salaries.
First thing I noticed, and I blame myself for this, the entrance to my drive was built over the local khlong. From what I see at the neighbours it would likely be a concrete ring drain and backfilled. Well the weight of the connie wagon and left quite a wheel depression in the tamac and concrete outside. I need to remind the builder next time 3 cubes are coming to drop some timber planks at the least. The drive has a nice depression in it also, but I wasn’t expecting 2” of crappy tarmac on 2” of gravel to fair much better.
I checked out the 2 column cages that were aligned incorrectly; quite surprising they were cock on now. :D I see no evidence of damaged concrete so I just wonder if they waited for me to leave site earlier this afternoon and actually gave them an “s” bend kink at the bottom. I will never know because they decided to shutterbox those two first and fill them.
What they have forgotten on this pour is to include the extra two rebars on the sub floor piers. The two incorrect ones had 6 rebars; they generally make a cage of 4 then add extra ones to the lower floors. On this occasion they set up up all the 4 rebar cages but forgot to add the extra pieces in. by the time I spotted it the concrete was still actually green and I could have cut and dropped them in myself but the team had left and taken the cutter with them.
It may sound trivial but that steel is not just to carry the loads, its holding the concrete together to stop it exploding from compression.
No worries; its just another thing for “farang check centre” to complain about in the morning.

I can imagine you lot thinking; what a miserable bugger I am; :twisted: seemingly looking for fault in everything. Its not the case; I am looking for a good to high standard and if that means jumping in and doing some coaching then so be it.
Yes when I was on site in the UK I wouldn’t want the client jumping in; ,he would politely be told to get his arse off the site and make an appointment to discuss and let me get on with my job. Easier said than done I am afraid. If I was watching someone make a cake then yes I know nothing about cakes and would keep schtum until I see and taste the final result. So I will continue to keep an eye on everything and if there is something wrong or out of place then I can nip it in the bud.
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Re: House Extension to "Baan Thai" Chiang Mai

Postby eyecatcher » Mon Jun 08, 2015 12:39 pm

Day 7
Today I decided to give them a break; no not a day off but a break from my supervising; well that is after I have addressed the missing rebar issue. I decided to get my old language books out to remind myself how to tell them that this morning I was going to prepare dim sum for their breakfast.
It’s a difficult moment knowing when best to dive in with the issues to be addressed with my limited language skills. I feel they are now waiting/wondering what I ask of them next.
However it wasn’t too bad; the concrete was already up to 40% strength after the pour yesterday so the best option was simply to get them to give each of the extra rods a 150 bend. It will be encased in the column concrete in any case but at least they have a better bearing than just a cut vertical rod.
DSC_0267.JPG
2 extra rebars they missed

We also have another issue that could have been avoided by checking. We have two new columns almost abutting our existing timber decking posts. The worrying thing is that when they exposed the footing to these posts it appeared there was only about 2 bucketfuls of concrete dropped into a hole the same diameter as the posts; albeit 16”
Part of this footing is now impeding the alignment of the columns. But of course they have realised this morning and are scratching their head about how to move the cages back by 3 inch. They hand bolstered away part of the concrete and then I suggested they cut out just one of the 4 stems and twist the whole lot over. Then add Three more independent rebar legs. Plenty of noises suggesting mine was an idea they hadn’t thought of……..but as usual they went their own way bending and pulling the cage over.
DSC_0270.JPG
alignment problem with existing footing

They are at least making a new shutter to encase and underpin the old footing together with the new footing.
DSC_0277.JPG
Professionally made shutter underpinning existing footing


Another connie delivery; that means another divot and potential collapse of the khlong drain. Today they were completing the final column bases.
DSC_0274.JPG
footing shutters nearly finished
20150531_105803.jpg
another concrete pour
I don’t want to interfere but I had to let them know yet again that I need the ring beams at three different levels so consequently filling up the shutters needs to follow suit.
So seemingly taken heed I saw the girls trowelling out some of the concrete because they had over filled them.
I am dreading tomorrow, I need to be at the Spa; to get a load of ironing sorted, bank visit other errands because our receptionist has a day off. Its looks like they have a lot of ring beam cages to make, backfill the footings; so surely its safe to leave them for a day….!!!!
Dont want to croak my last breath the same way as these fellas
DSC_0265.JPG
Croaked for the final time; noisy buggers
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Re: House Extension to "Baan Thai" Chiang Mai

Postby eyecatcher » Mon Jun 08, 2015 12:56 pm

Day 8
Like hell it was safe to leave them!!! I was away from the job before they arrived and returned at 5pm to see them packing up. They had set up the majority of the ring beam cages but a quick glance I could see several issues that needed addressing before he goes any further.
Despite my best endeavours to advise that the beams should be at different level from 0.4 above 0.3 above and 0.0 datum level they looked erratic to say the least.
DSC_0284.JPG
cages thrown in at the wrong levels!

I had a 400 high cage set up across the path leading to my staircase and similarly across a back door entrance.
DSC_0287.JPG
a steeplechase to get to the back door steps
As verbal communication is limited I am drawing the details as a guide to what is required.
As expected I could see at least 8 of the footing columns had been broken out further because they had over filled them; do they listen, nah.
DSC_0280.JPG
Piers concreted too high and broken out

The wife had a stressful day on her own; time of the month to boot and now she has to listen to me trying to explain the design of our house and why things need to be addressed first thing in the morning. We expected all this stress, of trying to juggle running the business and controlling the house build and arguments between us were likely.
To anyone else it wouldn’t be an issue because you often just want to see the end job and don’t care how they got there. I have been involved in building properties at the top end of quality and the number of times I said “if it was my house would I accept it?” it became the “standard” for everything from foundation to final clean.
“Ok love lets go out for a pizza and beer and we don’t mention the house again today”
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Re: House Extension to "Baan Thai" Chiang Mai

Postby pipoz » Mon Jun 08, 2015 2:00 pm

eyecatcher wrote:Day 8
Like hell it was safe to leave them!!! I was away from the job before they arrived and returned at 5pm to see them packing up. They had set up the majority of the ring beam cages but a quick glance I could see several issues that needed addressing before he goes any further.
As expected I could see at least 8 of the footing columns had been broken out further because they had over filled them; do they listen, nah.
DSC_0280.JPG

The wife had a stressful day on her own; time of the month to boot and now she has to listen to me trying to explain the design of our house and why things need to be addressed first thing in the morning. We expected all this stress, of trying to juggle running the business and controlling the house build and arguments between us were likely.
To anyone else it wouldn’t be an issue because you often just want to see the end job and don’t care how they got there. I have been involved in building properties at the top end of quality and the number of times I said “if it was my house would I accept it?” it became the “standard” for everything from foundation to final clean.
“Ok love lets go out for a pizza and beer and we don’t mention the house again today”


Hi eyecatcher,

What i am seeing seems pretty normal for Thai Standards and not much different from mine, so I wouldn't stress to much. The best you can do with Thai's when they are building is add some quality advice to them, along with putting some checks and balances in place so they don't make any major mistakes.

In short with the structure, just make sure the put the correct reinforcement and bar sizes in pace, space the ligatures/stirrups correctly, overlap the reinforcement to correct length (I just told them to lap the bars in the ground beams for 70 cm for DB12 bar and 850 mm for DB 16 mm bar), cog the bars the correct length/distance where the beams ground beams change direction over the footings. The Thai standard practice when they cog their reinforcement bars at the ends of the beams, is to just turn them down or up and for a short distance, which is not correct and it does nothing structurally.

Also important that they use bar chairs under the bottom reinforcement and keep those bottom bars off the ground (I used 50-60 mm chairs on underside of my ground beam bottom bars), plus also have them use a spacer/spiral type chair of some sort (40-50 mm) to keep the correct cover on the side of the beam against the form work.

Maybe also buy them a TB 3500 electric vibrator/poker for the concrete placement, if they don't have one and make sure the and cure your slab and wrap your columns (use a roll of plastic glad wrap, its check and effective).

The rest will take care of itself during the structure stage

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Re: House Extension to "Baan Thai" Chiang Mai

Postby eyecatcher » Mon Jun 08, 2015 3:04 pm

pipoz wrote:
eyecatcher wrote:Day 8
Like hell it was safe to leave them!!! I was away from the job before they arrived and returned at 5pm to see them packing up. They had set up the majority of the ring beam cages but a quick glance I could see several issues that needed addressing before he goes any further.
As expected I could see at least 8 of the footing columns had been broken out further because they had over filled them; do they listen, nah.
DSC_0280.JPG

The wife had a stressful day on her own; time of the month to boot and now she has to listen to me trying to explain the design of our house and why things need to be addressed first thing in the morning. We expected all this stress, of trying to juggle running the business and controlling the house build and arguments between us were likely.
To anyone else it wouldn’t be an issue because you often just want to see the end job and don’t care how they got there. I have been involved in building properties at the top end of quality and the number of times I said “if it was my house would I accept it?” it became the “standard” for everything from foundation to final clean.
“Ok love lets go out for a pizza and beer and we don’t mention the house again today”


Hi eyecatcher,

What i am seeing seems pretty normal for Thai Standards and not much different from mine, so I wouldn't stress to much. The best you can do with Thai's when they are building is add some quality advice to them, along with putting some checks and balances in place so they don't make any major mistakes.

In short with the structure, just make sure the put the correct reinforcement and bar sizes in pace, space the ligatures/stirrups correctly, overlap the reinforcement to correct length (I just told them to lap the bars in the ground beams for 70 cm for DB12 bar and 850 mm for DB 16 mm bar), cog the bars the correct length/distance where the beams ground beams change direction over the footings. The Thai standard practice when they cog their reinforcement bars at the ends of the beams, is to just turn them down or up and for a short distance, which is not correct and it does nothing structurally.

Also important that they use bar chairs under the bottom reinforcement and keep those bottom bars off the ground (I used 50-60 mm chairs on underside of my ground beam bottom bars), plus also have them use a spacer/spiral type chair of some sort (40-50 mm) to keep the correct cover on the side of the beam against the form work.

Maybe also buy them a TB 3500 electric vibrator/poker for the concrete placement, if they don't have one and make sure the and cure your slab and wrap your columns (use a roll of plastic glad wrap, its check and effective).

The rest will take care of itself during the structure stage

pipoz


Thanks Pipoz.
Yes I like the idea to throw them a few bits of knowledge; teach them something new that doesn't upset their status quo too much; it beats beating them for ignorance.
And thanks for reminding me about the rebar overlaps; in truth I had long forgotten about rebar overlaps but I always remember mesh overlaps were often 400mm so I stick to that one.
No chairs on site but I improvised(naughty naughty) with some half bricks; certainly better than nothing. The concrete certainly doesnt need a poker!! I read a few posts on here about concrete slump and I am surprised that 100mm slump is even achievable.
The concrete we ordered in the uk was generally 50/70mm slump; quite stiff and you did need a poker to get it flowing. Here its self levelling! However if I get my 30kn UK strength then its fine.
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Re: House Extension to "Baan Thai" Chiang Mai

Postby Sometimewoodworker » Mon Jun 08, 2015 3:38 pm

eyecatcher wrote:
No chairs on site but I improvised(naughty naughty) with some half bricks; certainly better than nothing. The concrete certainly doesnt need a poker!! I read a few posts on here about concrete slump and I am surprised that 100mm slump is even achievable.
The concrete we ordered in the uk was generally 50/70mm slump; quite stiff and you did need a poker to get it flowing. Here its self levelling! However if I get my 30kn UK strength then its fine.


You seem to have forgotten that only one of the functions of the "poker" vibrator is to level the concrete. Another, and more important function is to avoid voids specifically beside the form work. There are quite a number of examples of poorly or un-vibrated beams and posts showing significant holes on the surface.

The usual Thai way is to use concrete with so much extra water there that vibrating it would be a very bad idea, but also reducing the strength to that of wet sand.

If you are getting a 100mm slump and not using a poker or hammering the form work you will have voids. DAMHIKT :D
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Re: House Extension to "Baan Thai" Chiang Mai

Postby pipoz » Mon Jun 08, 2015 4:58 pm

Re. Also important that they use bar chairs under the bottom reinforcement and keep those bottom bars off the ground (I used 50-60 mm chairs on underside of my ground beam bottom bars), plus also have them use a spacer/spiral type chair of some sort (40-50 mm) to keep the correct cover on the side of the beam against the form work.

I wouldn't use half bricks as bar chairs certainly not on the bottom beam bars. Brick tend to be porous and will possibly let the moisture from the damp soil travel upwards to the bottom reinforcement bar

Try and get some 50 mm diameter PVC Blue Drainage Pipe, cut it in 60 mm lengths and just notch/file a V in the top, for part of the bar to rest in. The 50 mm blue drainage pipe is the cheapest version of a bar chair or space I have found and they can cut a hundred of them an hour or two

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Re: House Extension to "Baan Thai" Chiang Mai

Postby Roger Ramjet » Mon Jun 08, 2015 5:13 pm

I noticed that you haven't compacted the soil under the beams. Pipoz is right, you must use chairs. I made my own, they are simple to make and take about 30 seconds for each of them.
Your concrete is going to be slop and as you haven't compacted the ground under the beam and are using broken bricks, all the water in it will drain into the soil straight away and it will become brittle and break and won't support anything. It takes 24 hours to cure, but without the water in the curing process you'll end up with crumble.
You need to place plastic under the beams at least and you must cover all the rebar with concrete. As Pipoz said, the bricks are useless as they are porous and you'll end up with concrete cancer within a few months.
Here's how to make the chairs: viewtopic.php?f=3&t=1864&start=360
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Re: House Extension to "Baan Thai" Chiang Mai

Postby pipoz » Mon Jun 08, 2015 5:46 pm

Hi eyecatcher,

If its not to late, I would lift your beam reinforcement up of the ground. You can do this with a few knocked in timber pegs and some reinforcement bar suspended over the top of the cage, then pull it up.

Then remove any loose /soggy material from underneath and slide some black plastic under the bottom bars. Then pull it up the beam side, before you put your outside form work shutter on the beam.

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Re: House Extension to "Baan Thai" Chiang Mai

Postby eyecatcher » Mon Jun 08, 2015 6:15 pm

Day 9
As soon as the builder arrived on site the missus was out there talking to him. I had not slept, walking about at 4am stressing about waste of materials and time and how we can resolve the issues. :(
So I was summoned; we spent a good half hour discussing my concerns. Some of his ideas were certainly different to mine :idea: :?: but convinced us the end result would be the same. :lol: You never really know if the mistakes are mistakes its often “krap” “krap” and “krap” again…….and that’s a word I used several times also, but my meaning was different.

The meeting was quite good and I am happier that he is thinking ahead but when those concrete planks arrive next week I am going to make an educated guess that many will be too long or too short.
He has however started this morning digging trenches deeper as requested, cutting out an unnecessary cage and realigning one one 400mm back, thus making two of his concrete footing piers obsolete. Trenching for another cage that was missed.
The centre piers he wants to construct as 150 square. I had set out for 200 square same as the outer columns. Quite rightly he thinks they will protrude into the room; but I was aware of it and had already decided to accentuate them; but I accepted he could do this and it would be no detriment really…..other than a complete nightmare for them to set them out.

One thing though I was pleasantly surprised at. Beyond the building at the front we wanted just a path, maybe pavings and he wanted to put in a foundation to retain the edge. I was quite happy with a very shallow strip footing on which to set a couple of courses of blockwork laid flat. More than adequate. However he considered that making another below ground beam tied to the existing cages would be the way to go to prevent any differential movement cracks. He also thought in future we may want to build a dwarf wall on it.
DSC_0297.JPG
rebar cages(foreground) for the path

That was an excellent suggestion;(I mean what an excellent freebie…thankyou) he certainly isn’t wanting to skimp on what I thought was a bit overkill; and it doesn’t take long to dig out a small trench and make cages.
DSC_0293.JPG
Unnecessary ring beams for the timber posts


Personally now; I am struggling with stress; I t was a reason I effectively retired at 47 to come and enjoy life….and its back; its my character to be too much of a perfectionist in many things.
The number of times I have said I need to complete the build myself as soon as the roof is tiled; get a couple of helpers and small subby teams for the specialist trades.
How do I communicate effectively with appearing like I carry a big stick.

The team progressed the fabrication of the ground beam cages and the house was already taking shape. The alterations we discussed in the morning had been addressed and another 5 columns had been bolstered out to a lower level.
DSC_0298.JPG
many alterations needed-back door step area
DSC_0294.JPG
cages lowered at back door step area


Very happy with todays progress :wink:
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Re: House Extension to "Baan Thai" Chiang Mai

Postby eyecatcher » Wed Jun 10, 2015 9:42 pm

pipoz wrote:Re. Also important that they use bar chairs under the bottom reinforcement and keep those bottom bars off the ground (I used 50-60 mm chairs on underside of my ground beam bottom bars), plus also have them use a spacer/spiral type chair of some sort (40-50 mm) to keep the correct cover on the side of the beam against the form work.

I wouldn't use half bricks as bar chairs certainly not on the bottom beam bars. Brick tend to be porous and will possibly let the moisture from the damp soil travel upwards to the bottom reinforcement bar

Try and get some 50 mm diameter PVC Blue Drainage Pipe, cut it in 60 mm lengths and just notch/file a V in the top, for part of the bar to rest in. The 50 mm blue drainage pipe is the cheapest version of a bar chair or space I have found and they can cut a hundred of them an hour or two

pipoz


Thanks for the feedback guys. The photos actually were taken on my return home when several things didn't meet my approval. All prior to the shuttering. The cages were all tied to the footing rebar so lifted 50mm or so...........then the half bricks placed under the central points and spoil raked out.
Compacting the underside, yes; agree, this wasnt taken care of beyond a good slapping with the back of the mattock but as with the beams with a 300 void under them, isnt the concrete and the rebar supposed to carry the weight without relying on the soil? :o
Your chair idea Pipoz is excellent. :D I have been used to using plastic chairs cum small steel cradles a la Ramjet in the past and I am going to cut some small pieces for the first floor beams, if thats appropriate?
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Re: House Extension to "Baan Thai" Chiang Mai

Postby eyecatcher » Wed Jun 10, 2015 10:04 pm

Sometimewoodworker wrote:
eyecatcher wrote:
No chairs on site but I improvised(naughty naughty) with some half bricks; certainly better than nothing. The concrete certainly doesnt need a poker!! I read a few posts on here about concrete slump and I am surprised that 100mm slump is even achievable.
The concrete we ordered in the uk was generally 50/70mm slump; quite stiff and you did need a poker to get it flowing. Here its self levelling! However if I get my 30kn UK strength then its fine.


You seem to have forgotten that only one of the functions of the "poker" vibrator is to level the concrete. Another, and more important function is to avoid voids specifically beside the form work. There are quite a number of examples of poorly or un-vibrated beams and posts showing significant holes on the surface.

The usual Thai way is to use concrete with so much extra water there that vibrating it would be a very bad idea, but also reducing the strength to that of wet sand.

If you are getting a 100mm slump and not using a poker or hammering the form work you will have voids. DAMHIKT :D


Thanks STW. I didnt intend to give the impression thats I thought a poker was levelling.....in fact that's the last thing I would have thought of as thats not necessarily critical. I did think (and for 35yr I could have been wrong) that it was for vibrating the concrete between a heavy matted network of reinforcement which would normally not allow the concrete to flow freely.

My tongue in cheek comment in line with yours, refers the fluidity of the concrete that arrives as often as the sun rendering pokers almost obsolete in most domestic builds. I hope I will not have to say "DAM I know that" after tomorrow when I check the result of the concrete pour on those beams. Will report back to you!


Thanks for the comments guys, some useful stuff that could have helped. I am actually about a week ahead of my report in real time, so maybe better for me to catch up to date then I can act on any advice before its too late.
eyecatcher
 
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