Building With Q Con Query

[gdhm]

My builder has used Qcon (be it reluctantly at first).

He and other Thai builders tend to have their own views about what is needed and not needed despite what the Qcon manual says.

I wish to ask 2 questions the first is urgent please if anybody knows the answer.

1) All Qcon walls have been made and some rendered already.

The Qcon manual shows after the walls are built but BEFORE rendering strips of mesh wire being placed on the walls where concrete pillars meet with Qcon blocks, and diagonally across corners of window and door frames and over where pipes have been inserted.

My builder (and others) say the mesh is unnecessary and are ignoring installing it.

He thinks the mesh is for added strength and as did not use the flimsy bendable metal tabs between concrete pillars and Qcon joints but used short steel rod inserted by drilling a little in pillars and the QCon blocks. My builder says the mesh is for extra strength but as his steel rods are much stronger than the metal tabs the mesh is not necessary.

My concern is if the mesh is not for strength but some other reason (maybe to do with the rendering BUT to be HONEST I do not understand why the need (if any) for the mess strips.

Can anybody please enlighten me and advise?

2) I have been getting mixed views of raw plugs & screws being inserted into Qcon blocks. Qcon say use heavy duty metal (looks like brass to me) raw plug. Others tell me I can use ordinary plastic plugs (except the real flimsy cheapies).

Which is correct for items such Air cons, extractor fans fittings, shower and water heaters kitchen wooden upper cupboards etc. towel rails and other fixtures to walls

Thank you in anticipation

Dave

[kamalabob2]

Q-Con is the trade name in Thailand for Autoclaved Aerated Concrete Lightweight building blocks. There are at least six other firms making and marketing similar blocks in Thailand. I selected the CPAC version because of the cost in our area. NOT ALL HOME MARTS CHARGE THE SAME PRICE. (same as roof tiles) However you will not regret your decision to build with Q-CON especially if it is at least 10 cm thick for exterior and at least 7.5 cm thick for interior walls.

Did you builder use proper lintels around door openings and above window openings? We did not use any mesh in our home in Buriram province. We did have some sort of tabs installed between the reinforced concrete columns and the CPAC walls. It was not a CPAC product.

I went to the qcon web site and the first thing that "pops up" is a FREE QCON TRAINING CENTER program and the phone number of the training department. My builder had two trainers from CPAC DESIGN come to our building site and use a lap top computer to show a training program and do a question and answer session before any CPAC wall blocks were laid. There was no charge and perhaps Super Block, Q-Con and the other firms offer such a program. All of our "masons" were given written instructions in Thai. I can not guarantee they actually read the booklet but things seem to have worked out fine.

A real WORD OF WARNING. Based on my one house experience, I recommend having ALL your electric conduit, metal outlet and switch boxes installed into the QCON BEFORE any rendering. The same for pipes that will not be covered by Tile. Here is why I stress that. "It NEVER LOOKS AS GOOD if they render first, have conduit or pipes installed and then render a 2nd time". That one time smooth rendering is very nice in my experience, the 2nd time never got quite right. Hence we had all of the air conditioning wires, copper and PVC pipes installed BEFORE rendering. I added some home AV cabling in conduit and it did not look as good after the fact. A minor problem for us since we had most everything laid in cut (insist on a real router as it shows on the instructions, not a all purpose grinder) wall blocks PRIOR to rendering.

They will render DIFFERENT for the interior and exterior walls that will have tile attached. Perhaps you will use a WEBER product OVER the QCON rendering product. Even if they make a wall smooth and suitable for painting, you can switch to tile with no problem.

I'll have to ask how the "raw plugs" issue was handled for water heaters and the air conditioners. No staff ever asked for a special plug and the builder never presented a bill for plugs so it would be safe to say they did not buy heavy duty plugs. Every one of our towel racks went through ceramic tile, which was a larger concern of not breaking the ceramic tiles. We only have one upper cupboard in our kitchen, but the head carpenter supplied his own plugs for all the items he drilled into the wall blocks. He was a big advocate of wood plugs, not plastic plugs. So far I'm happy with his work. He did install three entertainment centers into the wall with bolts and I do not recall special plugs. No TV's have fallen off the wall and the entertainment shelf was mounted into thin 7.5 cm CPAC wall blocks.

I had a good independent air conditioning shop from Buriram send a crew of four men for several days to install the pipes INTO the CPAC wall blocks months Prior to installing several air conditioners. So far none have shifted on the wall.

Looking at my older photos it seems to me the autoclaved aerated concrete blocks only go up to a specified height, then a lintel, and then additional blocks. The initial expense for QCON will be worthwhile in my opinion since you will have a cooler and more quiet home.

Good luck. One final note to those considering Autoclaved Aerated Concrete blocks. Do NOT worry of a few get broken on the truck from Sariburi. Your staff WILL SAW hundreds of the blocks to fit exactly, and NO BLOCKS need to go to waste, even blocks cracked in shipping.

[gdhm]

Hi kamalabob2,

What can I say except WOW!!! and thank you for your wonderful, extensive and detailed reply. It must have taken you a long time and I much appreciate your effort, advice and kindness.

Your House looks great and very large.

Are the lovely and handsome children in your air-con photo yours or the extended family

Mine is sizable too. Much bigger than needed as the 4 or 5 family members expected have since changed plans, (1 new relationship, 1 going abroad, 2 moving out of area and one will be moving in with us. How fast things change. The Builder is a family member so we got an incredible deal another reason for it being large.

I am using 10 cm thick blocks . Qcon price was 31 Baht a block and all supplier except one wanted 31 or 32 baht). My wife tracked down a supplier in Khon Kaen who had a large stock of blocks on site at old prices (still 10,000 blocks) and it was selling at 25 Baht a block - a major saving. I am sure this will not be repeated as I am sure when they restock (we used up 4,200 blocks for inside and out) that they will be charging the new Qcon rates which is going up all the time due to inflation and fast rising fuel and production costs.

My Builder has done as you and has used concrete lintels across the windows and right across the wall. Where a wall s wide between columns he also chose to add smaller secondary vertical pillars and horizontal cross beam even where no windows are. As with you the AAC blocks start again above the lintel's to the ceiling.

Yes my Builder is doing the pipe work first and rendering second. I am quite confident in his ability to re-render when/if necessary as he had to heighten a boundary wall on 3 sides of our property (due to a misunderstanding of the height I required) and he needed to chisel away the old top. Not an easy task I thought, to hide the join but his crew doing the rendering are very good and I cannot see where the join is anywhere on any of the 3 walls.

I know he must do one extra cutting out at least as a he missed a plug outlet on my plans. I am quite confident he will be able to hide it (unless Qcon rendering is not as kind as ordinary for retouching/redoing).

I have shown where air cons would go but my Builder has not not piped for them. So that will have to be done later as well. To be fair he probably did not want to restrict me on positioning in case I moved the beds or lounge around and need the air-cons sited differently from my original plans.

Thanks for the raw plug comments - very helpful. I am not so worried about where there are wall tiles (bathrooms) as the tiles themselves will be quite strong and supportive for anything not too heavy.

Air-cons and kitchen cupboards of course are more important and my main concerns. I have tracked down heavy duty screws at Home Pro in Khon Kaen but not long or thick enough for air-cons. If I can find some I will ask the fitters to use them to be 100% sure the fitting is secure.

I have been told drilling is an important area to be careful and correct first time because Qcon (AAC) block are not as forgiving as Thai Red Clay bricks and can crumble easily around the bit site if drilling is not precise in and/out.

Once again thank you ever so much kamalabob2

Dave

Edited July 7, 2008 by gdhm

[kamalabob2]

Hello Dave,

Some family, some friends in the photo of children by the three air conditioning compressors. Our builder from Buriram did in fact use rounded steel rods for the connections, I am sure for cost and strength considerations. I will say that rendering the CPAC or QCON walls can be so smooth that we had a curtain installer doing a bamboo screen in front of some electrical conduit and BAM he hit conduit which was invisible on his first drill. He is fine, the wall got patched.

We actually had many bedroom furniture fixtures attached to the CPAC wall blocks with no trouble.

We had the air condition shop do all of the air conditioning preparation and actual installation work and it would seem to me that the SIZE and WEIGHT of your inside the room a/c unit will determine what support bolts. I would hope that you will have your a/c condensers HIDDEN from the outside "street view" and will not have wall brackets holding up a 2nd floor unit. Two of the three compressors in the previous photo with 4 children were for rooms UNDER the 2nd floor front balcony. All of the tubing came UP hidden in CPAC wall blocks. One great thing about QCON type blocks is that you can easily have an air condition unit on the INSIDE wall (not a wall that has it's back to the outside wall) so you can get the airflow you want for your bedroom or office. The air conditioning pipes and wires can travel via an inside wall to an outside wall and ultimately to the backside of an outside wall. The key is the air conditioning shop thinking in advance what size copper pipe you will need for the BTU size of split unit you might ultimately install. Buriram Supply did not charge us any extra for bolts to mount the air conditioning units. Coordination with the electrical contractor from Buriram at the same time so that circuits were well thought out as in the architects plans played a role. Plus exactly where the PVC pipe of inside a/c unit "water" drains. In our mater bedroom suite the a/c drain water goes under a bathroom sink counter to the area very near the standard bathroom "dry area" floor drain. We can not see the drain or the PVC pipe unless you open the bathroom cabinet door.

We knew that we would have lower kitchen cabinets. They did NOT render the CPAC wall blocks in all of the lower parts of the kitchen, since they used a WEBER product to attach the tiles which are the raised floor and sides of the built in kitchen counter cabinets. Cheap tile but a smart way to do the inside of kitchen cabinets in my opinion. Certainly not novel in Thailand, but would cost too much in the Western Nations. Our home is perhaps a tad large for the size immediate family we have presently, but I had just finished a minor remodel in California of a house to become a rental property and I made the choice to build larger now and not go through a remodel in Thailand. I think the largest mistake that Ex-pats make when designing a new home in Thailand is too many bedrooms for Thai children. I think they might be just as happy to all sleep in one bedroom to be safe from Ghosts. Even when we have many village relatives spend the night they sleep in only a couple of bedrooms.

Our home is particularly safe since we had an electric fence installed by Wasp Security from Bangkok. We can leave windows open at night with no fear of any intruders since the locals are terrified of the electric fence. I do not regret the the stainless steel fence I installed based on a fencing plan formulated PRIOR to being made aware of Wasp Security through Thai Visa Forum. But the electric fence is far less costly than good stainless steel fencing. NO SALESMEN ever come onto our property anymore since we installed the electric fence. Even the bank insurance sales staff is afraid to interrupt our daily lives now. We can easily turn off the fence during the day if staff is cleaning the stainless steel fence, but no Thai person would "test" to see if the fence is on or off.

[Rimmer]

Mesh screen is placed over joints between block and lintels to prevent cracks forming later. Having said that we did not use it on my present house and only a few small hairline cracks have appeared in a few places. The house is 800 square meters so there would be plenty of opportunity if there was a problem.

No special plugs are required for fixtures and fittings on walls. Ordinary plastic plugs are fine, If you have heavy items then use heavier plugs. Q Con blocks are softer to drill and do not need the hammer function on the drill when making a hole. Care should be taken when breaking through a wall for maybe a pipe as it is easy to knock off a large scab on the inside of the block if they use the hammer function.

It is important to use the correct manufactures screed over the blocks, I have seen mildew form on walls that have had ordinary cement screed applied over Q Con style blocks.

[gdhm]

Mesh screen is placed over joints between block and lintels to prevent cracks forming later. Having said that we did not use it on my present house and only a few small hairline cracks have appeared in a few places. The house is 800 square meters so there would be plenty of opportunity if there was a problem.

No special plugs are required for fixtures and fittings on walls. Ordinary plastic plugs are fine, If you have heavy items then use heavier plugs. Q Con blocks are softer to drill and do not need the hammer function on the drill when making a hole. Care should be taken when breaking through a wall for maybe a pipe as it is easy to knock off a large scab on the inside of the block if they use the hammer function.

It is important to use the correct manufactures screed over the blocks, I have seen mildew form on walls that have had ordinary cement screed applied over Q Con style blocks.

Thanks for this reassurance Rimmer.

Thanks Rimmer, what you say is what I guessed. Real shame I cannot get any Thais on the building site to see (guess) what seems pretty obvious to me. Mostly too late now as the Builder has continued unabated with the rendering (which is Qcon's official rendering plaster). I am relieved to hear you feel it will be of little consequence.

Regards

Dave

[gdhm]

Hi kamalabob2,

Once again thanks for the extensive reply and photos Very helpful.

I can see more clearly form the fence photo how really impressive your house looks.

You have raised some extra questions I would like to ask please.

Electric fence.

I emailed WASP Security without reply.

1) I asked them minimum height and what is the legal position if some thief get electrocuted.

What is the legal position for private residences to have such fencing? Worst case scenario thief

with weak heart dies (heaven forbid). Who is liable?

Who pays any hospital bills if a thief is injured?

I know in the UK the home owner can be liable for harming another, even though climbing over a wall with intent to steal or harm the occupants. I believe the electrified part must be at least 2.4 metres from eh ground or something like that.

2) How much did the whole system and fitting cost you?

3) Am I correct in assuming the main gate is not electrified only the surrounding walls on all sides?

Maybe you know the answers

For my security system

I am seriously looking at the Wisdom alarm system but am concerned that prices are higher than the UK (which is an expensive country) with the PIR detectors (I'd need 8) 87% more expensive (2400 baht compared to 4,500 baht) makes the cost 16,000 baht more than the identical system in the UK. I have asked Maxwell Alarms why their PIRs are so out of line with identical ones bought in the UK, when other items are only 5% to 10% more. I am awaiting a reply - hopefully I will get one. f not I will try to find another supplier of Wisdom Alarms systems in Thailand and get another quote to see if pricing varies.

Air -cons

1) I will not have any Air cons on the front of the house. Two can rest on an upper patio but at present I see no way around 3 being on the upper side walls. The back has very few windows but to run pipes around to the back would cause lengths of pipe to be some 4 metres long and bend around the corner of the house. I don't know how long the coolant pipes can be before inefficiency sets in, but logic suggests to me the longer the copper pipe exposed to the heat and sun the more it will get heated up during the day reducing the cooling effect in the rooms.

2) I had planned to drill the support arms for the outside units into the reinforced concrete base between the lower and upper floors rather than higher up. That will avoid worrying how strong the Qcon fitting will be BUT the problem doing this means the unit will be less shaded from the sun by the overhanging roof.

On the other hand this may not be a major issue as the bedroom air cons will mostly be used at night so efficiency due to heat and sun light will not be very relevant.

Kitchen

Your photos are very helpful.

1) May I ask what sort of price you paid for the grey and black speckled constituted (I believe) marble as that is what we wish to have (alternative very large tiles if very expensive)

2) What sort of shops can I expect to find it?

Sorry for more questions but you answers are not being wasted

Kind Regards

Dave

Edited July 8, 2008 by gdhm