Windows & Walls

[gdhm]

I am having a large house built in Khon Kaen by my wife's Uncle who is a builder for many years.

He is happy to take my lead on things like size and style of windows and doors and with wall material subject to me not escalating his costs above the agreed pricing.

To date when asking for a price I have only told the builder that for the basic building structure of the house I expect no cutting of corners, satisfactory/quality material to be used and that he's not to even try using any asbestos (or possible asbestos based) materials or other known detrimental to health materials.

My concern is too much heat in the house when built, and how to stop it without excessive use of air conditioning or cutting down light inside by heavily reducing window and glass sliding doors.

I am trying to strike a balance which includes aesthetics as well.

For instance, when I lived in the UK only one bedroom wall had windows (admittedly along much of the wall). The plan I have modelled our house on assumes windows on 2 walls and for the "house length" lounge (for me) ridiculous levels of windows on 3 sides (back, all down the side and front with little brickwork in between).

I could make the back of the house nearly windowless but then aesthetics would not be very good (but it is the back of the house).

I am very aware that Thailand does not seem to go in for double glazing (which astonishes me in such a hot country). I suppose people are mostly too poor and as they cannot afford aircons cooling costs are not an issue..

What I am interested to know if anybody can advise me are on several issues

1) are the typical red small bricks Vs. the larger light-ish breeze block looking blocks (not breeze block I think) similar on prices, strength, suitability for walls and heat insulation. If not, what are the comparative pros and cons.

2) Why do new build houses seem to have so many windows ? Are they cheaper to install than brick walls?

3) Is double glazing viable in Thailand or is it excessively expensive or of poor quality.

4) I have read about tinted single pane windows and glass doors. Are these cost effective at keeping heat out and are the tint coatings durable if a film or, is the tint actually impregnated in the pane itself).

5) Air cons. does anybody have an impression or knowledge on the approx. percentage increase in price with an Inverter model Vs. its cheaper non inverter equivalent. I understand inverters can be up to 30% cheaper to run. Is this also the case if run hard?. I ask this because I may have aircons not actually officially up to the size of the room therefore i suspect they will be running flat out often.

Although the house will be large, I have allowed for the real possibility of 3 direct members of the family exercising their option to move in at some time and will be 4 of us already.

My financial reserves are not good having been stretched buying the wife the land and then paying associated building costs and a new car. I am not in a good position to increase the builders costs much (unless the energy savings pay for themselves in only a few years OR I can used more efficient materials to fight the suns' heating of my house and increase building costs only minimally.

ANY input would be appreciated, especially if based upon experience or knowledge as mine is very limited and at this stage of the building process I may well save myself money and problems later on if I am able to steer the builder in desirable directions on various issues.

Additional info (not sure if relevant at all): The house will be two floors and it is being built around reinforced concrete pylons (looked like 5 metres approx) being driven all the way into the ground and then a metre wide and high area was dug out around each pylon and steel cages placed in the holes and filled in with concrete

The land has been newly raised about .75 of a metre (land fill red clay I think) but the builder and structural engineer tell me that the pylons length in the solid ground will be more than adequate to offset the soft .5metre. Between the many pylons are a network of reinforced concrete bases linking them all together. The external and internal walls will rest on these. They need to be strong as they rest on the .75 metre land fill (soil will be used under the house to fill in the gap between ground floor and these horizontal reinforced bases). Once again the architect and structural engineer are totally happy the foundations are plenty adequate. I believe the original land is red clay (nightmare where I lived in London for heave and subsidence but then houses there were built entirely differently where the walls took the weight and stress of the houses and not reinforced concrete pylons and concrete floors).

Hope I have been clear enough and provided salient information

Many thanks and kind regards to all

Dave

[Razr]

1) are the typical red small bricks Vs. the larger light-ish breeze block looking blocks (not breeze block I think) similar on prices, strength, suitability for walls and heat insulation. If not, what are the comparative pros and cons.

2) Why do new build houses seem to have so many windows ? Are they cheaper to install than brick walls?

3) Is double glazing viable in Thailand or is it excessively expensive or of poor quality.

4) I have read about tinted single pane windows and glass doors. Are these cost effective at keeping heat out and are the tint coatings durable if a film or, is the tint actually impregnated in the pane itself).

5) Air cons. does anybody have an impression or knowledge on the approx. percentage increase in price with an Inverter model Vs. its cheaper non inverter equivalent. I understand inverters can be up to 30% cheaper to run. Is this also the case if run hard?. I ask this because I may have aircons not actually officially up to the size of the room therefore i suspect they will be running flat out often.

1. The Q-Con website has a basic cost/benefit comparison between autoclaved concrete blocks and the traditional thai brick, here: http://www.qcon.co.th/contrast-e.php You might also want to search around the superblock website, which licenses the same autoclaving technology from Hebel.

2. Windows are definitely not cheaper than a traditional Thai brick wall. Newer designs have more windows because light = good IMHO.

3. Double glazing is readily available, but all the stuff I've seen is Chinese sourced (not so cheap, but still nasty), very questionable in quality, or just outrageously expensive. IMHO you're looking for something filled with Argon - anything that relies on silica gel alone is worth avoiding. Here's some links:

http://wrvinyl.com/index.html

http://www.alfab.co.th/windsmith-index_en.php

http://www.windsor.co.th/index.php?lang=en

4. Tinting can be very effective. The thing to remember here is more metal content = better insulation. Don't forget that properly backed curtains can also play a very big role too. In fact, if you're willing to drop the curtains throughout the day to block direct sunlight, properly solar-backed curtains (especially Roman Blinds) can be extremely effective, and will be a hel_l of a lot cheaper than going for double glazing.

5. Inverters chew as much electicity as cyclic air conditioners when run at 100% duty cycle. The key is not to under-spec your aircons, then they won't have to run them "flat-out". Check out the evaporative + inverter aircons Saijo Denki are selling if you really want the absolute most effecient units. Also remember that it's always much better to have 2x 12,000 BTU aircons in a large room than it is to have a single 24,000 BTU unit, if saving on operating costs is your aim.

More notes:

It's a 2 storey house, so downstairs will naturally be cooler anyway. So #1 is to make sure you get the insulation upstairs right - i.e. flashing under the roof tiles (cheap if NOT retrofitted), foil backed gypsum ceiling sheets (cheap too), and perhaps some type of batts as well. Don't buy fiber filled batts though, unless you like rats in your ceiling - the air-bubble foil batts have good effeciency, and rats don't eat them.

As for the pylons, most newer moo ban projects I've been looking at are pounding in 6M long pylons, then building the footings on top of that. This is not something I know much about though, so hopefully someone else can chime in. I'd imagine you'd want to let recently filled land settle for a good few months though?

Edited March 16, 2008 by Razr

[scotsman]

There is many double glazing company"s in thailand who build to german specs the links I have is http://www.pvcwindowsthailand.com/

http://www.europvcwindows.com/

I have had them in my house for over 8 years and they work very well. They have come down in price a lot with more shops opening.

[PadThaiGuy]

I owned a building that was too hot to enter in the afternoons.

After insulating, it was as cool as a wine celler.

[gdhm]

Thanks Razr and Scotsman for the info - VERY helpful .

I owned a building that was too hot to enter in the afternoons.

After insulating, it was as cool as a wine celler.

Well done and congrats

May I ask what insulating did you did to turn things around to such a large extent

Dave

[PadThaiGuy]

It was in the States, wood stud construction with gypsum walls.... Owens Corning Fiberglass in walls, and ceiling, double glaze windows. Ventilated attic. Trees planted to shade the house.

In Thailand, I might build a double brick wall and fill the cavity with fiberglass....at least on the south side.

[PattayaParent]

Filling the cavity doesn't much affect the heat transfer rates as the cavity acts as insulation anyway. Just ensure that it is ventilated.

[Razr]

If using Thai bricks or standard breeze block I can understand why a double brick cavity wall makes sense, as both of these materials store heat. However, take a look at the Hebel autoclaved concrete bricks I've linked to above - with these you get many benefits, including vastly superior insulation properties, with little added expense over a standard single brick wall.

[wpcoe]

Also remember that it's always much better to have 2x 12,000 BTU aircons in a large room than it is to have a single 24,000 BTU unit, if saving on operating costs is your aim.

I've not heard that before. Why is it better? Is it cheaper, more efficient, both, neither?

[Razr]

Also remember that it's always much better to have 2x 12,000 BTU aircons in a large room than it is to have a single 24,000 BTU unit, if saving on operating costs is your aim.

I've not heard that before. Why is it better? Is it cheaper, more efficient, both, neither?

* On not-as-hot days you can fire up a single unit only - even with inverter technology 1x 12000 BTU unit will still chew less than a single 24000 BTU unit.

* When properly placed, you can maximize air flow distribution, making the process of cooling a room much more effecient. I don't have any links handy, but found a couple of sites a while ago that explained the benefit and provided example placements. Google will probably help Two units can effectively double the potential amount of air flowing into the room (quicker cooling), maxmize distribution (less dead/hot spots), and would also mean quieter operation once the target temp is realized as lower fan speeds can be used.

Edited March 17, 2008 by Razr

[Rimmer]

I have built a 600 sq mtr house with 4 air cons. never need to use them though. The place is like a meat locker.

The entire house is built with double Q Con blocks. Absolutly no hot walls anywhere.

My last house had red bricks and cinder blocks which act like a storage heater and release the heat at night. Better to have no walls than use red brick or blocks.

The house has a 60 to 1 mtr crawl space underneath with air blocks on every wall to get a through draft. The floor stays cold.

The sofits overhang maybe 1 meter and draw hot air into the roof space from outside which in turn draws any hot air up into the roof which is then vented via the standard gable end vents. "Air winds" the Thais call them. Failing that fit the self powered galvanized extractors directly on the roof tiles. They work very well indeed.

Single reflective foil under the tiles stop excess direct heat build up in the tiles.

Tinted 6mm glass windows and deep overhangs keep out direct sun.

Pointless exercise to use double glazing in Thailand as the temperature differential is only around 5 degrees.

[JimmyGreaves]

The house has a 60 to 1 mtr crawl space underneath with air blocks on every wall to get a through draft. The floor stays cold.

Does this not encourage problems with animals etc?

[Rimmer]

The house has a 60 to 1 mtr crawl space underneath with air blocks on every wall to get a through draft. The floor stays cold.

Does this not encourage problems with animals etc?

The entire space is blocked in. A single line of maybe 5 or six decorative air bricks on each side backed with steel mesh ensure that nothing gets inside except a worker through a small vented door to check the plumbing. If anyone wants to they they can see the entire project, Q con walls, C pack roof, air winds, windows, crawl space etc. etc. at http://www.flickr.com/photos/banjopicker/

Edited March 17, 2008 by Rimmer

[gdhm]

I have built a 600 sq mtr house with 4 air cons. never need to use them though. The place is like a meat locker.

The entire house is built with double Q Con blocks. Absolutely no hot walls anywhere.

My last house had red bricks and cinder blocks which act like a storage heater and release the heat at night. Better to have no walls than use red brick or blocks.

The house has a 60 to 1 mtr crawl space underneath with air blocks on every wall to get a through draft. The floor stays cold.

The sofits overhang maybe 1 meter and draw hot air into the roof space from outside which in turn draws any hot air up into the roof which is then vented via the standard gable end vents. "Air winds" the Thais call them. Failing that fit the self powered galvanized extractors directly on the roof tiles. They work very well indeed.

Single reflective foil under the tiles stop excess direct heat build up in the tiles.

Tinted 6mm glass windows and deep overhangs keep out direct sun.

Pointless exercise to use double glazing in Thailand as the temperature differential is only around 5 degrees.

Thanks everybody,

I REALLY appreciate all the input and very useful info I am being provided with so far.

These AAC bricks sound really interesting and I am going to speak to my builder about his knowledge and ability to use/lay them and what extra pricing if any for the build quote.

One question please Rimmer.

I note you say you used double Q Con blocks. Does this mean two separate layers of Q con blocks with a gap in the middle. If so does that make a large difference over 1 layer, bearing in mind the heat resistance of Q Con blocks is 6 times less approx. compared to red brick.

I note Q con do a costing on their website based upon 7.5 cms thickness of brick. Is that enough for one external wall layer?. Does anybody know the dimensions normally used when using Thai red bricks? for house exterior walls?

Regards

Dave

[briley]

I am told by Windsor in Chiang Mai that there is only one firm that makes the double glazing units in Thailand - all the rest are imports and fixed sizes.

One added advantage of double glazing is sound proofing.

[Razr]

I note Q con do a costing on their website based upon 7.5 cms thickness of brick. Is that enough for one external wall layer?. Does anybody know the dimensions normally used when using Thai red bricks? for house exterior walls?

The 7.5cm Q-Con/Superblock bricks end up basically the same overall thickness to regular Thai bricks once rendered - i.e. 9.5-10cm. Yes, it's enough for a standard external wall here, as given the way Thai houses are built (with 18cm^2 rebar reinforced posts @ 3-5M spacing) the wall itself is not load-bearing. Even the lintels are spanned between the reinforced posts, the walls are just for fill and for routing plumbing/electrical - which BTW is much easier to do given how easy the autoclaved blocks are to work with.

[Razr]

I am going to speak to my builder about his knowledge and ability to use/lay them and what extra pricing if any for the build quote.

There is a fair chance your builder hasn't actually worked with them yet, as Thai bricks are still very much the "standard" here.

The bottom line should be that the labor charges are much cheaper - the Q-Cons measure in at 60cm (w) x 20cm (H) a piece, weigh practically nothing (you can easily carry one between your thumb and index finger), and only require a super-thin 2mm mortar course vs. the standard 10-20mm the Thais end up using with the red bricks.

The last house I built in Thailand was bricked using Q-Con start-to-finish in < 2 days with 3 (unskilled) workers. I'd expect the same thing would take 1-2 weeks using Thai bricks given the added weight of the product, and substantial difference in mortar and render mixing quantities, and the general difficulties of working with such a sub-par product.

[JimmyGreaves]

I note you say you used double Q Con blocks. Does this mean two separate layers of Q con blocks with a gap in the middle. If so does that make a large difference over 1 layer, bearing in mind the heat resistance of Q Con blocks is 6 times less approx. compared to red brick.

Regards

Dave

Did you do cavity with the blocks and if so did you just leave the cavity empty with ties or no ties and empty?

[gdhm]

I have heard Q con/Superblock bricks are not as easy to work with for fixtures and fittings, due to the need for special plugs to be sued before screwing items to walls.

How true is this, how easy are these special items to get in rural Khon Kaen and how strong/secure are say loaded kitchen cupboards. Is there a danger of the drilled hole just getting bigger as the item is screwed to the wall Or later pulling aways as the plug surround crumbles due to the cupboards pulling on them.

My builder is NOT keen on the Q con idea (I suspect mainly as suggested by Razr that he and many builders in Thailand know little about them) and he does not know how to save money using them.

My concern is that if he does not know how to properly fit, mortar/use the AAC bricks that he may cause problems in the structure of my house that may outweigh my heat/sound resistance gains. I ALSO suspect his mind is closed to less labour costs vs more expensive bricks (does not seem to get the logic -maybe he's paying his builders peanuts anyway ).

Regards

Dave

Edited March 17, 2008 by gdhm

[Razr]

I have heard Q con/Superblock bricks are not as easy to work with for fixtures and fittings, due to the need for special plugs to be sued before screwing items to walls.

How true is this, how easy are these special items to get in rural Khon Kaen and how strong/secure are say loaded kitchen cupboards. Is there a danger of the drilled hole just getting bigger as the item is screwed to the wall Or later pulling aways as the plug surround crumbles due to the cupboards pulling on them.

My builder is NOT keen on the Q con idea (I suspect mainly as suggested by Razr that he and many builders in Thailand know little about them) and he does not know how to save money using them.

My concern is that if he does not know how to properly fit, mortar/use the AAC bricks that he may cause problems in the structure of my house that may outweigh my heat/sound resistance gains. I ALSO suspect his mind is closed to less labour costs vs more expensive bricks (does not seem to get the logic -maybe he's paying his builders peanuts anyway ).

Regards

Dave

No such special fittings or fixtures were required to mount anything in the last house I built using Q-Con. Furthermore, AAC blocks are just soooo much easier to work with when chasing in plumbing and electrical. Sounds like an urban myth/wive's tale to me.

There's apparently a Global House at: 77 Moo 21 , Maliwan Road , Tambon Banped , Amphur Mueang Khon Kaen - Suggest you go see them and get some ideas before doing anything. I think you'll be pleasantly surprised by what you find there, including AAC blocks and the expertise to teach Uncle how to use them.. You might even find a contractor to give you a competitive quote

Less labor costs = less profit = not good for bottom line. Could be an uphill battle if the "force" isn't on your side.

Edit: That he's paying his builders (well, labourers) peanuts is a gimme.

Edited March 17, 2008 by Razr

[jitagon]

I noticed an advertisement in the Classifieds section of this forum for the plans of a house which describes itself as being eco friendly, insofar as no aircon units are installed at all, the cooling of the house being facilitated by planters' shutters and a very high thermatically designed interior space.

[Rimmer]

To answer your question gdhm, My walls are mostly double Q Con with a cavity for cables and such. BUT the two bays at the front are single block and even though they face the sun all day do not get hot on the inside. Somewhere on that web site are pictures of both types of walls being constructed.

Q Con blocks are load bearing, I have seen at least one house built with no sow poons at the corner, just overlapping blocks.

The mortor between blocks is not mortor but glue, hence the very small gap between blocks. It is applied with a small square ladle with jagged teeth.

The question about special plugs is not an issue, ordinary plastic wall plugs are used for pictures. The blocks can be drilled easily and do not require a hammer drill to make a hole.

Like you I used my wife's family of builders to build, they were horrified when I presented them with a Q Con block but after one day they were building straighter walls quicker than they had ever done before and were taking a real pride in their work as never before.

[backflip]

"Why do new build houses seem to have so many windows?"

Windows are more transparent than walls. Windows let in light and, if opened, air. Walls can't do either.

"Are they cheaper to install than brick walls?"

No, brick is cheaper than windows.

[gdhm]

I am going to speak to my builder about his knowledge and ability to use/lay them and what extra pricing if any for the build quote.

There is a fair chance your builder hasn't actually worked with them yet, as Thai bricks are still very much the "standard" here.

The bottom line should be that the labor charges are much cheaper - the Q-Cons measure in at 60cm (w) x 20cm (H) a piece, weigh practically nothing (you can easily carry one between your thumb and index finger), and only require a super-thin 2mm mortar course vs. the standard 10-20mm the Thais end up using with the red bricks.

The last house I built in Thailand was bricked using Q-Con start-to-finish in < 2 days with 3 (unskilled) workers. I'd expect the same thing would take 1-2 weeks using Thai bricks given the added weight of the product, and substantial difference in mortar and render mixing quantities, and the general difficulties of working with such a sub-par product.

If I want all my electrical cables to be in plastic conduit IN the wall (and not run running along the outside what thickness of Q Con block would I need to avoid weakening the blocks after the groves have been cut into them for the conduit.

I ask because if talking of 7.5 cm single layer of Q Con blocks (and many have said rendering can be thinner over Q con blocks) then it seems to me 7.5 cm is too thin if conduits are to be placed in these blocks (BUT I am an ex office worker not a Builder).

My builder who is NOT used to Q Con is wondering about the strength of the blocks anyway, (despite the printed blurb) and certainly if groves are cut into them for the conduit)

Regards

Dave

[Razr]

I am going to speak to my builder about his knowledge and ability to use/lay them and what extra pricing if any for the build quote.

There is a fair chance your builder hasn't actually worked with them yet, as Thai bricks are still very much the "standard" here.

The bottom line should be that the labor charges are much cheaper - the Q-Cons measure in at 60cm (w) x 20cm (H) a piece, weigh practically nothing (you can easily carry one between your thumb and index finger), and only require a super-thin 2mm mortar course vs. the standard 10-20mm the Thais end up using with the red bricks.

The last house I built in Thailand was bricked using Q-Con start-to-finish in < 2 days with 3 (unskilled) workers. I'd expect the same thing would take 1-2 weeks using Thai bricks given the added weight of the product, and substantial difference in mortar and render mixing quantities, and the general difficulties of working with such a sub-par product.

If I want all my electrical cables to be in plastic conduit IN the wall (and not run running along the outside what thickness of Q Con block would I need to avoid weakening the blocks after the groves have been cut into them for the conduit.

I ask because if talking of 7.5 cm single layer of Q Con blocks (and many have said rendering can be thinner over Q con blocks) then it seems to me 7.5 cm is too thin if conduits are to be placed in these blocks (BUT I am an ex office worker not a Builder).

My builder who is NOT used to Q Con is wondering about the strength of the blocks anyway, (despite the printed blurb) and certainly if groves are cut into them for the conduit)

Regards

Dave

There's no problems at all - here's some pics of the last house I built using 7.5cm Q-Con blocks, showing chased-in plumbing and electrical:

Edited March 18, 2008 by Razr

[gdhm]

I am going to speak to my builder about his knowledge and ability to use/lay them and what extra pricing if any for the build quote.

There is a fair chance your builder hasn't actually worked with them yet, as Thai bricks are still very much the "standard" here.

The bottom line should be that the labor charges are much cheaper - the Q-Cons measure in at 60cm (w) x 20cm (H) a piece, weigh practically nothing (you can easily carry one between your thumb and index finger), and only require a super-thin 2mm mortar course vs. the standard 10-20mm the Thais end up using with the red bricks.

The last house I built in Thailand was bricked using Q-Con start-to-finish in < 2 days with 3 (unskilled) workers. I'd expect the same thing would take 1-2 weeks using Thai bricks given the added weight of the product, and substantial difference in mortar and render mixing quantities, and the general difficulties of working with such a sub-par product.

If I want all my electrical cables to be in plastic conduit IN the wall (and not run running along the outside what thickness of Q Con block would I need to avoid weakening the blocks after the groves have been cut into them for the conduit.

I ask because if talking of 7.5 cm single layer of Q Con blocks (and many have said rendering can be thinner over Q con blocks) then it seems to me 7.5 cm is too thin if conduits are to be placed in these blocks (BUT I am an ex office worker not a Builder).

My builder who is NOT used to Q Con is wondering about the strength of the blocks anyway, (despite the printed blurb) and certainly if groves are cut into them for the conduit)

Regards

Dave

There's no problems at all - here's some pics of the last house I built using 7.5cm Q-Con blocks, showing chased-in plumbing and electrical:

Razr ,

You are so kind to answer with photos AND SO FAST TOO.

As they say, a picture is worth a 1000 words and I will certainly be showing them to my Builder tomorrow.

Thank you so much for the time you have spent in your detailed answers to me over the last few days which are extremely helpful.

I wish to also thank the other contributors for their detailed and useful input as well.

With all the wonderful input I have to date I am being greatly helped with direction and my decision making. I am also sure others are being helped by your answers as well.

Terrific!!! I never expected so much assistance and advice or in such a fast time.

Thanks so much everybody .

Dave

Edited March 18, 2008 by gdhm

[Naam]

I note Q con do a costing on their website based upon 7.5 cms thickness of brick. Is that enough for one external wall layer?. Does anybody know the dimensions normally used when using Thai red bricks? for house exterior walls?

The 7.5cm Q-Con/Superblock bricks end up basically the same overall thickness to regular Thai bricks once rendered - i.e. 9.5-10cm. Yes, it's enough for a standard external wall here, as given the way Thai houses are built (with 18cm^2 rebar reinforced posts @ 3-5M spacing) the wall itself is not load-bearing. Even the lintels are spanned between the reinforced posts, the walls are just for fill and for routing plumbing/electrical - which BTW is much easier to do given how easy the autoclaved blocks are to work with.

i too build my house with "Superblock" but not in my wildest dreams i would have used 7.5cm for any outside wall because of the minimised insulation factor. for inside walls they are ok as long as the electrician, plumber or aircon chap use the correct tool to slot the thinner blocks for conduits and piping. if you let the typical village hack a slot with hammer and chisel you end up.... they even managed to hack through 20cm blocks i have used!

in my case the clowns were not instructed in what thickness the special mortar was supposed to be applied and the "normal" 1.5-2cm were used. however the manufacturer told me "no problem!" although the blocks got initially soaked quite a bit.

[Razr]

i too build my house with "Superblock" but not in my wildest dreams i would have used 7.5cm for any outside wall because of the minimised insulation factor.

I have to say that the last house I built (as shown in the pics) stays noticeably cooler when compared to the other houses I've built using Thai bricks - a very noticeable difference indeed. Still, a cool house comes from a number of factors - positioning in relation to sunlight (especially the afternoon sun), ventilation, and then construction materials/insulation of course.

Given my mileage, I'd certainly opt for the (substantially cheaper) 7.5cm AAC blocks again, as I fear the thicker blocks will just fall victim to the law of diminishing returns. YMMV though

[Naam]

I have built a 600 sq mtr house with 4 air cons. never need to use them though. The place is like a meat locker.

you built in Alaska. we are talking of building in Thailand

Pointless exercise to use double glazing in Thailand as the temperature differential is only around 5 degrees.

correct, although the difference is quite often much higher.

[Naam]

i too build my house with "Superblock" but not in my wildest dreams i would have used 7.5cm for any outside wall because of the minimised insulation factor.

I have to say that the last house I built (as shown in the pics) stays noticeably cooler when compared to the other houses I've built using Thai bricks - a very noticeable difference indeed. Still, a cool house comes from a number of factors - positioning in relation to sunlight (especially the afternoon sun), ventilation, and then construction materials/insulation of course.

Given my mileage, I'd certainly opt for the (substantially cheaper) 7.5cm AAC blocks again, as I fear the thicker blocks will just fall victim to the law of diminishing returns. YMMV though

it depends on the individual Razr. i have not come to Thailand to sweat and have my (rather big) house fully airconditioned at all times. not exactly like a meat locker but at comfortable 26-27ºC. as i built a (near identical) house which i designed and built before in a subtropical area i did not have to change the design but had my emphasis on insulation. according to my rough heat load calculations (which i did before starting to build) the additional cost for thicker blocks, roof insulation and forced roof ventilation was approximately 600k Baht which saves me ~4-4,500 Baht monthly on energy cost at present prices = yield of ~7% which i think is quite acceptable.