15 baht for thatch? Last I heard, a piece was going for 5-6 baht in the kilo 18 area. There may be different degrees of quality, but the stuff they make in my neighborhood seems to last for a good year to two.

Saw a house the other day with louvres in the gable ends. Lets out plenty of heat there. Operate by old "choke" cable mounted on an aluminium plate on the ceiling just below louvres. Evaporative cooler units useless... just introduce more moisture into an already loaded system. Dump the most heat you can at the source and then de-humidify what's left with heat pump.

I am getting ready to build a small house, 6.0mX8.0m upstairs and 6.0mX10.0m downstairs, in a village northwest of the Ring Road. Lower floor walls would be made of concrete blocks with stucco on them, and 4 aluminum windows 1.2mx1.5m. The upper floor will be made with wood, with 6 wood windows 1.2mX1.0m with 0.30m glass on top of each, typical for this village. To save money, I would be using some wood from a just dismantled house.
I have read this entire thread to learn about how to keep a house cool. Some questions and some thoughts:
Would there be appreciable advantage in using Q-blocks/Superblocks for the wall, at what additional cost?
For the roof, because of my concern about the weight of the CPAC Monier (concrete tiles) on wood framing, I plan to use stylized tin sheets for the roof. By the way, contrary to my expectation, these cost about 60% more than the CPACs, but you save money in installation.
I understand the importance of reducing heat gain through the walls and the windows as they are close to the living space. I think that with insulation between the studs and with wood windows, my upstairs space would have less gain through the walls compared to your house which I would guess is all masonry.
But, I am confused about the advantage of insulating the attic floor that you all write about. Given that hot air rises, the heat gain in the living space from a hot ceiling has to be the radiated heat. How far below that can go? Could it be that the cold air from the airconditioner installed high on the walls picks up heat from the hot air below the ceiling?
To keep the hot air high, I am thinking of eliminating the attic space by having a cathedral (pitched) ceiling on top of 3.0m high walls. This way, I can install large vents at each of the gable ends, and if that passive system proves to be not sufficient to draw the hot air out, I can install a fan at one of the ends. Since the cold air stays low, I wouldn’t worry of that escaping through the vents. I also happen to like cathedral ceilings.
I am still debating whether to install reflecting foils under the tin roof and cover it with wood, if I have the money, or with sheetrock (gypsum boards) for both insulation and aesthetics.
Your comments/advice please.

I agree with you regarding insulating the attic floor.It would contain heat in the room and make your AC work harder.Large vents with fans would be beneficial in the roof space.You could also control the fans with a thermostat set to around 25-28 degrees.One intake fan on the most shaded side(cooler) and one extract out on the other side.You have to keep the air moving.
The heat gain through walls/windows is what determines how hard your AC works and cools and this is individual to every room in every house.Amount of sunlight daily,trees shading walls,houses shading walls etc are all important to the heat gain and perfomance of AC .Also if the cooled room shares an internal wall with a room with no AC,heat gained through this has a bearing on the AC.
For example my bedroom has 2 bathrooms and one bedroom(used as storeage) through its internal walls.none of these has AC.The door into the bedroom is also at the top of a very hot stairwell.Along with outer walls and windows my bedroom takes a long time to cool at night.Every room is individual to its AC`s performance although the size may be the same as a room where the AC cools more quickly.Because of this heat gain in my bedroom I set the AC slightly higher to 26-28 degrees and it cools me fine and the outdoor unit cuts off/on as per normal operation.I dont want to go into finer details but setting it higher lowers the temperature differential between air off and air on.The majority of AC units sense and are controlled on return air (warmest)temperature at the top of the indoor unit.You could be blowing 20 degrees off but with "air-on" sensing(due too heat gain) 28-29 degrees.So set the temperature higher to improve peformance.It works where heat gain is a problem.
I hope this is of use and you understand it .Ive strayed,as i tend to do, from the initial topic a bit but i hope this helps.
cheers Brian

Keeping your house cool without air conditioning is difficult in a hot climate.

The lead article asks about extractor fans so he is willing to use electricity. Of course heat rises so place the extractor fan at the top of landing or centre of a bungalow but also have a duct leading in the right direction away from the house. Down wind!

I could say that to keep your house cool, dont start from here, knock it down and build it in a shaded place.
On top of a hill of course, to catch the cooler wind
Secondly don't have the house pointing south so it gets the sun all day.
Alternatively
Keep your windows open and invite in all the insects the neighbours reject.
Keep the curtains closed on the South and West facing windows
Sun control screens should be dark enough to stop passers by from admiring your great physique during the day but at night with the light on watch out that you are not contravening any laws by walking about nude.
Light bulbs could be the low energy ones.
Kitchen heat should be confined to the kitchen

Me. Oh, I use Air conditioners and a freezer and get the filters changed or cleaned regularly, as this makes them more efficent. Don't let ice build up by having an A/C and fan on at the same time.
Fortunately, in the Udon Thani province we have "Cool 4U" an expat firm who can give advice on keeping your house and beer cool.
Why not check out his ad in the April/June 2009 issue of the Guide and give him a call. Siting of A/C's, extractor fans and generally keeping cool is not as expensive as you think and just as pleasant, if not more than a cold shower and a cup of tea afterwards.
Don't sweat or lose sleep over keeping cool. Call "Cool4U"

"Don't let ice build up by having an A/C and fan at the same time."

If you have ice build up on your A/C evaporator it needs servicing.

One of the main issues I find is here is that because houses are built with single skin brick walls, they absorb the heat all day long, and then during the evening and at least the early part of the night, give that heat off into the room that you are trying to keep cool with AC. So even by extracting the hot air with fans, keeping windows open or using the AC, the walls act like radiators keeping the room hot. All of which of course makes a rather inefficient use of electric etc.

The roof has a reflective liner under the tiles, and the bedroom ceilings seem to have cooled down well by 11.00pm, whereas the external walls are still giving off heat well past midnight.

I have done what I can with shading the outside of the house with trees etc, (though that is limited); also using sun liners on the curtains (which of course only helps on the windows, which are a only a small part/area of the walls exposed to the sun). I have toyed with the idea of using external sun shades, but don't want to make the house look too much like a "shanty", and there would be difficulties in where and how to position them.

The only other thing I can think of would be to construct some form of additional insulating second wall, e.g. create an internal partition type wall with a reflective insulated liner inside, between the single skin brick wall and the room! However that all strikes me as both costly and untidy, and probably not worth the hassle or cost for the end result.

Arjay makes good points too.

If you have been to the Sahara and seen the Troglodyte type houses you will appeciate what cave dwellers build to keep cool.
Building underground certainly is one way of keeping your house cool but I cant help thinking of all those stone wall built houses in England with their very thick walls which kept the heat in during the winter and were so cool in summer. They had roofs thatched with lots of different materials from grass sods to straw.
Cricketers wear whites to reflect the heat so maybe we should have reflecting white coatings on our walls and roofs, instead of brown brick and tiles?

good point about the AC and the fan at the same time.its either one or the other,never both at the same time.it completlet disrupts the AC air-flow and return air to the sensor.
Also i would check in at the local psychiatric hospital for a couple of days before knocking my house down and re-building it on a hill.among thousands of other reasons for not doing this its not cost effective.

I do use my AC and ceiling fan at the same time!

I do so because I programme the AC to stay on for no more than about 1 -2 hours, and then switch off automatically, when we are asleep and the room (and me) have cooled down. I feel I then need the fan to maintain some air movement, after the AC has switched off.

Is it a big problem for the AC to cope with? I set the AC at 27C.

arjay,in that instance(1-2 hours) its fine but prolonged periods of fans disrupting the air-flow would increase compressor run time.Especially ceiling fans which blow the warmest air from the highest point down across the cool air flow.It then also distorts return air and sensible temperature for outdoor unit cycling off-on.Indoor wall mounted units flow down/across and the air returns above this in an elongated circular movement.These are designed to run with intermittent air disruption but not constant disruption.It would increase electric bills in a big way as well as shortening compressor lifetime to run ceiling,wall or floor fan with the AC.ideally let the AC do what its designed to do.As i said though in this instance what you do is good for you and your comfort. sleep well

Thanks for your thoughts Brian.

Upon thinking about it, maybe the best solution would be to use the AC as currently, but not to use the ceiling fan, and instead use a small fan positioned at the bedside, so that it caused minimal interference with the room/AC air circulation patterns.

I bought some paint out of global - can't remember the name of it - anyway it was light blue and I painted the whole of my living room/dining room with this paint because it had cooling qualities - blo0dy too cold for me so i've switched back to magnolia....nice and warm again.

Hi arjay.Sounds good to me.cheers for now,Brian

well now keeping a house cool, I don't bother after a few years living here 24 is cold, 30 is acceptable, the only thing I suffer from is the humidity, heat live with it, it is cheaper to do that than try to cool down a badly constructed house.
There are ways to insulate the house or even a particular room from insulating the ceiling/attic to double skinning the walls, ( touch hard of you have a two storey house though)
Live in a bunglaow heat always rises you know.
having insulated the cieling my house is never more than 34 when it is 40+ outside an acceptable level and with a floor mounted fan where I am sitting ok.
bascially it is up to you, many people come here and have the air-con on all night.....complain about the cost and then sweat all day, WEHY, aclimatise yourself and live with the warmth, that is why you came here in the first place.