Thread: Most efficient house to keep cool?

After viewing many homes in Isaan I would like any constructive opinions on what design of house keeps coolest and stays coolest.

Many homes are built on stilts and are very traditional for the area. When it is +40C you have the floor exposed to that temperature.

I have found 2 storey homes to heat up the most especially on the upper floor making air conditioning a must for myself. I realize the upper floor gets more breeze but when it is near +40C more breeze just makes it a blast furnace and very uncomfortable.

A single story house built on slab would seem to be most efficient as the temperature of the ground doesn't vary much (with a structure on top of it).
Cheers

Originally Posted by Kurgen

I'm no expert but I reckon using those white thermal building blocks are a much better option than the low grade grey blocks or the little red brick-lets. No doubt double skin walls are a bonus too.

Don't scrimp on your AC either.

Thanks Kurgen - I built one house and used the single row of Q-Con blocks and was pretty happy with them and their insulation qualities. The positioning of that house was ideal with the smallest exterior wall having southern exposure supplemented with trees and a sala to shade that wall. All rooms have A/C but I used the smallest sizes I could get away with so they worked a bit longer but used less power. Of course the A/C salesmen wanted me to buy units nearly twice as big what I purchased?

Hi Gerry,

I used the QCon blocks but at the time wasn't aware there were multiple sizes. The house walls seem to stay pretty cool tho, good roof insulation is a must, I only have the tinfoil crud they put in, but will add some fibreglass batts soon. I looked at the cost of double glazing but it was pretty expensive, good heavy curtains should serve a similar purpose.

Originally Posted by gerry53

After viewing many homes in Isaan I would like any constructive opinions on what design of house keeps coolest and stays coolest.

One with all the doors and windows left open. I think you're looking into this too much. Look at how the Thais build. They don't sit in the house during the day. They sit under grass roofed raised platforms during the daytime. Only to venture indoors once the sun has gone down.

Just my thought. When having my house constructed I included a basement. Why I can't remember but it turns out to be the coolest room in my house. I initially had problems in the rain season with ground water seepage. I sorted that out by digging an adjacent sump tank and piping away the excess water.
If I was to build again, which I won't, then I'd consider a house underground.

This thread may assist the OP? https://teakdoor.com/construction-in-...und-house.html (Half Underground house)

Some fun facts;

The hottest part of Thailand and with a record temperature of 43.8 C is Udon Thani

The coldest place in Thailand is in Isaan also, Loei, with a record temperature of 0.1 C

The Isaan province that receives heaviest rainfalls is Nakhon Phanom.

The Isaan province that receives the lightest rainfall is Nakhon Ratchasima.

^ Buy the buffalo.

Speaking from limited experience, the old shaped teak houses with very high roofs and the sort of flared vents at the side seem a cooler when I've visited them.

An idea I'd also played with is using solar panels to power fans and aircon as well

Originally Posted by SiLeakHunt

Speaking from limited experience, the old shaped teak houses with very high roofs and the sort of flared vents at the side seem a cooler when I've visited them.

An idea I'd also played with is using solar panels to power fans and aircon as well

I agree that the high roofs and ceilings help as the heated air rises. I have soffit and gable ventilation and will put rooftop turbines in if needed but I have above ceiling insulation hoping it will be sufficient.
Solar power for fans is great for air movement but you would need a more complex expensive storage system for A/C and the local electric rates seem cheap enough at this point.

Since you are not interested in "going native," there are ways to minimize the heat affect and you have already mentioned several. Using Q-Con, double walls with an air pocket, roof insulation, tall ceilings, vented roofs all help. You touched on shade, which is huge in Thailand. Large shade trees are a must along with large eaves to shade your house walls will keep things cooler.

Let's face it though, to get through the hot months AC is the best solution. The better your house is insulated, the less your AC will have to run to keep things cool. Humidity is the largest culprit and you can purchase AC units that have additional dehumidifiers even though a regular AC unit will pull moisture out of the air. Just make sure you fit the unit to the size of the area you want cooled.

My house is in Issarn and I run my AC quite a bit. As you have mentioned, the electric bills in Thailand are very reasonable, so why not? If you like to be comfortable, that is the solution. Good insulation with a good AC unit. Shade and a nice breeze is fine most of the year, but if you want to stay cool, AC
is the way to go. Just my opinion.

Thanks Rick - I agree with your opinions and the use of A/C to be comfortable. Plus if you use the techniques you cited to keep the house cool it will take less energy to keep it cool using A/C when it is very hot. When humidity is high it does really drive the heat into the body and your energy disappears.
I still have some trees that haven't grown enough to provide maximum shade but have done most others. I didn't use the double Q-Con rows with an insulating space because I thought the payback wasn't worth it. Due to low exposure to sunlight the single row seem to be working fine.

Gerry, my double row reference was more for when using regular concrete blocks. I had my building crew double wall everything on the outside of the house since I did not feel it necessary for interior walls. The double brick should creat a "dead space" that will retard heat transferance. The reason I took this route was due to the limited knowledge of laying Q-Con by my building crew. If experienced Q-Con workers are available, the use of a single row of thicker Q-Con blocks will achieve a high R factor as well.

I have noticed that when there is direct sunlight on one of my exterior walls, the inside of the same wall is much cooler, so it must be working. Cost of either technique is similar and I like the added thickness for durability reasons. I overbuilt my house, but I wanted it to remain standing for many decades for my young son.

I had a hard time getting my contractor to use Q-Con blocks. They don't seem to want to change techniques but even they found it faster with a straighter wall. Your double wall with an air space will definitely greatly reduce any the heat transfer on the exterior walls.
I had a hard time getting my contractor to think "outside the box" with electrical, plumbing, sidewalk location and finish plus the foundation IMO was way over engineered for a single storey?
Nothing wrong with overbuilding for your off spring!

Originally Posted by SiLeakHunt

I don't own a house in Thailand at the moment, but have been doing a bit of thinking about it.
Does the double skin with airgap run the risk of infestation ?

I'd have thought filling the airgap with foam insulation would be better, or using a thin foil reflective layer on the outside between blockwork and render would help reflect radiated heat.

Infestation from insects, reptiles, rodents or mildew,germs and bacteria?

I guess it would depend if the airspace was open to the outside for drainage or not sealed properly?
If you filled that air space with a foam insulator I would think that would solve the problem. I think buying that type of foam in Thailand would be very expensive as it would be deemed a farang product. In my home country I can pay a contractor to blow in high expansion foam insulation fairly cheaply.

Originally Posted by gerry53

First I am not Thai

Neither am I Gerry but the Thai ways are practicial. I had built an outside area that I too can sit out the hot part of the day if I so wish. Cooler than being in the house and it catches the breeze. It also acts as a play area for my kids, come rain come shine. It measures 10 x 8 m and is always in the shade.

Originally Posted by SiLeakHunt

either that or build Blofeld's layer

layer or lair?

I do apologies, edit done