keeping house cool

Evidently neither one of you understand the reason or have been in an attic that has done a proper insulation under the roof.

If it is done with foam the insulation will not let heat penetrate inside the attic and then it will cool down as the roof cools at night. I have been in several houses in south Texas that have this done and their electric bills are very low and you can actually go up into the attic during the hottest part of the day and year and relax as it is very nice.

I am not sold on the foam as it seals the house if done in the attic, walls and floor. It puts you in an ice chest of sorts. They say it is fire retardant and not fire proof. I am not sure if not letting your house breath will let moisture build up and cause other problems.

In other words, I am not sure it is stupid, I am just not sold on it but could with a few facts and not opinions.

Just to make the point that there is "insulation" and there is the "reflective foil" which is intended to reflect heat. We have the reflective foil laid immediately under the tiles.

I have thought about putting proper insulation on the floor of the loft, though as the bedrooms and loft do get hot (and the bedrooms also gain heat through the walls!) that could impede or slow down the cooling which would take place at night. So I see that as a bit of a double edged sword.

Each situation is different. You can't make any blanket statements about insulation or not, you have to look at the whole house as a system, each part interacting with the other.

If the attic is properly vented, with a good exhaust fan, preferably hooked up to a thermostat, the question of insulation under the roof becomes almost moot. The fan, if properly sized, should keep the attic temp almost the same as the outside temp. Attic spaces here in Thailand don't seem to be vented, although I've never crawled up there to verify. Can't understand why, as the attic just becomes a big heat sink at the end of the day.

I once restored an old house in Ohio that had an old fashioned attic, you could walk around upright in it. It had batt insulation under the roof and a whole house fan. When the fan wasn't running (when it was hot outside) the attic was somewhat warmer than the rest of the house, but still not uncomfortable. I attributed that to the fact that heat rises and the hot air was collecting in the attic. The fan took care of that quickly.

Still, as has been mentioned before on this thread, the biggest (and cheapest) thing you can do to keep cool is shade, shade and more shade. The in-laws house in Amnat Charoen, about the same temp as Udon, is never uncomfortable, with no air conditioning. The house is surrounded by overhangs, patio covers, trees, etc. the sun rarely touches the walls. By contrast, our house here in Udon, with little shade, gets hotter than the hinges of Hades. I honestly could not live here if we didn't have air conditioning in the bedroom.

banpaeng wrote:Evidently neither one of you understand the reason or have been in an attic that has done a proper insulation under the roof.

If it is done with foam the insulation will not let heat penetrate inside the attic and then it will cool down as the roof cools at night. I have been in several houses in south Texas that have this done and their electric bills are very low and you can actually go up into the attic during the hottest part of the day and year and relax as it is very nice.

I am not sold on the foam as it seals the house if done in the attic, walls and floor. It puts you in an ice chest of sorts. They say it is fire retardant and not fire proof. I am not sure if not letting your house breath will let moisture build up and cause other problems.

In other words, I am not sure it is stupid, I am just not sold on it but could with a few facts and not opinions.

Brian I bought old house back in 1975 with no insulation any were I had foam pumped in to my wall and blown in fiber glass in the attic and to rate insulation it called the R. factor R 11 is 2x4 wall R 19 is 2x6 wall you need a minimum of R 30 in the attic if you have a crawl space under the floor you also need R 30 insulation there also
you can get some info on this old house web site or google it for more information OH and my fuel bills as well as my electric bills went down after I insulated every thing BTW insulating the roof rafters cause them to dry rot and can cause your attic to rain trust me it happened in TEXAS at the super Dome many years a go search it out

Try this little test: Find yourself a variety of soup stands: one with the old style tin roof, one with the thin cement panel roof, one with the grass roof, another with the newer style metal roof without the foam insulation, and the last with the newer style metal roof with the insulation. Which is coolest?

The grass roof! By far. Which is next? The metal roof with the insulation. Which is hottest? The tin roof followed closely by the cement panel roof. The metal roof without the insulation is cooler than the cement panel roofs, but hotter than the metal roofs with the insulation.
Just my unscientific observations from stopping at a wide variety of soup stands around/about town while riding a bike.

If it weren't for the rats that infested the grass roofs, or their tendency to catch fire or decompose after a few years, I'd cover my house with a grass roof in a heartbeat.

I was sat outside the other night and sweat was dripping of me and a remembered an appliance for sale in the U.K. for use in central heated house during the winter. It Is dehumidifier. I they are made to be taken room to room and plug in. it seems to me that one of these would not cool the house but by reducing the humidity in the room it would make life more bearable. do not know if these machines can be got in thailand. There has been references to wall insulation on this thread, i found a small press release from siam cement, they are making an insulated brick, all that was shown was a photo , the brick is a sandwich of cement and foam in the middle. no price, no size or insulation properties.

Nimit Services Ltd (Air Conditioners), 4/10-12 Surakan Rd. 042-221-724, the owner's name is Saman Sakulkoo. They had dehumifiers a few years ago, don't know about today. One thing to think about: the compressor in a dehumidifier pumps out a fair amount of heat and supposedly use a fair amount of electricity to boot.

In terms of keeping houses cool, it is normally recommended to create external shading where possible, rather than trying to disperse the heat once it has got into the house. That advice applies whether one has a single skin wall or double wall with insulation. Obviously the latter is preferable, but many of us don't have that, unless perhaps we have been able to build the house ourselves from scratch.

External shading can take many forms, and includes trees and shrubs, as well as awnings, canopies etc. However something I have seen more of recently is what I loosely call the "trellis" type external shading. I've seen them on the new Central shopping Plaza in Pattaya, as well as on the new UD Plaza in Udon. The stuff used on UD Plaza appears to be made of fibreboard, e.g. Conwood type. I have also seen aluminum, steel and even wood and PVC used on such shading. Whilst these are on commercial premises, I see no reason why they can't be used, scaled down on domestic units. Indeed I have seen them fitted on condos and houses in several magazines and sales brochures.

I've attached a few photos to indicate what I mean. I see potential in fitting such shading on domestic houses, in smaller sections, on sun facing walls. What I don't know is who makes it and where, or indeed whether it can be bought in ready made sections. Though I would think it quite possible to make up sections oneself.













There is the point that with the recent ambient temperatures of 37C, whatever one does, the house, walls, furniture etc will nevertheless still acquire a similar temperature, whether in the shade or not.

Well four plus years in the house now, shaded on all sides. Walls don't heat up as much as they did.. I think my attic area is my primary problem I thinking of venting it better and installing insulation. So far I haven't found the workman to do it. Talked to the guy I usually use. His idea was to take the entire roof off and then put in the insulation. So I'm still looking

Found the insulation but I need someone who knows how to properly do it.

That may be enough to bring the electric bills down. About three a o'clock it takes to units running to get the place comfortable we have had extreme heat as a norm we only cool one room. But with this heat, if let the heat build in the furniture it just won't catch up.

We called our aircon guy to check the unit he serviced a few months ago something as we do every year. He said he was running three units in house top keep it cool.

If that doesn't work then it's time to insulate the walls and cover it dry wall. Another aspect to consider is how is the seal on the windows and doors.

In the end this is the hottest year I remember.

Hey you guys, has you forgotten all about building houses. I am from Scandinavia with very cold winters and some hot summers. There is no difference in insulation against hot or cold, the best is double walls as used in all buildings in Scandinavia, but the price is high. What I has done in my house here, is using so called "gasbeton" it is a special stone filled with air and very insulating itself. Temp. diff on outside with direct sun and inside without aircon. is aprox. 15c. Next you have to insulate the roof, this is best done when building the house and is done with "silver mats" (they have it in Home Pro and Global Home) against the metal roof and above the cealing. Keep your doors and windows closed or minimal open and you will have a considerable lower temp inside than outside, ex. 39c out and 28c inside. use a top mounted patlom/vent. and you will find it quite comfortable. Also use tinted glass in your windows, and it certainly helps if your house is raised aprox. 1-1.5 m above the surface in order to keep the air to circulate around the house.
I know this by experience also as engineer
Ps. my wife does not like it raised, because it has no status then, but do not listen to her, it works.

I believe you but a bit late for bricks now, that's why I'm thinking about insulation against the brick then dry wall.

"Keep your doors and windows closed"

That's contrary to what most people do here.......but with a single-story house with insulation in the ceilings, it's proven to be the best method of keeping our house cool........at least cooler than the outside.
If you're lucky enough to be building your own house, designing your house to keep the sun off the windows/walls is worth any added expense. If you don't spend it in the initial build, you'll pay for it later in either add-ons or pay for it by putting up with the heat buildup.
Any windows/walls facing 65-100 and 235-280 (plus or minus) on a single-story house are going to bear the brunt of the morning or afternoon heat. There are ways to counter the effect with large roof overhangs or by putting your carport on the western end to help block the sun. Trees trees trees......the more you have, the better the effect.

To keep the house cool is to install a good quality insulation under the roof and a good choice of roofing material. A green environment would be good too.

Had the foil backed insulation in my attic (bungalow). Thick stuff
Has made no difference whatsoever apart from cutting down my signal on my mobile phone.
Another waste of money I fear.

I had an internal plasterboard wall constructed on the inside of our main bedroom front sun facing wall, with 4" insulation between it and the original single skin brick wall. Though the inside of that wall does remain cool, overall it seemed to make little or no difference to the overall room temperature, certainly in the daytime.

However, logic (and my "pride" ) tells me that it must make a difference at night by retaining the cooled air from the AC in the room better through the insulating effect, - it's no longer lost through that wall, nor having to fight the radiated heat from that very warm exterior wall.