OK, here it is, been a little slow with posting lately … partly because of so ‘net issues and partly because … well, hey, I’m retired. This site is a charter member of the WYSIWYG (What You See Is What You Get) club.
Last installment I busted all over the idea of conventional, “R” Value insulation that blocks the conduction and convention of heat. Reader Fred commented on that post and left a link to this site:
http://www.sibonga.com/philippines_insulating_concrete_forms_icf.htm
Feel free to pay a visit and shop around there, I have no relationship with that site/company, but I’ve visited them many times during my time here in the Philippines. They have a wealth of useful information.
But to stay on subject, let’s get back to the real matter at hand. The sun beating down 12 hours a day on the metal roof over our heads here.
The page Fred pointed out is selling a patented system of "what we call “buhos” construction here in the Philippines. Buhos is a Tagalog word that means literally, “To pour something”. In construction terms it typically means a high quality method of construction where forms are constructed and concrete mix is poured into the forms .. a poured concrete house in other words.
More typical construction, especially for single-family structures is to pour a reinforced footing and then build a “hollow block” wall atop the footing. Normally these hollow blocks are a concrete mixture … here in the land near Mt Pinatubo the bocks are very often similar to what old guys like me used to call “cinder blocks” in the USA. Back then they were made from cinders and fly ash from steam locomotives, here in the Philippines they use lahar, or “volcanic ash” for the sand and aggregate components of the concrete.
There is another solution very popular here around metro Manila, a company called Vas Built www.vazbuilt.com who uses factory made reinforced concrete panels and interlocking columns to build wall very quickly and strongly, kind of like stacking up steel reinforced Lego Blocks.
(Note: Their site linked above is working, but sometimes loads slow, please be patient and don’t don’t write me back about that, it’s their issue, not mine, this is the only link I have).
There is no doubt that buhos is in almost every way a superior construction. In larger commercial buildings it is buy far the most common as well. Properly built and reinforced hollow block can essentially be equal to properly built buhos construction, but that is not the purpose of the discussion we are having. We want to know about staying cool, we’ll assume that any of the popular methods, done right, will be strong enough.
The insulated construction forms technique Fred mentioned makes this, to me a bit astounding claim: Insulated; Air-conditioning is seldom necessary.
Let me make an editorial comment about what is ‘essential’ in the Philippines and where people’s idea of ‘essentiality” may differ slightly among people of different backgrounds.
A relation lives in a house that has a central air system … very unusual here in the Philippines. The central air failed to cool one hot day, so he shut it off and left it off for TWO YEARs. Then, and only then, he took the bull by the horns and called in a service tech to find out what it would cost to get the system repaired. 400 Pesos (about $8 or $9 USD) later the aircon was humming away again and cooling fine.
Obviously, air-conditioning was hardly essential to my relative. World you go without for two years, without even knowing the cost to get it fixed? No, don’t think many of you would, but I have the idea that the statement about “air-conditioning seldom being necessary” comes from the same line of thought. I said before and I’ll say it again.
One, you can not effectively insulate a house here by insulating the walls only. If you don’t effectively block the radiant heat from the sun shining on your roof, insulating the sidewalls is locking the barn after the horse is stolen … it’s pouring money down a rat hole.
Two, Unlike the US where the sun frequently bakes south and west facing walls for hours at a time, the sun here is ALWAYs almost vertically above, and the length of day varies less than an hour from summer to winter … so you never have the sun load on exterior walls that is common in the USA. In fact, with the common wide roof overhangs here, it’s easy to keep all but west facing walls in the shade all day long. What works well in, say, Texas, does not work the same way at all when you are less than 12 degrees from the equator .. ever have the sun north of your house in the USA? No, for sure. Here it is north about half the year and south the rest, but never more than 10 or 12 degrees away from the vertical at noon.
Two, I linked you to a US government study that came to the conclusion that heavy, foam-insulated sidewall construction is not only ineffective for cooling insulation (it’s very effective for heating insulation … remember, we are talking reverse sense and logic for most insulating techniques that Americans are familiar with when we talk about techniques of insulation here in the Philippines) , but in climates even as warm as Miami, (overall, we are much warmer here) it is counter-productive, It ADDS to the overall heating costs rather than saving any.
So please, get to the point, Dave. How do we keep that sun from making the attic (and thus our living areas) a daily oven?
Well here’s one way that is tried and true, in the US and likewise here in the Philippines. Buy far the single most important cooling investment you can make first is something to reflect back the sun’s tremendous radiant energy. And one of the most effective ways ever to do this is a mirror. You could build your roof out of mirror tiles … maybe not too practical, but it sure would look kewl .. or burn out your eyes if you looked the wrong way…
Fortunately, there’s a common substance much cheaper, lighter and more durable than mirrored glass, but nearly as effective at stopping radiant heat … “tin foil”.
Of course “tin foil” is a misnomer .. we are talking about aluminum foil, but pound for pound and peso for peso there is nothing out there that can do more to lower attic (under roof) temperatures, and this roof temperatures. Here’s on big supplier that who dealers herein the Philippines … you can learn a lot from their site. I recommend you do a bit of reading there.
Remember, going back to our earlier conversation about “R” value … this stuff will have virtually no “R” value … but a sheet of thin aluminum between those two calibrated plates and there will be almost no resistance “R) to heat transfer … we are not trying to block conduction … that’s the reason.
Now, after thinking through and hopefully using some foil insulation to block as much of the sun’s radiant energy as we can. what about an additional barrier … one you can apply with a paint brush and one that will even stop some roof leaks as you use it?
Go read about this space age coating. And again, as with the last recommendation, spend some time reading their explanation and background materi
als. It’s way more than just a sales site.
I do not yet know of anyone who handles it in the Philippines, but I may have to change that situation .. because my son and I used a product like this on a metal house trailer roof in Colorado and it was very effective … I can’t believe it is not popular (yet) in the Philippines, but it works and it reflects back and blocks a significant portion of the suns radiant energy … and since the majority of roofs here are painted steel sheet of some form or another, it’s eminently practical to use.
So in this three part series we have learned that:
All the materials that are used in the construction of your home or business absorb and transfer Heat. 80% – 95 % of this heat is transferred, from the warmer side to the cooler side by one or more of the following ways.
1. * CONDUCTION:
Conduction is direct heat flow through matter (molecular motion). An example of conduction, if you lay one end of a butter knife on the burner of your stove, the heat travels by conduction through the metal to the other end that you are holding and it soon becomes too hot to hold. Heat is always conducted from warm to cold never from cold to warm.2.* CONVECTION is the transport of heat within a gas or liquid.
Example-hold your hand above the stove burner and you soon feel the heat being emitted and transferred thru the air upward.3.* RADIATION is the transmission of electromagnetic rays through space. We experience infrared radiation every day. The heat that we feel from sunlight, a fire, a radiator or a warm sidewalk is infrared. Although our eyes cannot see it, the nerves in our skin can feel it as heat.
Now that you understand how heat is transferred,
How do we stop this transfer?Up till now, we have used (mass) insulation such as Fiberglass, Cellulose, Styrofoam, etc. to slow down and resist ("R value") heat transfer. These types of insulation materials only work on heat transfer by means of conduction which amounts to between 5 % – 7 % of the total heat transfer into / out of a structure. That leaves 93 % – 95 % of the total heat transfer to be dealt with by your air conditioner.
I’ve suggested some ways … open to user reports and more discussion.
If you want to learn more about solar and other free energy, like the wind, here’s a course/how to do it manual that teaches everything you need to know about doing your own solar energy production in any country … here in the Philippines for sure. It’s not free, but it’s 100% risk free, you be the judge of whether it works for you or not.
Yesterday I saw a news item where the Philippine DOE (Department of Education) had just converted a school near me in Luzon to solar power. My wife pointed the article out to me with the comment of, "OMG, solar is still very expensive to do." Unlike most such articles this one had some facts and figures.
The plant for the school cost half a million Philippine Pesos and was able to produce 1 to 5 kilo Watts per hour (all the power produced is used, because excess is stored in deep cycle batteries and sold back to the grid as needed) So did the DOE get a bad deal or a good deal?
Well my last electric bill shows I am paying 11.692 Pesos per Kilowatt Hour. That means each hour the school solar plant makes electricity worth almost 30 Pesos. (I’ll take the average between the stated low and high outputs). Ten hours a day of useful sun, means the school is netting about 300 Pesos per day from their small, six-panel pilot program. ( very little difference in day length from summer to winter here)… that means the school is netting 120 Pesos per day, or well over 100,000 Pesos per year … I’m knocking off some potential profit to allow from cleaning, maintenance and periodic deep cycle battery replacement.
So they will get the investment back in about 5 years … unless the commercial rates go even higher, which might happen I suppose. Isn’t that something like a 12% per anum rate of return?
How much are you CD’s earning these days? Do you think the DOE made a good investment? Do you still think solar can’t be made to pay?
Learn how to figure your own rate of return before you accept snap judgments about what is too expensive. It looks to me like solar is a pretty decent investment on it’s own here in the Philippines these days. Of course, YMMV, that’s why it’s a 100% satisfaction guaranteed no risk offer.
Popularity: 8% [?]

First of all, what the heck is heat anyway?








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