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Insulation of Homes in the Philippines

I have written in the past about the heat and also about construction techniques here in the Philippines. As I have mentioned most homes and most buildings are in the “Post and Beam” style of structure. That is concrete posts, or columns supporting concrete beams. This is the framework for the structural part of the building. Then the open area is filled in with 4 inch concrete hollow blocks.

As we know, insulation is based on layers with air gaps. Also concrete absorbs the heat as the heat tries to penetrate the walls.

I have been asked about using insulation in the walls to keep the heat out and the home cooler.

Just like concrete, insulation will slow down the heat from penetration, but as the day progresses, the insulation, like the concrete will absorb the heat. Then as the sun goes down and the off the heat will radiate from the walls.

Also here most roofs are corrugated steel or steel sheets stamped to look like tile. With the sun shining on it all day your attic builds up with heat  and heats the attic.

Soffit vents and ridge vents will help a little. Also if you have low open windows on one side of the house, and open windows on the opposite side of the house up higher, natural convection will cause a breeze or airflow through the house. As heat rises it will pull in air from the lower open windows and hotter air will exit through the higher windows.

Another thing you can do is put a cupola on the high point of the roof. A cupola is a structure like a little doghouse. It can be round, square or octagonal in shape. Then you install vents on the sides. With this the heat in the attic will rise into the cupola and the breeze will blow through the vents and clear the heat out.

An expensive way is always to run air conditioning all day, but most of us come here for a cheaper way of life and do not want to spend all our savings on the electric company.

24 Responses to “Insulation of Homes in the Philippines”

  1. Tom Ramberg says:

    Hi Bruce,

    One of my first projects upon returning home is to add ventilation to the roof of our house. Our roof has plenty of soffit vents but no vents in the upper areas of the roof. I hope to find some of the ugly spinning roof vents like here in the states. I will install them on the back roof to hide them. I also plan to put spacers under the ridge cap so there will be a vent at the highest point. I suspect we will enjoy a ten degree reduction in heat from just these modifications. My wife designed a lovely house before we met but neglected the attic ventilation. I remember walking around the house wondering how the heat escapes. It sure doesn’t come out of the soffit vents. We are also thinking about possibly installing a attic fan that will pull air through the house and exhaust the attic at the same time. I have seen some with thermostatic controls. I am afraid that it might still run continuously even if set at 90 degrees. I’m with you about conserving the electricity. I am even working on generating our own by harnessing the energy of the water in our irrigation canal.

    • Bruce says:

      Tom,
      Use or find a designed Ridge vent. If it is too high with wind you could get water infiltration into the attic.
      If your going to add an attic vent, keep in mind to have the exhaust away from windowed areas. You do not want to suck that heated air back into the home.

  2. HonaFange says:

    Terrific site / Will come back.

  3. Steve Baker says:

    Bruce, You seem to have a great deal of knowledge about homes and building construction. I might have you look at my design for the house I plan to build in Davao.

    • Bruce says:

      Steve,
      I would be happy to look at your plans and if you need assistance getting them to be adjusted, permitted or built, I would be happy to do the work for you.

  4. Benjamin says:

    I have a house up in Skyline and have given up on insulation / ventilation. Looking to eventually selling the place and start from scratch. How about introducing earthen sheltered homes in the PH? Dirt is the best insulation around. Does anyone know of any in the area or possibly any holes in the idea?

    • Bruce says:

      Benjmin,
      My first thoughts are these: For an earthen homes you need to build into a hill. Finding a location where your higher than the road for drainage, getting services and with the unstable land in many places building a strong retaining wall.
      Then I think about all the earth born insects.
      I know Skyline and noticed there is usually a nice breeze up there. If you have good cross ventilation, good roof ventilation, a roof covering besides steel and lots of shade trees it would improve the heat factor.
      Fans help a lot too. Unless your willing to run Air Conditioning, ventilation is your best bet. To lower costs on air conditioning here are solar air conditioners that have a power storage to run it at night.
      If you like, contact me and I will come up with my architect to look for ways to improve your home.

    • Bruce says:

      Jose,
      I knew of solar hot water and even aircon, I did not know of solar attic fan except turbans. An attic fan would defiantly help removing heat from the house.

  5. Al says:

    If the house in question is owned then perhaps a solar chimney could be of use: http://coolexcooling.com/2008/01/25/solar-chimney/

  6. Tony Sciortino says:

    Bruce, Nice to see your site. I was browsing becuase I have the same condition here in Angeles that you have mentioned in your brief. Concrete everything and metal roof. I was thinking i really need attic ventilation and thought the easies way was a spinning turbin dealio.. With the heavy and often sidways rain though I was worried about rain entering through the vent slats. As well I dont see any way to install the vent other then a hole in the roof, then elasto patch. this worries me also. Any hole in the roof and any patch always seems..not permanant. A leak waitin to happen. Any thoughts ?
    What would you suggest.

    Regards,
    Tony

    • Bruce says:

      Tony,
      I agree with your concerns with an attic turban. I have three thoughts but they are more involved.
      1) Add an attic fan with a gravity louver on a gable end of the house. Besides cooling the attic, it will draw air through the house. If you add this, put a gravity louver in a central ceiling area. the fan will pull air through the windows, up to the attic and out the side.

      2) If you have a gable on two opposing sides of the house, add a vent on both sides. If you place one below the 50% height of the attic and one above the 50% height, it will cause natural convection and pull in air from the lower vent and out the upper.

      3) At the highest part of the roof, this highest ridge as a cupola or square doghouse, so to speak with enough roof overhang to protect from the elements and louvered vents on all sides. The heat will rise into the cupola and the breeze will push it out.

      There is also ridge vents.

      Hope this helps.

  7. william says:

    My wife just bought a house in Bagong Silang (Caloocan City North). It has a corrugated tin roof and no ceiling. My first project will be to put in a Solar Powered Attic Fan that I bought at Costco in California ($299). I have already installed one in her mother’s house and it works great! Next, I will put in a ceiling — I have been looking for attic insulation, which is how I found this site.

    • Bruce says:

      William,
      I would suggest, if it is available the type that is applied to the roofing, that was your attic is kept cooler.

  8. mary tricia parreno says:

    I learned a lot from this site and I hope to apply it to our low cost home which is terribly warm. Thanks.

    • Bruce says:

      Mary,

      The best advice is lots of ventilation on all four sides and venting the roof to remove the heat there too.

  9. rick bollmeyer says:

    HI BRUCE, nice blog.

    I AM BUILDING AS WE SPEAK. I THOUGHT A METAL ROOF WAS A LUXURY ITEM WITH A LONG TERM GUARANTEE. IN THE US THEY COME WITH AT LEAST 30 YEARS. IMAGINE MY SURPRISE WHEN MY SUPPLIER SAID ONE YEAR. WHAT GIVES? ADVICE PLEASE! FEEL FREE TO REPLY TO MY EMAIL

  10. Tim Warner says:

    Building a house now in Pililla, Rizal, with design choices dictated largely by the need to keep cool and avoid air conditioning costs: house on stilts, lots of ventilation, insulated steel roof, 1.5m eaves etc. So far though I’ve been unable to find a local manufacturer of passive ridge vents. Any ideas?

    • Bruce says:

      Tim,

      Maybe you get someone to make you dormer vents. Put half at a low point and the others at a high point and you will force natural convection air movement.

      • Tim Warner says:

        I actually have planned for louvers in the gable ends of the roof, and lots of ventilation from floor level through traditional Filipino “ventanillas.” The idea for a ridge vent was just for a bit extra. I agree with you that the louver heights should be differentiated, to force convection. Not sure though how to integrate this idea with the prevailing wind direction, which flips from NE to SW over the course of the year, plus diurnal variation in wind direction from being next to Laguna de Bay. I guess fix it so that night-time breezes, off the lake, reinforce convection within the house.

  11. Hi Bruce

    Me and my filipino wife lives here in Denmark, but we have a low cost house in Davao.
    Theres no insolation what so ever, and am planing to renovate inside.
    Would it be a good idea to put 400 mm insolation in the floor, 300 mm on the ceiling with 2 ventanillas on the roof ? I find the floor very hot, czo of the thin concreed.

    Best regards

    Lars

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