Double-Stud Walls in a Hot Climate
Okay so,
I am building in the Philippines and have purchased a half built house. The challenges in that aside I have questions centered around keeping the place cooler.
I come from a hot climate where we build with thick cement block to help keep the heat down from the sun. The blocks are 13 inches thick. I have noticed in the Philippines no such thickness is readily available. They are building with 4 inch block in my area. From experience from another house there we painted the roof white and put some thin 10 mm poly insulation sheeting above the ceiling to help with the heat and it was somewhat successful.
The addition of push out blinds to shade windows and a large overhang between floors will help with shading, and there is a large open space in the center of the floor plan that goes up to the 2nd floor for allowing heat to rise and be vented out. My question is what if a 2nd wall was built next to the first with a space between them that could be vented into and out of the roof space? Would this be efficient enough to justify the additional cost, or would it be better to do it another way? Like most we are not rolling in money, but this is our planned retirement home and we want it to be as cost effective going forward as possible.
I am also looking into solar and wind energy to supplement or stand alone off grid. The power losses are frequent and as we are not on any major road power loss due to typhoons will take much longer than you might think to be returned to our area. Is there a suggested best way to do this?
Regards,
Bruce
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Replies
> would it be better to do it another way?
In almost all cases, the primary way to get walls or roof to block heat transfer is to add insulation.
Bruce,
The dearth of replies is pretty comm0n for questions to do hot climates in countries distant from North America. I think that's because we are both unfamiliar with the local building practices, and the challenges faced by materials we usually use here in other environments.
Jon's general advice makes sense. What the insulation would be, or there It is best placed in or on the wall I don't know. Your plan to create a vented air-space between two uninsulated walls might work well, but I'm basing that on a hunch rather than any evidence I've seen.
Thank you both.
I have had difficulties finding insulation in the area other than 10mm sheeting. Tried to find Styrofoam sheets for the walls and other than ordering from China hit a dead end there as well. Like you Malcolm I am just working off of a hunch really.
I am looking into a Whole House Fan to add to things and perhaps the double walls vented to that space would work best. I am just concerned about moisture as Rainy Season means lots of water! With the forced venting through the space I am guessing that will keep things dry.
I live in Bermuda and am familiar with the building practices here but in Asia things have taken on a whole new education curve. For example unlike here where we can go to a hardware store and buy nuts, bolts, screws, lumber, tools and most everything for a project; there you have to find several specialty stores for one or a few items only! Then there is the electrical specs, one phase 220? Well unless you are where an old American Base was once, then you might have 3 phase.
Thank you both again for the advice. I will keep looking for insulations and studying what I can find specific to that environment.
Bruce,
Good luck going forward!
Do you have meteorological information for your location? Like typical high and low temperature and humidity?
If the outside temperature is always hotter than the desired inside temperature you just want to keep as much heat out as possible with sealing and insulation and use cooling to remove heat. But if it often happens that on the same day the temperature is sometimes above and sometimes below desired inside temperature, then you can exploit strategies to collect and store heat. I've never been to the Philippines but I've been to Bermuda and I think you may find that the difference between them is that Bermuda is more temperate and better suited to passive strategies.