Jeremiah Allen

N Lopez wrote:Hi Jeremiah , I am also planning to build a tropical style earthship in Belize and have some of the same questions about passive cooling.  I'm not interested in cooling tubes due to complications and the possibility of snakes or rats getting in there.  Where in the country are you planning to build?  My property is in Cayo outside of San Ignacio.  Please let's connect.

Hey N Lopez.....building near Georgeville....  I ended up abandoning the cooling tubes as the drill was unable to penetrant the quartz rock veins in the hillside.

I did not end up buying the EFBM blocks, I found a builder here who built the home with aircrete and it is performing exceptionally well.  With only a 4in thick aircrete slab for my roof, the corrugated metal roofing (acting as a permeant formwork for the aircrete slab) stays below 80F degrees even after a 100F+ day of sunshine.  Instead of passive cooling, I enlarged the solar system, and purchased high efficiency A/C units to cool the house.  It's working great!  The home is 2500sft and I'm cooling it to 75F with with 54,000BTUs of AC power, it has been cool for more than a month now (24/7) with only about 15KWh of energy spent on normal days, and 25KWH spent on hot (100F+) days.

Chad Kovac wrote:I would advise against using the garage as a cool air battery if you're going to have vehicles in there. Even when not running, cars stink.

Noted....any advice on the questions posted?

I am planning the build of a large (3000sqft+), off-grid, single level, multi-family home in Belize.  The home site is on the west side of a hilltop with excellent steady breezes from the east.  After discovering the earthship concept a few years ago, I became fascinated by the passive cooling aspects of the design, and I want to incorporate cooling tubes which will pass under the peak of the hill and directly into the eastern wall of the home.  The eastern wall will act as a retaining wall, and will be dug into the hill side, which means that most of the prevailing wind will pass over my house.  So by placing the cooling tubes under the peak of the hill, I will not only be able to capture some of that natural breeze, but also cool it before it enters the house.  My question is about the tubes themselves, this is a hot humid climate, what should I be after in regards to:
1) Number of tubes?
2) Diameter of tubes?
3) Material for the tubes?
4) Length of the tubes?
5) Depth of the tubes?

In order to cool a 3000sqft home, I a guessing that I will need quite a bit of capacity, but I also am concerned that it I get a single large tube (say 24" diameter), then there will not be sufficient surface-area inside the tube for proper cooling to occur.  So I'm thinking multiple smaller tubes would be better, but what size & how many is optimal is not easy for me to figure out.  So I'm calling on the experience & wisdom of the permies to help me figure it out, thank you.

The next questions would be, if I can come up with an idea that will have a very high likelihood of success...what do I do about windows in the home?  Do I reduce the amount of windows (increasing the very highly insulated wall area) and rely on the tube(s) for cooling, or do I maximize windows to supplement the cooling tubes?

edit - BTW, winters are of ZERO concern here.  The coldest temps here are mid to high 50s (F) and we can add layers to deal with that....I am ONLY concerned about cooling and potentially dehumidifying the air.

edit 2 - I am building with EFBM...  https://efbm.com/EF-Block-ICF-Blocks.html