chilling walls

Hello everyone.

I've had an idea in the back of my head for some time now, and figured I may as well share it here and see if anyone else has come up with the same concept.


I'm thinking about how to build house walls that act like a swamp cooler. I wish I knew how to do CAD drawing to come up with some pix of the ideas.

Idea #1
Regular wall made out of whatever building material you wish to use, but thin to allow wall cooling effect inside structure. Outside that, corrugated metal running up/down with an opening at the bottom and top to allow cool air in the corrugated areas. On top of that, cedar slats spaced about 1/2" apart to shade the corrugated steel, but allow air movement between the slats. An improvement may be to seal up the top of the corrugated walls into a A frame roof with a large enough air space, and a solar powered exhaust fan to help pull up the cool air from down by the ground threw the corrugated metal sheets.

This should work to keep things cooler on all 4 sides of a box structure.

Then I started thinking about Idea #2.
Same as above, but with water running down the insides of the corrugated channels on some sort of grate to maximize surface area instead of just cool air up. The cedar slats would be replaced with insulation and a finish exterior of some kind with good insulation value. The inside wall would be thin to allow transpiration of the evaporation cooling effect, and lined with a vapor barrier to keep water out. Water could be pumped using a solar pump, and recirculated, or used to top off fish pond, etc.

Has anybody done something like this, and did it work?

Idea #1 was originally thought up for an outbuilding outhouse.

Hi Chris,

Since simplicity really is the ultimate solution, I suggest that you look into hygrothermal mass walls. The effect you are after is achieved through absorption and transpiration of water; water evaporating absorbs heat from the wall's interior, ensuring cool comfort in harsh climates.

All Blessings,
Bill

Thanks Bill.

Researching "hydrothermal mass walls" should keep me busy for a while.

Hi Chris,

I would only add and expand on Bill's advice...and look into a "mass wall" system that "may have" a hydronic system as part of its design matrix.

"Cooling" in general is vastly different than "heating" a structure beyond the ambient mean levels desired. Inevitably cooling leads to condensation, and condensation is water vapor turned liquid...and liquid water is the catalyst for dissolution by both chemical and biological deliquescence activity (rot)...The later is what is the real challenge...

I have designed/built "living walls" (a.k.a. vertical gardens), evaporation coolers (desert coolers) and other "cooling elements" within architecture. These are wonderful things and also very tricky to get correct and in good (long term) working order. Spanish moss is a wonderful medium for the cooling beds/filters of desert coolers, they are also organic and need good tending as this is also a breeding ground for all manner of wee beasty both micro and macro. Similar systems are plagued with the same issues.

The simplest, and perhaps most effective long term cooling element one could place in architecture is a very large (I'm talking tonnage here) thermal mass of stone, tile, clay/cobb, or other related "inert" mass that is little affected by condensate, within the center of a structure. Within this mass could also be a chimney, as well as a "chimney effect" design for the structure itself. Even without hydronics, a mass like this (like we find in the larger RMH) can have a huge effect as both a "heat sink" and a "cooling sink" to stabilize temperature swings within a structure.

For me, and the direction I see good "natural building" is not anywhere near the focus many have on "passive solar." I see few of these designs that work well (or will over generations) like many of the vernacular forms do. Some do function, some even do this well it seems, yet these are the minority of them...not the majority. The majority seem to commonly miss the intended mark for form and function.

As such, depending on the local biome I see good designs that usually follows a vernacular style for a given region. These structures usually have a balance between "high mass" wall systems and/or high volume "thermal resistant" materials (i.e. lofting insulations.) The styles with the greatest level of cross over from desert to cold climates has a "good sweater and jacket" for the outside with there internal pockets filled with "mass." In other words, these structures rely on "loft insulations" in the walls and roof, with a core of mass materials to a balanced level that gives the structure all the heating and cooling needs desired. If exterior walls and roof have lofting insulation forms and the anterior wall are mass in style these homes seem to focus very well in many different biome types. This is why traditional lime/cobb plasters can be found all over the world in both cold and hot humid climates. If folks care to take advantage of the sun for winter heating...build a greenhouse or solarium in proximity to the structure that can be taken advantage of when needed but closed off when not required.

Regards,

j

I once read a story about a young woman who came up with something like this, which she supposedly was patenting and was planning to deploy in Africa.
The walls were thick and worked like a peltier device if I remember correctly.
I did try to search for it again, but I couldn't come up with a search string specific enough to get article to pop up again.