As some of you may know, I live on the Texas Gulf Coast. A few days ago the compressor in my central A/C unit died, leaving us without air conditioning in 98 degree heat and 85% Humidity. Our house is a rather conventional beach house design (though we don't live on the beach) that is elevated 8-12' on pilings with Hardiplank (fiber-cement board) siding and an asphalt shingle roof. At the time of construction I did a great deal of research on proper home design for this extremely hot and humid climate, and distilled it down to 2 primary design considerations:
To address the first consideration, ventilation, I added 9 sets of double french doors that open to a (yet to be fully screened-in....think mosqitos) wrap around deck, and 4 large windows to the existing design. Near the apex of the interior ceiling I added a couple opening clerestory windows on the downwind side to siphon the hot air out of the living space and promote passive ventilation.
For active, or mechanical. ventilation I added a very powerful whole-house fan at the apex of the living space and installed 14 super efficient ceiling fans. The whole house fan exhausts into the attic space and it operates in sync with two attic ventilation fans that in turn exhaust the attic air to the outside on the downwind side of the roof.
Regarding the second consideration of hot and humid climate specific design, low thermal mass, I compromised on my design. We couldn't afford a metal cool-roof at the time so we got stuck with your typical asphalt shingles. And I also let the contractor talk me into installing fiber-cement siding on the exterior for it's fire resistance. So the exterior and roof of my home are composed of materials with a significant thermal mass that is exposed to 100+ degree heat in the summertime. What a mistake this turned out to be.
Despite my climate specific changes, I never entertained the idea that I could live here without air conditioning during the 4-5 month summer. But it wasn't until my air conditioning unit died that I realized just how poorly my design performed during the heat of the summer. Despite installing a radiant barrier in the attic and maximizing the insulation, the thermal mass in the envelope and roof of my home created an internal temperature of 98 degrees in my home, measured at 10 pm, midnight, and 2 am. (We closed the house up at 9 pm and used a window a/c in our bedroom.) At 6 am the internal temperature was 87 degrees. I opened up the house and turned on the whole-house fan and now, 2 hours later, it's 79 degrees inside.
Needless to say I am not pleased with myself for taking the conventional approach and ignoring the exterior thermal mass factor in my home. design. I am hopeful that I can afford to have a metal cool-roof installed in the near future and have already began to build (and plant) trellises to shade the west facing walls of my home. Of course, now that I have to buy a new outside unit for my central A/C, the funding for these projects just took a hit.
But the moral of this story, and the reason I'm sharing it here, is this:
If the two-headed demon of an energy and economic crisis ever comes to be reality, and air conditioning is no longer an option for those living in hot and humid climates, expect massive heat-stroke related deaths and migration out of the south.
Our homes are designed as extensions of our air conditioning units (and social identities) here, and do not take climate into consideration. Suburban homes in the south really are designed to be solar ovens, and I'm afraid many people will be cooked by their homes if a situation of social unrest ever develops.
Thanks for reading....Jeff
Wow! Great commentary and thanks for the personal experience.
I have been considering a whole house fan that exhausts into the attic. I am glad to hear that it was a worthwhile investment, in spite of other issues your facing. I have been using smaller bathroom and a darkroom (we have an old fashioned photo darkroom here) exhaust fan.
I have a concrete shingle roof, which is great in winter, but summer is hot and holds the heat well. We installed thermostat controlled gable fans that help a lot. The best bang for the buck beyond that so far has been using the aluminized reflective barrier insulation, radiant barrier...whatever you want to call it. Second best unconventional efficiency upgrade has been to use protective film on the windows. A search online will show plenty of options to choose from. Some of them are guaranteed to prevent intrusion from people, flying debris etc. for up to 24 hours. That level of physical security, while reducing the influx of radiant heat and UV light. I have found that the use of that item, as a test in one room dropped the afternoon temps (direct sunlight) in that room approximately 18 degrees on a +100 degree day. Supposedly the reverse is also true in colder temps, but I have to wait for winter to look at how efficient it is in retaining the heat indoors.
Best of luck with your upgrades and getting the a/c up and running again.
I've always been amazed at how some of the old victorian homes were built. Just about every room had windows facing more than one direction. If the room wasn't on a corner they bumped out the wall a bit in the middle with two 45 degree walls so they could have windows that provided a cross flow for ventilation. Also a large number of the bedrooms would have small balconies for sleeping outside on those hot nights.
thats our old farm house, what with 10' ceilings and big willow oak trees we stay pretty comfortable.
At least one plus with the Hardiplank is that you will never have to replace it like you would with wood, vinyl or aluminum.
Air conditioning is not that old of an invention. It is sad to think that we have so quickly designed and built for a device that is so reliant on both mechanical and electrical energy.
People lived in Tx and Arizona long before there were air conditioners or even fans. Maybe we all should be looking back more to see what wisdom we abandoned.
Being from TX as well--I remember my grandparents' home inland (near Austin). It was built in the mid 1800s and big--It had floor to ceiling windows with 12 foot ceilings and a dog trot down the center with rooms opening off on both sides. (Meaning the front entry and a rear entry to a roofed porch on both ends were in line with each other for shaded ventilation--breezes flowed through with the doors open to screens.. We had no air conditioning--just big ceiling fans (I mean --BIG fans). Upstairs the ceilings were a little lower but still tall. And yes, windows on at least two sides for each room. Also very large shade trees in the yard near the house.
I also remember that we took naps in the heat of the afternoon or rested with a book on the porch...and sweated a lot. Activity picked back up again at dusk when it started cooling off and the breezes came up. One reason BBQ is so popular--you cook outside. Another reason for summer kitchens, too.
One important issue to bear in mind--asphalt pavement holds heat. You can easily fry an egg on black pavement (the sidewalk, too--but asphalt is the worst.) Big cities have a lot of black road....I always said Houston would still be a small cow town without AC. 95 degrees and 90 percent humidity at 9:00 pm. Not fun with all that pavement around.
Its getting super hot here right now as high as 96 in LA today. Palm Springs is well over 100 degrees. I can't imagine what we would be like without electricity and no AC. When it was just my wife and I, we were both ok. But now that we have a baby girl, it frightens me to think what I would need to do if the whole city was on a blackout. Kinda puts things into perspective. If you are not prepared, then things can get real UGLY if the SHTF.
Thanks for sharing that. We went through a heat wave on the East Coast last week. I remember checking some of the evening temperatures in the cities just to see the "heat island" effect: 10:30PM 91 in NYC and 94, 94!! in Newark, NJ. I think it was around 80 at the same time where I am.
But this is a main reason why I am moving now even though real estate hasn't hit bottom and to a smaller town with lots of trees and with some elevation. I just can't see how cities with millions of people living on top of each other will be able to keep cool in the summers without AC. And once they do figure it out, where will they want to live? At least those who can afford it if/when that time comes and the rush is on, it's probably where I am going. Better to plan ahead while you can.
Great post. I live in Phoenix, AZ Today it was 112 degrees. When I leave for work at 9 am I turn off the AC. When I got home at 5:30 pm today the inside temperature was only 87 degrees. Ten years ago when I bought this 1600 sq ft house.....I planted 11 trees all within 30 feet of the house on all four sides. My neighbor has one tree in his yard. Trees are a good natural way to shade a house. The one bearable thing about 112 degrees is the very low humidity. I also have 8 expensive ceiling fans in this 1600 sq ft house.The ideal Arizona home is one with 14" thick adobe walls with a white exterior, and a screened in sleeping porch.
Thanks for sharing your story. I do use air conditioning at night to sleep.
Kai Ryssdal talks to author Stan Cox about his new book "Losing our Cool," which talks about the consequences air conditioning has had on the environment and people's health.
Kai Ryssdal: Last week's crazy triple-digit East Coast heatwave is just a memory now. New York is a relatively sane 92 degrees today. Of course, that still has air conditioners pegged at maximum cool, and it's the same in other parts of the country, too. It doesn't have to be a 100 degrees for us to hit the AC to be comfortable. Not all that long ago we all survived just fine without conditioning the air.
In his new book, "Losing Our Cool" author Stan Cox says air conditioning's actually made us worse off. Stan, welcome to the program.
Stan Cox: Good to be with you.
Ryssdal: Do I have it right that you survived Kansas summers with no air conditioning in your house?
Cox: That's right. Our house does have central air conditioning system. We turn it on for one day a year to make sure it's still in good working order.
Ryssdal: Is that a day of celebration and happiness in your house or do you do it reluctantly?
Cox: We usually time it for when people are coming over to dinner or we have out of town visitors.
Ryssdal: This book you have written is very much a proposal that we should just figure out a way to do without it. Or certainly do less of it.
Cox: I knew that if I wrote a book calling for the prohibition of air conditioning I wouldn't get very far with most people. So what I've tried to do instead is paint a picture of what life might be like if we start reducing our dependence on it.
Ryssdal: Give me some sense of the raw number. How much energy do we use to keep ourselves cool and comfortable?
Cox: Well, the number is approaching a half trillion kilowatt hours per year, which doesn't mean a lot unless you think of it as the entire electricity consumption of all 60 nations of the continent of Africa -- almost a billion people per year for everything. We could also compare it to renewable energy -- solar, wind, biomass, geothermal. Those sources could increase five fold and still would not cover our demand for air conditioning in this country.
Ryssdal: Are we doing air conditioning any smarter than we did in the past? I mean, have we taken advantage of technology to at least use less energy per degree of cooling or however it's measured?
Cox: Well, that in fact has been improved significantly compared with the mid-90s. The efficiency of residential air conditioners that are in use has increased 28 percent. But at the same time, the average air conditioned home is using 37 percent more electricity for cooling -- which seems like a paradox, until you think about the fact that houses have gotten much bigger and that a lot of people have switched from say, room air conditioning to central air and are probably keeping their houses cooler.
Ryssdal: You know, if you walk down the street in the summer time in most of Los Angeles, certainly New York City and I'd bet there in Salinas, Kan. where you are and everybody's got their air conditioning on. There are no people out there, right? There's nobody with windows open sitting on the porch anymore. You lose a certain social aspect of this, because of AC, don't you?
Cox: That was one of the chief reasons I wrote the book was the ill ease I felt in going through neighborhoods that I knew had once been very lively places in the summer and then turned into dead zones. You would not see any human life out there, and the only sound would be the compressors and fans on the air conditioners. And I really do believe that what has been called by one author "nature deficit disorder" is a problem that has been facilitated by air conditioning. You can make a dark home entertainment center with cool, still, dry air a lot more appealing than a meadow, say, in summer.
Ryssdal: Stan Cox. His most recent book is called, "Losing Our Cool." Stan, thanks a lot.
Cox: Thank you, Kai.
Thanks everyone for the great replies. The main climate challenge here is not the heat, but the humidity coming off the Gulf of Mexico. It makes for fantastic winters, but sticky, miserable summers. But it also makes the area very green and lush with vegetation, and offers a year-round growing season.
The only way that I know how to deal with humidity (other than A/C or dehumidifiers) is to maximize the airflow through the house. Though if you have any thermal mass inside the house, like concrete or stone tile and walls, the humid air condenses on these cooler surfaces and promotes mold growth.
Regarding the shade trees, unfortunately my house is 40' tall, so planting a typical shade tree has a very long return on investment, lol. However, when we built the house, I planted Japanese Giant Timber Bamboo along the northwest corner and it grew to 30+' in three years. Now, 8 years after planting it is taller than the house. Unfortunately it has an upright growth habit that doesn't provide much shade until the sun gets lower in the sky. But I think vegetation is the best type of shading, so that is why I'm working on building vertical trellises to cover the walls of the home. If I can grow a food crop vine on these trellises, then I can convert some of the suns energy that is heating up my house to providing food for my family, a win-win situation.
I've played with the idea of using a roof sprinkler to cool the asphalt shingles. The process of evaporation can remove tremendous amounts of heat in a short time, but to make the system efficient enough to use on a regular basis, and to minimize staining of the roof, I need to use rainwater. So the rainwater catchment and storage system necessarily needs to be completed first. I was hoping I could power the roof "irrigation" system with a Photovoltaic direct pump, so that the more solar gain my house gets, the more water is pumped to cool the roof.
By far, the most comfortable spot in the house when A/C is not available is underneath the house (its elevated on pilings) with its deep shade and nearly constant breezes. Unfortunately Hurricane Ike a few years back destroyed my ongoing project to screen in (mosquito-proof) this area, so it wasn't really practical to use it during this A/C outage.
The A/C is now fixed so life is good again in JAG-land, but I was reminded that there is a great deal more work to be done around the house to prepare for our uncertain future.
Thanks again for the replies....best, Jeff
Back in the 70's I was doing a lot of renovation work near Albany, NY. I was working on a mansion that overlooked the Hudson River in Troy. Whoever built this place channeled an underground stream through a trough in the basement floor. The basement walls were five courses of brick thick. I happened to be working there during a brutal heat wave with temps in the 90's every day, but the basement was actually chilly all the time. I understand they used it for food storage, particularly meat, back in the day.
My house, not a mansion, was built shortly after the Erie Canal was completed and has a stone basement. It's a bit damp down there, but always cool in the summer. We have four ceiling fans that keep the house livable even during last week's heat wave that Sager wrote of.
I have come to respect the usefulness of basements in regulating home temps. That mass of earth encasing the basements tends to moderate temps throughout the year. I you have an underground spring, all the better.
Link. Sure you could run this through an exchange unit, so long as there were no leaks.
Great post and topic, JAG.
In our case, we have central air but are planning on a no-A/C future, if only because energy will get so expensive! Our South Carolina house is light-colored with a light-colored roof and adequate ventillation. Still, we added many items to our "to do" list regarding cooling.
1. Solar-powered attic fan. Done, and it's making a huge difference in our energy bills - lopped them by 1/3. Fan + install = $730
2. Repair/replace all screen windows. Materials are all purchased and cost less than $40 - just staples, screening, 1/4"round moldings, and nails.
3. Good quality screen doors are in our future, to be added when nice steel-framed security doors go in. These will add about $300 to each door but cheap ones fall apart. (An inexpensive alternative is a screen CURTAIN, where you push it aside to get in and out. That's just a strip of wood and a dowel on either end of a roll of screening cut slightly longer than your door opening. Nail the wood above your door and you're done!)
4. We are adding a covered outdoor area for cooking and dining. It will be a patio at first, then we add a metal roof, then, eventually, screening. With some hammocks that might be a nice place for sleeping. Total cost will be $600 for materials.
5. We've turned the front porch into an outdoor room, and we intend to add some bamboo shades and a shading trellis. Should be cheap!
6. Any new materials (flooring, wallboard, paints, furniture) going into this house have to be mold resistant. So far we've replaced an aged bathroom linoleum floor full of cracks with ceramic tile. All towels, rugs and bed linens are bleachable. And yeah, we're stockpiling bleach.
Any other cool ideas out there? We cannot add shade trees since we need the space to grow veggies, but might add vines - great idea growing foodstuffs on a trellis!
Check the bleach expiration dates. It does not store well.
Everything else sounds like it is going quite well. Good work!
Thanks Jeff. The A/C loss and possible effects on people is not something I've put much though in and I appreciate the new perspective. I've always thought that A/C brings with it costs that most people never realize. I grew up in Pittsburgh without A/C and everyone spent hot afternoons outside. My parents front yard was the favorite gathering place for neighbors because everyone's house was pretty warm inside. Window fans and sleeping outside on the back porch were the rule in the summer months for those of us unlucky enough to have bedrooms on the 2nd floor.
Today, on a hot humid day here in Indiana, all you here in the neighborhood is the hum of A/C units. Without A/C, we spent summers outside and got to know neighbors very well. With A/C, everyone spends summers inside and we don't know the neighbors nearly as well. In addition to the impact on home design, A/C has had an impact on how people relate to one another. In Indiana, we could get by without A/C without too much trouble, but the south could face some real issues if that came to pass.
Safewrite , I love your Ideas and prep here . When I was a kid we swam in the hottest part of the day and used to put the sheets in the freezer until bed time hoping to be asleep before they warmed up ! This year we are putting off running AC as long as we can stand it . Somehow in my mind I am ok with sweat if I worked and earned it ,but just sitting around and sweating drives me nuts . Some of our days have been HOT but the nights are cooling off . If you can get a good nights sleep you can bare the days . It is almost August and the garden is coming on strong .... your outside kitchen is on my wish list .
It is after nine at night and still 86 degrees ... I am going to hit the cool shower .
Great observation on the bleach, Jager. It prompted me to dig a little and found a great solution (pun?) here. Another improvement on my preppin'. Woo hoo!
Greetings from the other side of the world (where it's winter now!)
We too get hot humid summers. 40+ deg C and 90+% humidity occur rarely combined, maybe 5 days a year, but 30+ deg C and 80% humidity is common for five months of the year.
We have no aircon, and no heating either. Because we've used thermal mass cleverly.
I don't believe in lifting houses way up off the ground..... unless you're going to live UNDER them all summer long! Here in Queensland Australia we have an older style of sub-tropical housing called the Queenslander, like this:
My experience with such houses is stinking hot in summer, freezing cold in winter! Why? NO THERMAL MASS......
The modern replacements are just as stupid...... even if totally different.
House on slab construction is best, because the temperature of the Earth hardly varies. Nothing to do with the concrete floor at all. Our place has INTERNAL concrete block walls 8 inches thick, and mold is no problem, ventilation here is excellent, I designed the house that way....
I'm surprised shingles have thermal mass....... but we never use this material here, so I'm guessing. My perception of asphalt is that it's probably black, and THAT would be its worst feature. Any roof darker than white in this sort of climate is a bad idea... unless it's silver and reflective like ours.
The bleach is to kill germs and mold and make whites WHITE. But there's another way to bleach and disinfect things: sunshine. The next thing on my list is a clothesline. A tall post, a couple of pulleys and some clothespins and we're good to go.
What do you insulate your thermal mass walls with?
Some clothesline ideas can be found here:
I am installing the pulley one, but there are other choices.
I don't....90% of them are internal, and insulating them would detract from the work they do, absorb heat and stabilise the inside temperature....
The only walls facing out are very short (12 ft long) and face due E & W thus getting sun for only half the day (less shading from trees) and because they are core filled (solid 8" thick concrete) they never get hot enough in summer to be an issue.
The W wall is insulated to some extent by having a library of books against it.
It works! The temp only goes over 27 deg C for maybe ten days a year, and above 30 for one or two.
Three years ago we had a monster frost, and when it was -6C on the S verandah, it was still 16C inside with NO HEATING!
I swear by thermal mass..... but it must be used in such a way as to be advantageous. Certainly NEVER on the roof!
Wod I had no idea how dependent folks down south were on AC. Here in Maine there's probably only about 3 really sticky hot days that one really want AC, though many folks run it much more than they need, including at my office. I find by just never using it anymore I get acclimated and don't miss it.
One of the funniest things some folks do is take a long hot shower, dump all that energy down the drain, then step out of the bath into their air conditioned house. I just take cold showers in summer.
Building off this topic, all my choices are built on lower expectations for energy now. For example,my push mower and weedwacker both died, so I just got some hand tools instead. Takes longer, but I like the quiet and the excercise.
Sounds like my dream-house Mike! I realize that internal thermal mass (shielded from solar gain) is a great solution for 90 percent of the climates, but the humidity is just too high year-round here. For example, most houses here have a concrete slab floor covered with stone tile that becomes too slick with condensation to walk on if you leave a door open for too long. Unfortunately we built in a costal flood zone (Hurricanes) and must be elevated, so my bermed, high thermal mass dream-house is not practical.
Re the shingles, of course they don't have the thermal mass that concrete does (though some people use concrete shingles here, lol) but they have enough to be a serious design problem. Mine are light brown in color, the lightest shade I could get, but if my plans for a replacement metal cool roof don't materialize, I will be painting them white soon.
Thanks for the input....Jeff
Its the same way down here in Texas, only its heating that we don't really need (at least along the coast, as its a big state). We really only have two months that require us to heat our house, January and February, and if I lived alone I doubt I would heat it for more than the two coldest weeks. Its too bad, because heating (with gas) is a lot more energy efficient process (and economical) than cooling with A/C.
The cold shower idea works great, or an afternoon swim in a shaded pond (or pool). Inversely, the hot tub works great in the winter.
Some of you might appreciate facts and insights contained in this article entitled Air-conditioning: Our Cross to Bear.
The A/C loss and possible effects on people is not something I've put much though in and I appreciate the new perspective. I've always thought that A/C brings with it costs that most people never realize. I grew up in Pittsburgh without A/C and everyone spent hot afternoons outside. My parents front yard was the favorite gathering place for neighbors because everyone's house was pretty warm inside. Window fans and sleeping outside on the back porch were the rule in the summer months for those of us unlucky enough to have bedrooms on the 2nd floor.
I agree with you ... it will be easier to keep warm then get cool . Plus ,you can always put more clothes on . ... Taking more off is often frowned upon . This should make a lot of difference in what priority we put our preps and location .
Ps . The crazy thing is they tear down shade trees to put up houses ! It is often ten degrees cooler in the country in the summer time .
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