The section at 2:53 - This refers to the angle of the sun ( *NOT the temperature!* ) Apologies if this has caused any confusion. The C was not meant to be there! 😅
I was just about to ask about that, I went back over that section a few times to see if I missed you referencing temperature caused by the sun's angle with the ground
When people talk about "smart buildings", they often mean buildings with lots of sensors , electronics and complicated systems to regulate conditions inside. But truly smart buildings begin with designing a building so it doesn't need all of that or at least most) by placing relative to the sun, providing shae, using materials that absorb or release heat as necessary. In this sense this school is a particularly smart building
The hard part is to figure out hot to make it simple. When you see the design and people say: ahh this is so simple...yeah when you see it working, it is 😂
For those who live in RV campers, they can tell you that adding a shade over the camper makes a massive difference when trying to keep cool. Wondering why this idea isn’t utilized more in the desert southwest of the US and other regions.
I live in the desert southwest near the border with Mexico, and every year in the Spring and Fall we are treated to very heavy wind storms. We often see sustained winds of over 50 mph during the day that go on for many days, and an over-shelter like the one in the video would have to be very strong to withstand the winds here. We do use woven plastic mats stretched between poles like heavy dining flys over outdoor structures like playground sets and carports, but they only last a few years before they need to be replaced. Also, passive solar cooling stopped being a thing here when everyone got electricity. I'm not saying that passive solar cooling wouldn't be a good thing down here, just that it was cheaper to use existing building designs and hardware common in the rest of the U.S. than it was to design unique buildings for this region. Don't forget that price is always an important factor in building construction. It was cheaper to do what was already the standard in other parts of the country, and just run the evaporative cooler during the day to keep things cool. P.S. In the past we made buildings here with thick walls made from adobe, and they were very good at maintaining a liveable temperature inside them, but they also required a lot of upkeep, and the nature of the material limited what you could do with it.
@@whistlingsage9817 wind speed is good at your end so why not you try wind turbine. it will spin all day/night and contineous source of electricity. if your weather is hot only and not humid than evaporative cooling is best n cheap for you.
It's not uncommon for people to have a fully covered porch or an "RV port" over a single wide. Another common thing I see in the desert is a second steel roof to act as a radiant barrier. This is often done as part of roof repairs after the spring winds.
The point with the thick tombe walls is that the heat dispersed at night keeps the rooms pleasantly warm at night instead of too cold due to too quick heat dispersal. This makes optional night time use of these rooms practical as well.
Thank you for that observation! I was wondering why on earth the architect would want to use a heat absorbing material instead of a heat reflecting one for the wall of this building. So, it’s about regulating temperature, not just cooling. That makes it even more interesting.
Im a ventilation expert and business owner bringing natural cooling to the forefront, for people with and without much money. Love this story and yes the Venturi effect, convection abd thermal breaks are the key. Passive is the future.
Frank lloyd Wright houses have been working like this since the 40s and John lautner also. FYI this isn't that new, it's just people actually pay attention to it now
@@trainwreck420ish exactly, its new to many not to history. Same with WHF(whole house fans) 50 year old tech making a huge comeback. People just dont know what it is and i remind them its tried and true NOT new
@trainwreck420ish Do you have any resources that you recommend to learn more about passive heating/cooling? Books, websites, articles, physics concepts, literally anything. I'm going to build my first home on a budget next year, and looking to explore ways for passive heating/cooling. I'm very interested in geothermal.
@nullobject7966 yea, here in TH-cam. There's thousands of hours of architecture and especially mid century modern architecture. I am biased towards frank lloyd Wright and John lautner as mentioned. The two wrote books about organic architecture and the reasons for building such a way. Also Albert Frey and Kendrick Kellogg are awesome as well. There's a quincy Jones Richard neutra and meis van Der Rohr. Try to find mid century modern architecture and stuff built before the widespread adoption of ac. Also Africa has been living for thousands of years without having air conditioning. Also Muslim countries have awesome technology for beating the heat. Towers and domes aren't just for looks.
I once thought of a design here in the US for a mobile home park. Set up a solar panel system on top of the mobile homes that cover the entire roof, and have it raised to allow air flow between the roof and the panels. It would achieve three things. First it would be an entire electric power plant. Second help cool down the trailers. Third protect the roof of the trailers from rain which could over time leak into the trailer. What I didn't think of was an airplane foil.
Mobile homes are the worst type of housing. Why make a carport for a mobile home when you can just build a real home without wheels under it and a design in all of the natural ventilation and insulation? Mobile homes make IKEA furniture look like fine-quality furniture. Nobody should permanently live in temporary housing.
This is a great common sense building. Thank you for presenting it to us. The ram used to make those blocks is an easily dismantled UN design that can be welded together in just about any steel fabrication shop. The basic model is powered by one person. No external power source required. The blocks are moist loam with around 3-5% cement and are air dried for a few weeks before being laid. I've been to a course on this tech and it's fascinating. Look up the CINVA ram for more information.
They should do experiments to see if the can handle long term water saturation, if so you could wet the wall and it would be 10-15% cooler. I've been interested in passive homes since 1967 watching real hippies building a house of mud bricks, just as a interest over the years. I tiled swimming pools in the SW USA, thousands of them, in 122 degree F, near the end I would put up a 40'X20' 70% shade, like a knit nylon, and even had 12+ tiny misters. And only swam-coolers at home. I live past the 45th now and think why people don't build houses alike the arcane Russians with a central huge mass of masonry for the wood-stove/oven. The thinks I think of baking or freezing...
In SE Kansas we have an average summertime high of 93 with humidity. It's hot. But we pay no attention to natural solutions. We could learn from this design. Save a lot of energy.
This roof structure might not stand up to the storms we get in tornado alley. I would love to see thermal mass get more attention though. Earth sheltered buildings are much safer in a tornado as well benefitting from the thermal mass.
@@beth8775 I visited an “Earthship” rammed earth house in New Mexico during August, about a dozen years ago. It was 91 outside and 73 inside, mid afternoon.
Well "...we pay no attention..." because capitalism wouldn't have it any other way. There's 300 million Americans, get one dollar from each of them once and you're wealthy. Get one dollar (or more) profit from each of them every month and you can own a television network and some Senators.
If you want to see these techniques on an architectural scale, visit Taliesin West in Scottsdale Arizona. Frank Lloyd Wright designed his winter home and school with these techniques. He used skills developed by the long past native people in the desert southwest to use on the site. Anytime you are in the Phoenix area, please take a tour. It's very cool.
Fortunately the solution comes in the same package as the problem. The same sun that creates the heat provides also the solar energy to run AC. With today’s technology, cooling is a much smaller problem than heating.
Find the hottest side of your home. If you put up a shade there, you will cool your entire home. It can be a cheap solution, try straw mats, bamboo shades or some kind of cloth. We cool our home with one window unit for our 3 bedroom house. Shades and awnings need to make a comeback.
Thats pretty much the average temperature where I work in Australia (mining, remote areas) and we often use similar building strategies in the outback. The second roof is a common one. We also sometimes add native vegetation to encourage the development of microclimates.
A friend of mind in Washington State has a triple-wide manufactured home. He added a “pole barn” roof 4 feet over his house. It not only provided shade in summer, which sometimes topped 105 degrees, but helped in winter as well with the “snow load”. He did extend the chimney from his fireplace up and through the added roof height to keep smoke from being trapped inter the added roof even though the “pole barn” was open aired on the sides, smoke could still be caught under it on no or low wind days. This was back in 1988……Cheers
Fantastic and heart warming to see great thinking going into solving a local problem. Not looking for awards and accolades - just fixing a local problem and helping locals in a practical, wonderful way. Fantastic! Bravo!
I like the concept. I wonder if that location experiences hurricane force winds. The external roof looks like a wing that could experience major lifting forces in such conditions.
Glen Murcutt has done similar work decades ago in Australia's Northern Territory, where cyclonic wind forces are a major consideration. It's a different climate with different solutions, but it can work. Look it up.
Theoretically the upper roof would be pushed down onto the lower roof because of the low pressure between them caused by the Venturi effect. Now whether that's really true, IDK. They'd have to measure the pressure above and below the upper roof during windy days.
@X4R2 I was thinking the other way around. Higher airflow above the upper roof resulting in low pressure and slower speeds below the upper roof resulting in high pressure. The pressure difference resulting in the air below the roof going from high pressure to low pressure causing lifting of the roof. Like an airplane wing.
As I watched this I was hoping for a temperature for the area which was said but, I wanted an internal temperature from inside the "no A/C needed" building. I think with the smart design, and available materials it's much better than normal building practices. However, I would venture to say it's probably not in the 70 degree range for an air conditioned structure. Very thoughtful!
@@GlueTubber Exactly what I was saying. Is it 30° cooler or 5°. Orientation of a building with respect to sun exposure can do a lot. Trees can produce almost miraculous results. Just wondering about the before and after.
Roughly 20 years ago, Dwell featured a home in the Southern California desert near Joshua Tree called the “Desert Shed.” It featured 3 main features: 1. A concrete slab that was at least double the amount of a normal 1500sq ft home with the house built directly on top of it (to reduce temperature swings from such a massive slab), 2. A metal roof built up over the house for the previously mentioned venturi effect, and 3. The house was south on the slab with its windows facing south to gain solar energy in the winter and take advantage of full shade in the summer.
Thanks for this video. I’ve known before about this project, but your explanation about it, pointing out why one option was better than others, was great.
They study in schools in the heat because they have no other option. Unlike most readers here, I've actually been inside a school on the edge of the Sahara where it was 112F in the shade and no electricity around. The only AC I saw that entire week was in my room in N'Djamena, and in a pharmacy that I had to visit when I got sick. (Pro tip: Don't drink the water. And don't eat the food). And yes, people gathered in hot buildings to do their school and their work ...because there's no other option. But if someone wants to put a swank roof on these buildings and cool them down, heck yeah - let's have more of it!
Dr. Ye Tao uses similar approach to cool roofs in Freetown. Moreover, he ads reflective layer on roof to reflect more sun rays back. Incredible how simple solutions can be so effective. Hope more architects will learn such hacks 👍🌍🕊
95F is a cool day in western Texas to Phoenix AZ. In the southwestern area of the US temperatures can exceed 120°F / 48.9°C, Architect Frank Lloyd Wright designed a few buildings located near Phoenix to be cool in those high temperatures. Also homes in the American in southwest once used construction principles that allowed air to flow which kept them cooler. The Arabian area also built structures that stayed cool during extreme temperatures.
Switch uses this same technique for their data centers here in Las Vegas. A double layer roof, high albedo layer (on top), and they use cooling towers to push cool air between the upper roof and the lower roof.
This is amazing and inspiring! Great strategy for living in hot and extreme climates. Another good strategy is dome roofs. And my favorite strategy of all is building (and growing food) underground, like with earthships, hobbit holes, and the Forestiere Underground Gardens, in Fresno, California. The Underground Gardens are an excellent example and definitely worth checking out! Thank you for this video!
You should also mention that the whole point of the high air speed Venturi is to cause a low pressure zone that will literally suck hot air up through the perforated ceiling.
Saw a few years ago a television programme by the British adventurer / outdoors man Ray Mears. He was in North Africa around the Sahara Desert. He had a Land Rover parked up. He said that he would normally use two parachute fabric covers spaced approximately 30cm apart. He said this kept the temperature down a considerable amout in comparison to a single layer.
The best part about passive designs is you can slap air conditioning on top of them and it'll barely run, but when it really does get that hot where your passive design allows the temperature to rise past 80F, you have the option of turning the AC on. Sure, without the insulation typical in the AC paradigm of an American home the AC will be less efficient, but with all of the passive energy savings you already have, that's okay.
You forgot to mention that the earth bricks also release heat towards the classroom for many hours therefore the perforation of the ceiling so this heat is also released out of the classrom
I mean, this is the real deal. Here we are in America designing houses. I’m building them pretty much the same way with the same heating systems and insulation stuff in the past hundred years. But there’s so much we could be doing to work with nature, and said I
This system works best in arid climes where the humidity is low. With high temperature/high humidity situations, natural cooling is much harder to achieve, though this might be as good as any.
A good number of years ago I did some thermal analysis with SolidWorks Flow Simulation, a tool used for analyzing products like computers and phones, to do some basic probing on the idea of a shade over a roof. What I found was that there needed to be a pretty good size gap, similar to the one shown in this video, to make the concept effective. It is typical of passive flow, density driven flows need a ton of space because the driving force is low. If wind were the primary driver, you could reduce the gap, but then the strategy falls down on a calm sunny day. The holy grail is a passive geothermal heat pipe that uses water as the working fluid. Heating from above, cooling from below is stable though, and can't be used to drive circulation, the driver being changes in density. Ever wonder why the stuff at the top of a cooler can be warmer that the stuff at the bottom? Heating from above, cooling from below, flow shuts down, and with the thermal conductivity of air being so small, the column stratifies thermally. Fun fact, the thermal conductivity of the materials that thermal insulation are made from is actually pretty high compared to the insulation as furnished. The reason is simple, insulation has one job, keep air from moving. The drag induced by insulation nearly eliminates the effects of density driven flow. The Achilles heel, wind loading on the shade is high in storm conditions, so designing it to withstand high winds is probably cost prohibitive. Probably better off designing to be easy to repair than resist crazy wind that only comes around once every 10 years.
I live in areas where temperatures soar upto 48c max and 40c on average. One of problem is low air flow. In desert air flow is good. But biggest problem for us is rainy season with too much humidity. Hot weather lasts for 2 months but humidity weather lasts 6.5 months. Is there any passive cooling method for humidity free homes ?
@@raj66kas Yes an Indian engineer created terracota clay based waster cooling system. But its for hot weather only. when you use water than humidity increases and i need a solution for humidity.
That is challenging. What energy sources are available? Are there streams or rivers to use for hydropower? Is there much firewood? Is there any sunshine during those 6.5 months? Wind power? Reducing humidity typically requires compressor-based air conditioning, or desiccants that need to be dried generally with a heat source.
If you live near the ocean you could pump very deep cold ocean water up and humidity would condense on it. The dew point of the air would be reduced down to the water temperature.
@@mikeguitar9769 Thanks. But i don't live near an ocean or water stream. Only option left for us is compressor based air conditioners. desiccants can be a good starting point for me. I live in Pakistan and pink himalyan salt mine is here. salt mine is also humidity free and has pleasant temperature inside. Thinking about using salt slabs or stones. Place salt in room attach a fan let's see how much humidity it can control. I also found out that there are some salt rooms made for therapies and they have no humidity inside.
I wonder about heat mitigation all the time with my businesses. We rely so heavily on mechanical HVAC solutions in single floor plazas. When an HVAC isnt working correctly the flaws in the structures we have to passively mitigate heat or cool are extremely noticeable. Planting a tree to give shade is a 50 year solution and not practical in a commercial sense. So having a secondary roof is something i def would like to explore
Such an elegant solution! The architect was excellent, and so was the explanation. One other thing about air conditioning, it dumps the heat taken out of the inside of the building to the outside, making areas around the buildings with a/c even hotter. Also given human nature where when a/c is available they often crank it up so it is freezing inside, instead of just comfortable, wasting energy. This was a great video, would have liked to know the temps inside the building when outside is 40 deg.C. How much it can cool?
Give us the statistics: Temperature in the sun, In the shade, and with the Venturi roof. Is it an open roof gap over a ceiling built as an inner roof? Are there vents in the ceiling? One side elevation shows a flat inner roof and curved outer roof, another shows a curved inner roof and curved outer roof. Which is it? Ventilated roofs over ceilings are common in hot countries. In Thailand the gable angle is very steep, about 50°, to allow the hot air to rise. Fans are used to create a breeze. In Thailand often a flat roof becomes an open air top floor over which a gable roof is built for extra shade, This floor is commonly used for clothes drying, which in itself reduces heat required to evaporate water. Bird wire is needed to stop flocks of birds nesting and pooping. The houses are often raised one floor height above a pond of water, or in modern times, above a car port, bathroom, laundry and open kitchen, Traditional houses did not have glass or fly wire, this allows full natural airflow. Mosquitoes and insects can be a problem and insect nets over beds are often required. Verandahs prevent the sun from shining on the walls, and usually have herbs and plants growing in them to the increase shade. Sometimes verandahs are so wide that there are no inner walls. I have 37°C in the carport at 4am in the morning. Thermal bricks hold the heat making the house hot at night. This choice is related to whether the temperature drops significantly at night. Concrete block houses do not cool at night in Thailand, and need airconditioning. The break through is the Venturi effect of the roof. I need to see statistical evidence of the increase in air flow. I am sure it would be an improvement.
in india they use a woven drape made from vetiver (aka khus, Chrysopogon zizanioides) roots which is periodically made wet with water using spray guns to keep cool since before air conditioners were invented
Many old buildings in Europe, like churches or monasterys, are build with stone walls of like 3 or 4 feet thickness. They stay cool all over summer as when the stones are finally heated up, summer is over.
Looks great. I'm sure Nature gave Africa enough grass and plant species to make the surroundings beautiful too. They might even yield a tasty fruit, or two.
Ambient temperature will still be the same with shading, the surrounding air mass remains constant temperature. THe only thing shading does is to reduce the direct heating by solar impingement, which does aid in the indoor comfort levels but if the air is hot enough it is just plain hot. Engineering like this can lessen the need for heat transfer devices but they have a limit, sooner or later some form of air conditioning is indicated for human comfort.
I'm watching this video from my earth sheltered, partially underground home in the Ozarks, so I'm particularly interested in passive design. I've often wondered if underground buildings are feasible in very hot climates like this. For instance, our design had to focus on surface water management and collection because we get a lot of rain. I imagine flooding during a raining season as a limiting factor for underground building design.
solar panels also act as a sun shade with ventilation between the panels and roof, in addition to generating electricity to power the building during daylight
I was hoping to find that information here in the comments. Personally, I don't need years of data (although I definitely see the value in that), but a quick example comparing outdoor and indoor temps would spark further interest.
The section at 2:53 - This refers to the angle of the sun ( *NOT the temperature!* ) Apologies if this has caused any confusion. The C was not meant to be there! 😅
Oh no, it had to be my comment, so pity 😂
Its called a safari roof landrover did it on their vehcles 50 years ago all but a little cruder due to the vehicle shape.
I was just about to ask about that, I went back over that section a few times to see if I missed you referencing temperature caused by the sun's angle with the ground
When people talk about "smart buildings", they often mean buildings with lots of sensors , electronics and complicated systems to regulate conditions inside.
But truly smart buildings begin with designing a building so it doesn't need all of that or at least most) by placing relative to the sun, providing shae, using materials that absorb or release heat as necessary.
In this sense this school is a particularly smart building
The hard part is to figure out hot to make it simple. When you see the design and people say: ahh this is so simple...yeah when you see it working, it is 😂
Exactly. I'm going to try to design some cool new, walkable towns with everything like this in mind.
Good point! The truly smart part is working with Nature instead of against her.
For those who live in RV campers, they can tell you that adding a shade over the camper makes a massive difference when trying to keep cool. Wondering why this idea isn’t utilized more in the desert southwest of the US and other regions.
On us Mexico boundary they build houses with dome roofs with oculus small window which serves as hot air evaporative.
I live in the desert southwest near the border with Mexico, and every year in the Spring and Fall we are treated to very heavy wind storms. We often see sustained winds of over 50 mph during the day that go on for many days, and an over-shelter like the one in the video would have to be very strong to withstand the winds here.
We do use woven plastic mats stretched between poles like heavy dining flys over outdoor structures like playground sets and carports, but they only last a few years before they need to be replaced.
Also, passive solar cooling stopped being a thing here when everyone got electricity. I'm not saying that passive solar cooling wouldn't be a good thing down here, just that it was cheaper to use existing building designs and hardware common in the rest of the U.S. than it was to design unique buildings for this region. Don't forget that price is always an important factor in building construction. It was cheaper to do what was already the standard in other parts of the country, and just run the evaporative cooler during the day to keep things cool.
P.S. In the past we made buildings here with thick walls made from adobe, and they were very good at maintaining a liveable temperature inside them, but they also required a lot of upkeep, and the nature of the material limited what you could do with it.
@@whistlingsage9817 wind speed is good at your end so why not you try wind turbine. it will spin all day/night and contineous source of electricity.
if your weather is hot only and not humid than evaporative cooling is best n cheap for you.
Many camp resorts in Florida use this
It's not uncommon for people to have a fully covered porch or an "RV port" over a single wide.
Another common thing I see in the desert is a second steel
roof to act as a radiant barrier. This is often done as part of roof repairs after the spring winds.
For once, a good, practical, building wins an architectural award.
It wins a dubious award only open to Muslims?
local people solving local problems with global knowledge - thats the past, present and future of human kind.
I love Francis Kéré s presentations especially in german they have this positive and enthusiastic energy
Locals must be white. Whites were making bricks in the video.
Yes, and by working with Nature!
The point with the thick tombe walls is that the heat dispersed at night keeps the rooms pleasantly warm at night instead of too cold due to too quick heat dispersal. This makes optional night time use of these rooms practical as well.
Thank you for that observation! I was wondering why on earth the architect would want to use a heat absorbing material instead of a heat reflecting one for the wall of this building. So, it’s about regulating temperature, not just cooling. That makes it even more interesting.
Im a ventilation expert and business owner bringing natural cooling to the forefront, for people with and without much money. Love this story and yes the Venturi effect, convection abd thermal breaks are the key. Passive is the future.
Frank lloyd Wright houses have been working like this since the 40s and John lautner also. FYI this isn't that new, it's just people actually pay attention to it now
@@trainwreck420ish exactly, its new to many not to history. Same with WHF(whole house fans) 50 year old tech making a huge comeback. People just dont know what it is and i remind them its tried and true NOT new
@trainwreck420ish Do you have any resources that you recommend to learn more about passive heating/cooling? Books, websites, articles, physics concepts, literally anything. I'm going to build my first home on a budget next year, and looking to explore ways for passive heating/cooling. I'm very interested in geothermal.
@nullobject7966 yea, here in TH-cam. There's thousands of hours of architecture and especially mid century modern architecture. I am biased towards frank lloyd Wright and John lautner as mentioned. The two wrote books about organic architecture and the reasons for building such a way. Also Albert Frey and Kendrick Kellogg are awesome as well. There's a quincy Jones Richard neutra and meis van Der Rohr. Try to find mid century modern architecture and stuff built before the widespread adoption of ac. Also Africa has been living for thousands of years without having air conditioning. Also Muslim countries have awesome technology for beating the heat. Towers and domes aren't just for looks.
I once thought of a design here in the US for a mobile home park. Set up a solar panel system on top of the mobile homes that cover the entire roof, and have it raised to allow air flow between the roof and the panels. It would achieve three things. First it would be an entire electric power plant. Second help cool down the trailers. Third protect the roof of the trailers from rain which could over time leak into the trailer. What I didn't think of was an airplane foil.
This is a great idea!
And perhaps you could sell any excess energy produced to power company.
Good idea but.... Roof fires...
Mobile homes are the worst type of housing. Why make a carport for a mobile home when you can just build a real home without wheels under it and a design in all of the natural ventilation and insulation?
Mobile homes make IKEA furniture look like fine-quality furniture. Nobody should permanently live in temporary housing.
I’ve thought of that for parking lots at the airport. Miles of usable sunspace.
We need much more architects like him!!!
This is a great common sense building. Thank you for presenting it to us. The ram used to make those blocks is an easily dismantled UN design that can be welded together in just about any steel fabrication shop. The basic model is powered by one person. No external power source required. The blocks are moist loam with around 3-5% cement and are air dried for a few weeks before being laid. I've been to a course on this tech and it's fascinating. Look up the CINVA ram for more information.
They should do experiments to see if the can handle long term water saturation, if so you could wet the wall and it would be 10-15% cooler. I've been interested in passive homes since 1967 watching real hippies building a house of mud bricks, just as a interest over the years. I tiled swimming pools in the SW USA, thousands of them, in 122 degree F, near the end I would put up a 40'X20' 70% shade, like a knit nylon, and even had 12+ tiny misters. And only swam-coolers at home. I live past the 45th now and think why people don't build houses alike the arcane Russians with a central huge mass of masonry for the wood-stove/oven. The thinks I think of baking or freezing...
In SE Kansas we have an average summertime high of 93 with humidity. It's hot. But we pay no attention to natural solutions. We could learn from this design. Save a lot of energy.
This roof structure might not stand up to the storms we get in tornado alley. I would love to see thermal mass get more attention though. Earth sheltered buildings are much safer in a tornado as well benefitting from the thermal mass.
@@beth8775
I visited an “Earthship” rammed earth house in New Mexico during August, about a dozen years ago. It was 91 outside and 73 inside, mid afternoon.
Well "...we pay no attention..." because capitalism wouldn't have it any other way. There's 300 million Americans, get one dollar from each of them once and you're wealthy. Get one dollar (or more) profit from each of them every month and you can own a television network and some Senators.
And what about strong winds? 🤔🤔
Current heat wave is well past that. Any future design will have to take climate change into account.
If you want to see these techniques on an architectural scale, visit Taliesin West in Scottsdale Arizona. Frank Lloyd Wright designed his winter home and school with these techniques. He used skills developed by the long past native people in the desert southwest to use on the site. Anytime you are in the Phoenix area, please take a tour. It's very cool.
Even my cats know laying under a car in the summer is where the cool breeze is.
Outstanding. Think outside the box. Rely on AC and suffer when the power goes out.
Fortunately the solution comes in the same package as the problem. The same sun that creates the heat provides also the solar energy to run AC. With today’s technology, cooling is a much smaller problem than heating.
Find the hottest side of your home. If you put up a shade there, you will cool your entire home. It can be a cheap solution, try straw mats, bamboo shades or some kind of cloth. We cool our home with one window unit for our 3 bedroom house. Shades and awnings need to make a comeback.
Thats pretty much the average temperature where I work in Australia (mining, remote areas) and we often use similar building strategies in the outback. The second roof is a common one. We also sometimes add native vegetation to encourage the development of microclimates.
That's my favorite kind of intelligent building. Kudos to Diébédo Francis Kéré!
Yes! Diébédo Francis Kéré has gifted this community with a beautiful school building ☮️ I hope more can be built to benefit more children!
A friend of mind in Washington State has a triple-wide manufactured home. He added a “pole barn” roof 4 feet over his house. It not only provided shade in summer, which sometimes topped 105 degrees, but helped in winter as well with the “snow load”. He did extend the chimney from his fireplace up and through the added roof height to keep smoke from being trapped inter the added roof even though the “pole barn” was open aired on the sides, smoke could still be caught under it on no or low wind days. This was back in 1988……Cheers
I wish there was some data provided in this video about the temperatures experienced within the building itself.
And drop the temp by another 5 degrees by planting trees and plants around the garden.
Why didn’t they add more greenery and tree water combinarn*
They may not grow
@@vsubhutiit’s arid. They probably didn’t have much water
Fantastic and heart warming to see great thinking going into solving a local problem. Not looking for awards and accolades - just fixing a local problem and helping locals in a practical, wonderful way. Fantastic! Bravo!
I like the concept. I wonder if that location experiences hurricane force winds. The external roof looks like a wing that could experience major lifting forces in such conditions.
Zero hurricanes there
Glen Murcutt has done similar work decades ago in Australia's Northern Territory, where cyclonic wind forces are a major consideration. It's a different climate with different solutions, but it can work. Look it up.
Theoretically the upper roof would be pushed down onto the lower roof because of the low pressure between them caused by the Venturi effect. Now whether that's really true, IDK. They'd have to measure the pressure above and below the upper roof during windy days.
@X4R2 I was thinking the other way around. Higher airflow above the upper roof resulting in low pressure and slower speeds below the upper roof resulting in high pressure. The pressure difference resulting in the air below the roof going from high pressure to low pressure causing lifting of the roof. Like an airplane wing.
@@jasondoust4935Glenn Murcutt sadly still not respected for his wonderful designs. I attended a lecture of his years ago - very inspiring 👍
As I watched this I was hoping for a temperature for the area which was said but, I wanted an internal temperature from inside the "no A/C needed" building. I think with the smart design, and available materials it's much better than normal building practices. However, I would venture to say it's probably not in the 70 degree range for an air conditioned structure. Very thoughtful!
maybe not in the 70 degree range, but the heat-load is greatly reduced, and that means less A/C is needed to cool to the desired temp! :)
@@GlueTubber Exactly what I was saying. Is it 30° cooler or 5°. Orientation of a building with respect to sun exposure can do a lot. Trees can produce almost miraculous results. Just wondering about the before and after.
Brilliant! I love seeing passive cooling ideas.
Roughly 20 years ago, Dwell featured a home in the Southern California desert near Joshua Tree called the “Desert Shed.” It featured 3 main features: 1. A concrete slab that was at least double the amount of a normal 1500sq ft home with the house built directly on top of it (to reduce temperature swings from such a massive slab), 2. A metal roof built up over the house for the previously mentioned venturi effect, and 3. The house was south on the slab with its windows facing south to gain solar energy in the winter and take advantage of full shade in the summer.
It's been over 100 degres (F) in my area for 3 weeks, hitting highs of around 114. We could definitely use this type of design. (Sacramento CA).
I love when simple solutions are intelligently applied. Bravo.
Thanks for this video. I’ve known before about this project, but your explanation about it, pointing out why one option was better than others, was great.
They study in schools in the heat because they have no other option.
Unlike most readers here, I've actually been inside a school on the edge of the Sahara where it was 112F in the shade and no electricity around. The only AC I saw that entire week was in my room in N'Djamena, and in a pharmacy that I had to visit when I got sick. (Pro tip: Don't drink the water. And don't eat the food).
And yes, people gathered in hot buildings to do their school and their work ...because there's no other option.
But if someone wants to put a swank roof on these buildings and cool them down, heck yeah - let's have more of it!
Wow, built such a great design with almost no infrastructure is a great achievement!
I first heard about these grass roots concepts in the Barefoot College Ted Talk. Love this stuff.
Yeah Africa had mad houses. It’s cool during the day and warm at night cuz it gets cool at night . It’s just perfect
Dr. Ye Tao uses similar approach to cool roofs in Freetown. Moreover, he ads reflective layer on roof to reflect more sun rays back. Incredible how simple solutions can be so effective. Hope more architects will learn such hacks 👍🌍🕊
95F is a cool day in western Texas to Phoenix AZ. In the southwestern area of the US temperatures can exceed 120°F / 48.9°C, Architect Frank Lloyd Wright designed a few buildings located near Phoenix to be cool in those high temperatures. Also homes in the American in southwest once used construction principles that allowed air to flow which kept them cooler. The Arabian area also built structures that stayed cool during extreme temperatures.
Switch uses this same technique for their data centers here in Las Vegas. A double layer roof, high albedo layer (on top), and they use cooling towers to push cool air between the upper roof and the lower roof.
This is amazing and inspiring! Great strategy for living in hot and extreme climates. Another good strategy is dome roofs. And my favorite strategy of all is building (and growing food) underground, like with earthships, hobbit holes, and the Forestiere Underground Gardens, in Fresno, California. The Underground Gardens are an excellent example and definitely worth checking out! Thank you for this video!
02:55 Angles are measured in degrees or radians, and not in degrees Centigrade.
Well spotted! The C was a mistake! Those are meant to be the angles of the sun ☀️
You should also mention that the whole point of the high air speed Venturi is to cause a low pressure zone that will literally suck hot air up through the perforated ceiling.
lol, those are degrees celestial!
Saw a few years ago a television programme by the British adventurer / outdoors man Ray Mears. He was in North Africa around the Sahara Desert. He had a Land Rover parked up. He said that he would normally use two parachute fabric covers spaced approximately 30cm apart. He said this kept the temperature down a considerable amout in comparison to a single layer.
It's like Texas! I hope to build a new small home soon. I will keep these tips in mind. Heidi
Simplicity is still the ultimate sophistication.
Love it!!! Please do more videos on passive cooling designs. Thank you!
Very glad you like it! More to come 💪🏽
I've seen a similar design on a winery in Mosel, worked great. Cool inside even with 35 deg C outside,
The best part about passive designs is you can slap air conditioning on top of them and it'll barely run, but when it really does get that hot where your passive design allows the temperature to rise past 80F, you have the option of turning the AC on. Sure, without the insulation typical in the AC paradigm of an American home the AC will be less efficient, but with all of the passive energy savings you already have, that's okay.
Keep it simple and stupid! No one knows more to use this phrase than Mr. Kere! Whe can learn a lot from him! Thank you for your ideas!
I believe the phrase you’re looking for is, “Keep it simple, Stupid!”
Thank you for highlighting this genius design!
You forgot to mention that the earth bricks also release heat towards the classroom for many hours therefore the perforation of the ceiling so this heat is also released out of the classrom
Absolutely brilliant ❤❤❤
I mean, this is the real deal. Here we are in America designing houses. I’m building them pretty much the same way with the same heating systems and insulation stuff in the past hundred years. But there’s so much we could be doing to work with nature, and said I
Listening to this, even reading a telephone book, would never bore me.
This system works best in arid climes where the humidity is low. With high temperature/high humidity situations, natural cooling is much harder to achieve, though this might be as good as any.
A good number of years ago I did some thermal analysis with SolidWorks Flow Simulation, a tool used for analyzing products like computers and phones, to do some basic probing on the idea of a shade over a roof. What I found was that there needed to be a pretty good size gap, similar to the one shown in this video, to make the concept effective. It is typical of passive flow, density driven flows need a ton of space because the driving force is low. If wind were the primary driver, you could reduce the gap, but then the strategy falls down on a calm sunny day. The holy grail is a passive geothermal heat pipe that uses water as the working fluid. Heating from above, cooling from below is stable though, and can't be used to drive circulation, the driver being changes in density. Ever wonder why the stuff at the top of a cooler can be warmer that the stuff at the bottom? Heating from above, cooling from below, flow shuts down, and with the thermal conductivity of air being so small, the column stratifies thermally. Fun fact, the thermal conductivity of the materials that thermal insulation are made from is actually pretty high compared to the insulation as furnished. The reason is simple, insulation has one job, keep air from moving. The drag induced by insulation nearly eliminates the effects of density driven flow. The Achilles heel, wind loading on the shade is high in storm conditions, so designing it to withstand high winds is probably cost prohibitive. Probably better off designing to be easy to repair than resist crazy wind that only comes around once every 10 years.
I live in areas where temperatures soar upto 48c max and 40c on average. One of problem is low air flow. In desert air flow is good.
But biggest problem for us is rainy season with too much humidity. Hot weather lasts for 2 months but humidity weather lasts 6.5 months.
Is there any passive cooling method for humidity free homes ?
I think there's a video from India about cooling without AC. Something about creating a wall of clay cones shaped like bottles.
@@raj66kas Yes an Indian engineer created terracota clay based waster cooling system. But its for hot weather only. when you use water than humidity increases and i need a solution for humidity.
That is challenging. What energy sources are available? Are there streams or rivers to use for hydropower? Is there much firewood? Is there any sunshine during those 6.5 months? Wind power?
Reducing humidity typically requires compressor-based air conditioning, or desiccants that need to be dried generally with a heat source.
If you live near the ocean you could pump very deep cold ocean water up and humidity would condense on it. The dew point of the air would be reduced down to the water temperature.
@@mikeguitar9769 Thanks. But i don't live near an ocean or water stream. Only option left for us is compressor based air conditioners.
desiccants can be a good starting point for me. I live in Pakistan and pink himalyan salt mine is here. salt mine is also humidity free and has pleasant temperature inside. Thinking about using salt slabs or stones. Place salt in room attach a fan let's see how much humidity it can control. I also found out that there are some salt rooms made for therapies and they have no humidity inside.
"35°C? Hold my beer." - Philip, SD
Great information. Thank you!
Brilliant!
I wonder about heat mitigation all the time with my businesses. We rely so heavily on mechanical HVAC solutions in single floor plazas. When an HVAC isnt working correctly the flaws in the structures we have to passively mitigate heat or cool are extremely noticeable.
Planting a tree to give shade is a 50 year solution and not practical in a commercial sense. So having a secondary roof is something i def would like to explore
Very efficient, functional and beautiful design.
Very well presented and thought provoking. Thx
I'm loving that roof!
Such an elegant solution! The architect was excellent, and so was the explanation. One other thing about air conditioning, it dumps the heat taken out of the inside of the building to the outside, making areas around the buildings with a/c even hotter. Also given human nature where when a/c is available they often crank it up so it is freezing inside, instead of just comfortable, wasting energy. This was a great video, would have liked to know the temps inside the building when outside is 40 deg.C. How much it can cool?
Give us the statistics: Temperature in the sun, In the shade, and with the Venturi roof.
Is it an open roof gap over a ceiling built as an inner roof? Are there vents in the ceiling? One side elevation shows a flat inner roof and curved outer roof, another shows a curved inner roof and curved outer roof. Which is it? Ventilated roofs over ceilings are common in hot countries.
In Thailand the gable angle is very steep, about 50°, to allow the hot air to rise. Fans are used to create a breeze.
In Thailand often a flat roof becomes an open air top floor over which a gable roof is built for extra shade, This floor is commonly used for clothes drying, which in itself reduces heat required to evaporate water. Bird wire is needed to stop flocks of birds nesting and pooping.
The houses are often raised one floor height above a pond of water, or in modern times, above a car port, bathroom, laundry and open kitchen, Traditional houses did not have glass or fly wire, this allows full natural airflow. Mosquitoes and insects can be a problem and insect nets over beds are often required. Verandahs prevent the sun from shining on the walls, and usually have herbs and plants growing in them to the increase shade. Sometimes verandahs are so wide that there are no inner walls. I have 37°C in the carport at 4am in the morning.
Thermal bricks hold the heat making the house hot at night. This choice is related to whether the temperature drops significantly at night. Concrete block houses do not cool at night in Thailand, and need airconditioning.
The break through is the Venturi effect of the roof. I need to see statistical evidence of the increase in air flow. I am sure it would be an improvement.
Intelligent design. It just makes sense!
And now ad a super white coating on the outer roof.
Very well explained. Thank you.
One can only hope that every video on the Tube has English so clearly spoken. Thank you.
I love Francis Kéré s presentations especially in german they have this positive and enthusiastic energy
Non à l’anglo-suprémacisme ! Faites vos vidéos dans votre langue préférée et que les anglo-suprémacistes aillent se faire mettre !
Why English?
Why don't you learn other language as many of us around the world do?
Your loss.
This is nice. Thank you for sharing this
It would of been nice to know the temperatures actually achieved inside the building as this is the real proof of concept.
What a wonderful job.
I like being able to go to my basement in the summer .
Fantastic!!!
So what is the temperature inside of the classroom?
in india they use a woven drape made from vetiver (aka khus, Chrysopogon zizanioides) roots which is periodically made wet with water using spray guns to keep cool since before air conditioners were invented
Many old buildings in Europe, like churches or monasterys, are build with stone walls of like 3 or 4 feet thickness. They stay cool all over summer as when the stones are finally heated up, summer is over.
Great innovation. Bravo!
What was the average temperature change from inside the building to outside?
Love this. Just wondering how the top roof holds up to high speed wind gusts like those form storms.
So interesting, well written and explained.
Old Land Rovers used this idea, too, with a second roof layer gapped above the main roof.
Cool, in every sense of the word.
Well done team!
Looks great. I'm sure Nature gave Africa enough grass and plant species to make the surroundings beautiful too. They might even yield a tasty fruit, or two.
Exceedingly interesting!
I wonder how underground/partially underground building would pair with a double roof, and how to modify one for places that need seasonal solar gain.
Ambient temperature will still be the same with shading, the surrounding air mass remains constant temperature. THe only thing shading does is to reduce the direct heating by solar impingement, which does aid in the indoor comfort levels but if the air is hot enough it is just plain hot. Engineering like this can lessen the need for heat transfer devices but they have a limit, sooner or later some form of air conditioning is indicated for human comfort.
I have open air ground mount solar panels 6ft high. They get 150-175⁰ underneath is So. Cal sun. Without air movement plants still wilt.
I'm watching this video from my earth sheltered, partially underground home in the Ozarks, so I'm particularly interested in passive design. I've often wondered if underground buildings are feasible in very hot climates like this. For instance, our design had to focus on surface water management and collection because we get a lot of rain. I imagine flooding during a raining season as a limiting factor for underground building design.
solar panels also act as a sun shade with ventilation between the panels and roof, in addition to generating electricity to power the building during daylight
What is the temperature difference insiide vs outside? Put solar cells on the roof to use for an AC. Collect rain water to store from the roof.
Energy star score, that's amusing.
This kind of architecture is called "using common sense". We need more of this not only in realty, but also everyday life.
may be an exemple, with an thermometer on the roof (or outside) and one in class (inside) to see the difference in temp, will be more useful :)
Greetings from Mozambique, Tete Province, Over here temperatures can reach 46°C normally
I missed the part that told just what the "cool" temperature inside is.
Good video. Liked and subbed.
Dirty Simple and Beautiful...
As Diamonds in the Rough should be...
Right here in sunny California, we are having temps over 110 F
What is the delta t offset inside to outside?
Sounds good. But we'd love to see some actual historical indoor temperature data taken over a few years time. How hard is that to do?
Yeah. Without this data it's only bla bla bla
I was hoping to find that information here in the comments. Personally, I don't need years of data (although I definitely see the value in that), but a quick example comparing outdoor and indoor temps would spark further interest.
About as hard as flushing the toilet in public restrooms 😞😨
@@iron4ig you don't need data, just asked the kids using the facility.
Just what I thought. I don't say it doesn't work, I just want to know what they deem comfortable. A wonderful design in any case.
Nice
Buckminster Fuller used similar natural ventilation in one of his house designs.