HomeНаука и техникаRelated VideosMore From: Down To Earth

Cool roofs: How to beat the heat for top floor owners: Ep3 New Vastu with Ashok B Lall

1206 ratings | 126222 views
Top floors can be excruciating during the Indian summers. But there are ways to stay comfortable on top floor houses. Ashok B Lall gives his tips on how to beat the heat. Ashok B Lall is one of the foremost green architects in the country. He is the Principal of Ashok B. Lall Architects in New Delhi, India. He has practiced sustainable architecture for over 3 decades.
Html code for embedding videos on your blog
Text Comments (50)
GST2 S (10 days ago)
Aluminium foil advice is slightly wrong. The reflective side should face down, with an air gap below it. You don't want dust to gather on the foil, else the effectiveness of the foil diminishes greatly in a relatively short time as dust accumulates. It also helps that the foil is on the hotter side so moisture is less likely to develop on it by condensation. It may be surprising to some that it will still be as effective when the reflective side is facing down (there are some good youtube videos explaining why this is so).
Trishanku Verma (27 days ago)
The reason why unemployment village architects of Vishwakarma's helped with Attic which was atleast 4-5 feet in height. The roof was filled with mud loads of it. Come visit north Karnataka houses and how they keep it cool. Education is bascially about over engineering and polluting our environment. Why are these builders building structures like this. A canvas canopy on top the roof should help cut out some solar radiation or just plain aluminium sheet canopy.
Dilip Deshmukh (2 months ago)
pl. contact
Annie Anon (2 months ago)
Has anyone tried watering the roof after sunset? We used to do it in my old house, thinking to do it this year in my apartment...thoughts?
Luis Solano (2 months ago)
I want to make interior and exterior cool roof emotion for walls and coating for the walls let me explain and guild you threw this process, the emotion penetrate threw every microscopic hole on the dry wall leaving the interior thermal so let say you live in Alaska or big bear, as soon as you turn on the heater it stays thermal temperatures for the interior of the house, by adding every cool roof color available including white and grey and every bright color that can be used as resistance will be available and apply a new way and methods of painting houses, this is an update, painters will give you better warranties for a job
Ammad Asif (3 months ago)
Thanks with lots of respect
santosh r (4 months ago)
Roof garden with some green net is great .. LAWN is a NO NO ..
wilwad (4 months ago)
I live on the first floor. It's boiling hot come night time. One day I touched the wall that faces the sun from the afternoon until sunset, I felt the heat. That's when i realised the wall was radiating heat absorbed from the sun. Just as you explained.
Durga Hema Kumar (6 months ago)
Try any idea nt bttr
jervic Bautista (6 months ago)
We can reduce global temperature if we paint all our roofs white 😉 Just like ice and snow in north and south pole which acts like a giant mirror reflecting heat and uv rays back into space.
Philip Goh (7 months ago)
I think 50mm insulation materials should be placed above the Alum Foil. The infrared heat from the roof will pass through the 50mm insulation material and be reflected by the lower placed alum foil. The hot air in the roof space via convention current circulation in the roof voids will reduce conduction by the 50mm insulation and reduce heating up the metallic alum foil. If the alum foil is placed above the insulation, it will be heated up by conduction and radiate down into the ceiling and into the room.
GST2 S (10 days ago)
Yes, and the foil should face down. From top to bottom, it should be concrete slab, [polystyrene] insulation, aluminium foil (shiny side facing down is fine, so no dust accumulates on the foil, which would massively decrease its effectiveness), then an air gap of at least 50mm (but more if possible), then the ceiling.
Henonaga (7 months ago)
The only solution is air conditioning or a strong fan. The heat is more concentrated on the top floors.
Josh Wilson (8 months ago)
If you live in a temperate or cool climate and need a dark roof to absorb heat in the winter you can hang light-colored fabric over the roof in summer.
Farhan Belim (8 months ago)
Paul Langford (9 months ago)
Put an earth roof in place, with lots of vegetation. Or make a courtyard with a parasol roof.
Varun Saraf (9 months ago)
thank you Mr Lall for such insight
m721ac (9 months ago)
Paint the roof white keep it clean, or grow a garden, or 5:14
Sir please make your videos in hindi so that more and more people know and understand.
Spock (10 months ago)
if already in apartments then go from 04:34 and there is no vaastu involved! standard HVAC concepts!
Subramanya Nanjundaiah (10 months ago)
Our choltry is some heat. How its come down the heat. Sir
Bhanu Prakash (10 months ago)
Directly watch from 4:36
Chapandaz Sain (4 months ago)
+Peter Griffin I wish I could check your comment before watching the video..! ! !
Peter Griffin (5 months ago)
tnx life saver
Spock (10 months ago)
true that and there is no vaastu involved!
Ironbuket (10 months ago)
5:16 The suns rays are going straight through that concrete...
kouser shoukath (10 months ago)
A typical HVAC Concept
Spock (10 months ago)
true that and there is no vaastu involved!
Refuso Againo (10 months ago)
Only a few years ago ideas like putting plants on the roof we're intriguing but fanciful. Now they may be inevitable. Our house is in the low Sonoran desert where it was 120F last summer for over a week. (Daily high temp) I've just finished installing a radiant barrier on the part of my roof that gets the most sun and it's working already, we can physically feel the difference inside the house when the whole truss/roof structure's temperature is reduced. I can only guess at how much radiant heat is being reflected and how much is still being gained, but it's obvious that it's one of those simple, relatively cheap (if you're building a roof anyway) and effective methods we've yet to deploy seriously. My information is that it will be code in the California 2019 version. The next thing we've neglected due to a variety of superficial reasons is heat pumps, both ground and air source. Jaguar uses a tiny one to heat the cabin on it's latest $100k electric car, because they are efficient. Some water heaters use (smallish) air source heat pumps to heat the water and cool the room it's in. Those lot-line setbacks of 10' and 15' could be used to place underground cooling pipes. You can insulate them (on top only!) before backfilling, to further increase their cooling effect. Our 50 year old stucco bungalow has the same volume of concrete in the form of stucco on the outside, as the slab foundation the house sits on, according to Sketchup. (3D software) Where it is, it works against us, adding to the "heat islanding" effects of concrete around the house generally. (and throughout the city) By insulating it on the outside with polyisocyanurate (fossil fuel product) (3"=R 21) you capture that thermal mass, where it then contributes to moderating the inside temperatures instead. (existing wall insulation has to be removed to expose the stucco to the conditioned space) Next we need a natural air flow system to vent excessive hot air and replace it with cooler air from under the house or near it's northern perimeter. Being at latitude 32.4 means that we have a heating load in Winter also. A mild passive solar design takes care of that and shares many of the methods used to make the house cooler. This is not done yet, I'm just installing the radiant barrier and solar array (5.1 kw) now, and the rest will take place as we can afford it, or as the temperature dictates. We're not allowed to use city water for lawns anymore, but a roof lawn would be monumentally ironic, if one used re-cycled water. This is Palm Springs, put a putting green up there, or a 'spa'.
Prash DOnekal (10 months ago)
D'oh! Sir you are like captain obvious - we already know all this.
Manoj Mehrotra (11 months ago)
Nice indeed better to analyse than to blindly follow vastu good one
Shaik Shahnaz (11 months ago)
You have a lovely home. Interiors are very tastefully done.
paresh prajapati (11 months ago)
Thank you sir
aslam khan (11 months ago)
oiyabastard (7 months ago)
aslam khan. Cement is a one component in concrete it's a powder please tell me how cement powder is advantages to global warming you dumb shit don't you know what HAARP is it's in trolls whether it is a real thing why don't you fucking Google it the motherfuking elite controls of whether they make the global warming to control us and control high prices
Cool S (11 months ago)
Thank You so much Sir for Such nice info, we are already made a terrace Garden on roof and it helps a lot. Take Care ☺️
Prashanth Purastu (10 months ago)
Cool S how about water proofing??
ajay trivedi (11 months ago)
ac lagwao or chutti pao (:
Heart H (11 months ago)
sir which paint to buy
Saiful Chowdhury (1 year ago)
Nice. Thanks...
gemkachar (1 year ago)
solar powered air conditioner ?
Jayanthan (1 year ago)
I have noticed in quite a few houses mainly in Coimbatore were they will remove just one brick from the top most layer in each room acting as ventilation and the room is quite pleasant sometimes even during summer without a fan .
Raghu Reddy (4 months ago)
Before 90s ,all houses were like that when we didn't yet start using putty got walls or Colorado paints and not even ACs. Easter coolers were norm. Rooms then used to have 2 or 3 such openings with grills . Buy then there also lot mosquitoes
Fawaz Khan (11 months ago)
Jayanthan pls come to Kerala and visit traditional houses.
Pallab Mondal (1 year ago)
You are awsome sir...........thanks for your information
kanchan kapoor (1 year ago)
Sir u r one of the most soft spoken anchor .and it is beautifully explained.
Deepak Filmy Theatre (1 year ago)
Sir I stay in asbestos roof house.please suggest me to cool down my room temperature.Its really very difficult to sleep during summer.
aslam khan (11 months ago)
Deepak Filmy Theatre bhai this for asbestos https://youtu.be/3RgEbAkVF7c
Vinoth Kumar S (1 year ago)
Thanks for the suggestion sir.

Would you like to comment?

Join YouTube for a free account, or sign in if you are already a member.