Hello everyone, welcome to Daily Life Hacks. In this blog we will discuss how to keep roof cool in summer-almost zero investment. In internet there are many tips and tricks to keep roof cool in the summer. But those many are not affordable for many people or they don’t want to spend money for just to keep their roof cool in the summer or some people have future plan to increase stories in their building so they don’t go for permanent solution. In this blog we will understand why our concrete roof stays hot even after the sun is set. Is there any way to keep our roof cool in the summer without spending much? Before discussing this I want to clarify one thing here is that this technique can be applied to flat type roofs of any kind. However, those who’s roof is week and also has a chances of water leakage shouldn’t apply this trick.
Why our concrete roof is still hot even the sun was set- it is because of the property of the concrete towards heat. Concrete has a property to absorb and store heat for long time. That’s why it is said, concrete has a high thermal mass. In day time sun light, which is nothing but energy in the form of light fall on the concrete roof and is absorbed by the roof. These energy of sun light is further transformed into heat and stored in the concrete roof. Thus the energy is stored in the concrete roof and because of these energies in the form of heat the roof becomes hot for long time. As we know concrete has a heat storing property so the energy is trapped in the concrete as heat.
How to keep roof cool in the summer-almost zero investment:
If we can release these energies from the roof, the roof will be cool. How to release these energies stored in the concrete by means of reducing the temperature of the roof? Do you know in the summer why our body sweat? Sweating is for many reason, one of those reasons is to keep our body cool. We wonder how? Cooling our body by sweating is an evaporation cooing technique. Evaporating water in the form of sweat will release energy from the body and keeping our body cool. That is why in the summer during sleeping time if we sweat then we fall asleep very quickly because sweating releases energy and we get tired quickly. I experienced this many times. Anyway here our objective is to release energies trapped in the roof in the form of heat. So we will use evaporating cooling technique. To cool our roof, we can give anything on the roof which must evaporate quickly and is available easily. We can store a layer of water on the roof for all time so that when it is sunny day, water can evaporate all time releasing energy with them and keep our roof cool.
Next we will see how to make it cheaper. To make a 1-inch water layer on a 1000 sq. feet roof we will need nearly 900 liters of water. So pumping 900 liters on the roof will consume electricity and money. So we will think for free water which comes from heaven. Rain water is free in the summer season and it rains pretty often in the summer season. To store rain water on our roof first we need to confirm that the roof’s edges are raised.
There must be an overflow pipe or a water drainage pipe. We will make this drainage pipe out such that whenever it will rain, after the rain 1-inch of water layer would be left on the roof of our building. I will show how to make out the drainage pipe bellow-
If drainage pipe is horizontal- In that case, we have to attach another piece pipe fits in drainage pipe with an endcap on the other side. Pipe should be cut horizontally keeping 1-inch bellow and cut portion should be above. Note that some cut-off portion should not be inserted in the drainage pipe and pipe should be fitted properly with adhesive solutions. From the bellow image it will be much clear-
Let’s see what will happen when a thin layer of water on the roof and the day is a sunny hot day. When the sun rays will fall on the water and energy with them, then the water on the roof will absorb the energy of sun rays and will continue to evaporate slowly. Thus the energy will be radiated in the form of vapor and roof will not become so hot. Roof will not store so much of energy in the form of heat. At night we will be so thankful to the evaporating cooling technique. If there is no rain for a long time, then we can use some commercial water pumping on the top of our roof as well.
Conclusion:
The conclusion here is to keep our roof cool in the summer though there are many techniques available. To apply those techniques, we need to spend a lot. But is a cheapest technique which we have discussed above. This technique is called evaporating cooling technique. In this technique we use rain water stored on the roof to make a thin layer which is eventually vaporized by the energy from the sun rays and radiates the energy which supposed to be stored in the concrete roof as vapors. This is how we keep our roof cool in the summer.
FAQ:
1. How do you cover a roof to reduce heat?
Answer: To reduce heat we can cover a roof with insulating white paint. Insulation will resist the heat to travel in side our house and white paint will reflect maximum sun rays. Also we can add thick layer of reflective gravel on our flat roof.
2. What is the best material to make roof to keep it cool?
Answer: Thicker material is best for the roof because if it is thick then heat will travel longer to reach inside. Keeping the material price in mind we normally use concrete slab which is thicker and heavier.
3. How do I keep my RCC roof cool?
Answer: There is a drawback with concrete roof that it absorbs heat and stores it for long time because concrete has a high thermal mass. So to keep our roof cool on a sunny day we can make a thin layer of water on the roof so that the water absorbs the heat and evaporate eventually, thus the roof gets a radiating mechanism to release the heat. For more details, kindly read the above blog.
4. What is a cool roof coating?
Answer: A cool roof coating can be a paint coating which should be heat insulator in property and white in color.
5. Why do roofs get so hot?
Answer: Specially the concrete roof gets so hot for long time because concrete has a property to absorb heat and store. That’s why it is said that concrete has a high thermal mass.
