A very thick concrete shall be made to prevent heat penetration)
The problem of overheating in farm is mostly caused by the poor construction of roof and ceiling. Either the one who built the roof didn’t understand the effect of heat penetration or simply wanting to safe cost.
There are few ways to prevent heat from penetrating thru the roof and ceiling. One of them is by using concrete. Then again if it is not done properly instead of preventing heat it would create more heat. The concrete ceiling has to be thick enough to prevent heat penetration. In hot area during hot season 3-6” of thickness would not do well unless insulation material being put inside the concrete like sandwiches.
Given the condition that the roof is of zinc material this would make it worst. There are many farms who had applied such technique and later to discover the temperature did fall drastically after they had constructed a concrete ceiling. During hot season inside the ceiling it is like a pressure cooker sometimes the temperature goes up to 60C.
Some said having a concrete ceiling would prevent thieves from breaking in. Burglars wouldn’t be so silly to go thru the ceiling. The Entrance Hole is ideal for them. Unless a grill is being installed at the entrance but I won’t encourage this because it would disturb the flight of the birds.
Some may make a pool above the ceiling so that it could cool down the farm. Make sure it is done properly with water proofing material otherwise water sipping thru the concrete gaps and all the planks inside would be infested with fungus. I have seen this too often all planks are infested.
The pool has to be deep enough and it needs big volume of water if not, it would become hot during hot day. The heat from the hot water from the pool would penetrate thru the concrete ceiling. There were many occasions I tested water in the pools of those failed farms and it reads 45C or more.
So there are bad and good about using concrete ceiling. If you know how to make use of them then it would be to your advantage.
Besides putting concrete on ceiling there are many other ways to prevent heat penetration from ceiling. Styrofoam would be good it cost very much less than the concrete ceiling and you would be surprise if it’s being installed properly it could beat the concrete ceiling in term heat insulation. Beside that it is very much stable and better temperature control during rainy season when wind is strong and chilling.
Other likes wool, bubble foil, aluminum foil etc could be used too but I still prefer Styrofoam.
So the importance of knowing what is to your advantages would definitely help you to build a good farm with good internal environment.
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