As you all know by now double walls will help to reduce those heat from travelling direct from external surface to the internal surface.
If these high temperature usually cased by direct sunlight are allowed to travel across the brick and nothing blocking it from reaching the internal surface you will turn your internal wall surface as a heater.
Once these hot surfaces transfer its heat to the room air the whole floor of your BH will be heated up.
The heat transfer usually occur around 10-11 am and will continue to heat up until 10-11 pm.
During hot weather system you can imagine what will happen to your BH.
The recommended room temperature is around 26*C-30*C.
If your BH internal temperature touches 32-35*C you will soon find that your tenants both new and old will vacate your BH.
So once this happened you will find out that all your effort to populate your BH will go down the drain.
You will be very disappointed and do not know what to do.
There is no way to keep those birds inside if you do not stop those heat from reaching your internal wall surfaces.
Have a good look at these two BHs.
You can easily tell yourself that the 1st BH is double layered while the 2nd BH is not.
The 1st BH will have a much better temperature inside while the 2nd BH will have a kind of very high temperature.
If nothing is done to prevent the heating effect the 2nd BH will be too hot and those swiftlet will check out or if the BH is properly design (proper LAL locations) they will stay at the lower floors.
You need to understand that when air is heated up it will be lighter as compared to cool air.
As such the hot air will float up and accumulated on the top most floor.
This floor will be the hardest and hottest.
So how do we control the heating?
Think wisely and find the right answer.
If you don't know call 0177551318