The ground floor which was almost 250 feet away from the main entrance hole do have signs of birds staying.
In the beginning I feel very strange however upon closer inspection of the BH I then discovered the reason why.
Let me describe a bit more about this wrongly designed BH.
The owner claimed that he was attracted to having a BH about four years ago and dump in about RM 400,000 into his dream BH.
However after four years into operation and two famous consultant came to arrest the BH problems he got only 5 nests.
How unfortunate and no investment return so far.
One great error about this BH was the way it was designed especially where the Lubang Antara Lantai (LAL) were situated.
The so called consultant came out from his "learning" from a very popular Sifu located in a neighboring country that the LAL should be located on the opposite site of the main entrance hole.
Which look some thing like these sketches: