you mean this one issit?

you mean this one issit?

This is light weight brick. For me its useless although light.I just used it as partition for my extension room. Only after buy i know its very fragile.Too fragile until i wonder how this thing used in building.Lucky used for partition and i dont hang anything on it like photo frames etc cause i worry it will break.

I say this type of brick very popular in Philippines at low cost housing and rural areas. Maybe due to cheap cost.

you do know what is lightweight brick, right? you do know that they're LIGHT, right?
you know light is the exact opposite of heavy, right?

take a guess. your ordinary clay brick is a heavy brick or a lightweight brick?

but sure, build your structure according to whatever picture on the net and don't consider the load weight.
i'm sure it'll work out for you. 
there's quite a number of solution on the market now.
IBS isn't interlocking bricks per se. there's also interlocking cement blocks. there's interlocking IBS brick (brick sized). there's interlocking IBS blocks. there's AAC block.

never seen AAC brick before. though i'm not surprised one bit if there's also aac bricks selling somewhere.