In the washing machine room, there is this floor drain, which drain out water from the washing machine. But, the place has alot of cockroach, especially my first wash at that place. I put ridsect and eventually cockroach is less seen. Nevertheless, there is still this cockroach smell whenever I open the door. I have tried placing charcoal to absorb the smell, don't seem working.

Anyone has any idea how to reduce the smell of cockroach? Thanks

my mom use duct tape to cover the hole.
semi-transparent white duct tape

but, it will still stink right?

Better you call a pest control company to get rid of the roaches. Otherwise the smell will never go away since you can't fully seal off the hole.

I pour boilin water into the drain............

there used to be this small black worm crawlling at the edge of the drain mouth

buy those cockroach's spray ... hmm something like ridsect.. but that one great.. my friend gave one to me to spray my car outcome.. 1x cockroaches RIP
tried that once at home... RIP as well

beside cockroach's spray, get some cockroach's bait, those cxcrch sure disappear.

i got those bait from jusco and change @ 3 month interval

throw a grenade into it..run...shout 'fire in the hole'...

there is some floor grating trap to prevent Cockroach , you can buy from hardware house or those sanitarywares shop .

i figure out that the cockroach smell is most probably cos the room was not utilized for a period of time (like since July last year), after few rounds of washing, the smell actually goes off.....hope it will go off totally eventually.....thanks for the suggestion.....