May 28, 2013 - 07:21 AM
Years ago I remember reading an article about a home infested with rats, roaches, etc. and when they tore it down, the critters scattered everywhere. They even had the fire department and many volunteers ready to help try and stop the spreading. They were not successful.
I think it depends on the sheer number of roaches. If you are dealing with a minor infestation of cockroaches, then the spread should not be that bad. What I would recommend is to not try and kill the roaches as they are coming out of the house, (of course you may have to - see next step), but rather to try and keep them from migrating to the home or buildings next door.
The best product to use for this would be Mosquito Barrier, since it is garlic oil and very repellent. Basically, spray the perimeter of the surrounding homes and hope that you repel the cockroaches and they go somewhere else. This is a non-chemical method and would not harm any neighbors, pets or the environment.
The usual approach I assume, would be to have several people outdoors with sprayers and try to spray the roaches as they exit from the home. I don't know how effective this would be overall, as the roaches would not die immediately, and it would take a large amount of chemical such as Bifen to do this.
The best and also the most expensive approach would be to have the house fumigated with "Vikane" which is a lethal gas. This would kill everything inside the house and then you could bulldoze it. You cannot do this yourself. It would have to be performed by a licensed fumigator.
So these are the methods for how to keep roaches from moving next door when tearing down a house. I hope this gives you some ideas. Thanks.