I don't usually do product endorsements but when you run across something that works this well you want to share the info. But I'll warn you - this topic isn't for the squeamish.
Our little house is raised off the ground and we have a great storage/work area underneath. But we've always had a problem with roaches. Not those little brown banded jobs, I'm talking the big, aircraft carrier sized ones. I've sealed up most of the cracks and holes and cleaned till I'm blue in the face but every time I flipped on the light there they were. In addition, they left behind (OK - I'm trying to think of a PC term for roach poop) their "droppings" which are absolutely disgusting!!!
So, I decided to go chemical on their a@@. My first attempt was with Ortho Home Defense Max which contains 0.3% Bifenthrin. I went through 2 spray bottles with few visible results.
BUT THEN - I switched to Bayer Advanced Home Pest Control with 0.05% Beta-Cyfluthrin. OMG. This stuff is scary good!!! After my first application (the next morning) I found at least 10 dead ones laying on the floor, plus, a couple more staggering around that I whacked with my broom. Now we're making a dent in the population!!! Since then I've made a few more applications and I finally have the situation under control. Haven't seen one of those suckers in a week.
It has a funky odor and I'm sure it's not a good idea to breath the fumes but this stuff REALLY works great. Be sure to read the label and follow all instructions.
Available at (among other places I'm sure) Home Depot.