carpenter bee repellent

We have a long wing on our house with 2-foot roof overhang supported by poplar wood beams, which carpenter bees seem to love.  We had the exposed wood painted with 2 coats of polyuruthane in 2006, but by spring 2009 the bees were back.  We are going to have the eaves repainted this spring.  Is there a bee poison such as cypermethrin or Drione that can be mixed into polyuruthane that might help to deter the carpenter bees for more lasting protection?

Currently there is no "additive" for paint or stain that can be used to repel carpenter bees outside homes or other structures. There are just too many problems designing such a product and at this time nothing has proven effective for any length of time as the following post explains:

http://www.carpenterbees.com/stain/adding-cypermethrin-to-paint.html

Having dealt with this pest for over 30 years, I'm confident of what does work. For my money and time, the DRIONE DUST applied every spring around the perimeter of my home does the job. It seems as though wasps and bees like nesting where roof and gutters meet by soffits and eaves. These locations notoriously have gaps, a lot of moisture and a protected area (under the eave) which is an instinctive location most bees and wasps try to find when seeking nest sites. Using a DUSTICK, I've learned applying Drione to these areas does a great job of stopping most every insect that might try to invade. And getting it applied in the spring, before pests like carpenter bees establish themselves, seems to be important. As our video's show, the Drione will permeate up into the shingles and gaps and essentially take away these locations as nest sites. And since these are protected from direct weathering, the dust can last several months making for long term protection.

I've also learned most people aren't willing to dust once a year since it does require a little effort and time. That's when we tested and learned the CYPERMETHRIN does a good job when sprayed to these surface areas. Obvisously if you could somehow incorporate the Cypermethrin into the paint you would think you could then extend this residual to last a year or more. But this just isn't the case. If you aren't willing to dust with the Drione, spraying the Cypermethrin once a month will usually do the job. In fact, I'm sure if you applied it every spring to the area you mentioned above you'd be able to stop them before they ever got started. For now, this is the best we have so  I recommend using either of these two treatment regimes and you'll be able to keep carpenter bees and many other invasive pests under control. If you have further questions or concerns, give us a call on our toll free 1-800-877-7290.