Question
Now that the beetles have found their way into my home what (besides crushing them) can I use to kill them off?

Answer
I assume you are referring to boxelder bugs. Boxelder bugs, sometimes called maple bugs, are medium size insects about 1/2" long, dark grey with red markings on their back. These otherwise harmless insects can become an extreme nuisance because of their tendency to congregate in large numbers on houses in the fall. If the congregating bugs gain entry to walls or attics they can become a problem all winter as they find their way into living spaces.

In the fall adult bugs leave the maple trees in search of protected places to spend winter months. Large numbers may congregate on trees, and nearby houses, and cause a great deal of concern from affected homeowners. In spring the adults fly off to find maple trees on which to lay eggs to begin the cycle all over again. Eggs are not laid on houses, inside or out

The best way to prevent problems with boxelder bugs is to discourage aggregation in the fall and control bugs that manage to find ways into exterior walls and attics. Homeowners can do these treatments themselves with low toxicity botanical insecticides and dusts

First, exclude boxelder bugs (see What are Boxelder Bugs?) from entering the house by repairing screens and caulking cracks around windows and doors. Bugs that do get in will take up winter residence in wall voids and the attic. They will not cause any structural damage but will become a nuisance throughout the winter. If you are unable to seal exterior cracks you may need to treat wall voids and the attic with insecticidal dust

Second, treat boxelder bugs as they congregate on house siding using one of the three ways outlined below. Bear in mind that bugs become less affected by insecticides later in the fall as their metabolism slows down for winter. Therefore treat as soon as migrating bugs start arriving in early fall.

The most aggressive approach is to apply a light spray of a pyrethroid insecticide to the siding and eves, wherever boxelder bugs congregate. It is not necessary to treat the bugs directly. Pyrethroid insecticides will give longer residual activity but are considerably more toxic and hazardous to apply.