On 28/06/15 09:35, Tim Lamb wrote:

The other concern is that the access point is at least 2m from the
nearest outside wall. Floor screed over 50mm polystyrene insulation may
provide a comfortable home:-(

On the odd occasion I find an ant trail in the house, one end gets a
dusting of ant powder which seems to do the job.

Nippon might be helpful as it has always claimed the workers carry it
back to the colony and kill the rest. However, you need to watch to see
if they actually take it or avoid it - some reviews suggest mixing some
sugar in with the liquid works.