[Cob] re: ants??

[Robert Matthews]

Hi Tys and all
I am planning a cob house in an area considered by some, due to the
enormous number of ants, to be a very large ant hill.  It's actually a
mountain range, the Sierra Nevada,  in Spain. Nevertheless the ant
problem does worry me as every house I have been in around here has ants
in the summer. These houses are of a more conventional or traditional
build - including stone/mud or brick/cement - yet they all fail to keep
the ants out. We don't mind the odd family coming to stay in the summer
- it has its bonuses but I don't want them making huge colonies in the
walls and causing the house to fall down. 
If anyone has experience of building an ant ridden area do speak up. 
Many thanks
Robert