Leaned on a 2x4 in the pool pump shed next to the house last fall and it collapsed under my hand. Totally hollowed out by instects. There is only a PT deck between that & the house. I dumped the Diaz... powder in that hole but have fear of their return both to the shed and the ranch style home. It seems tough to get the powder to stay anywhere outside so I was thinking about using pressure treated wood to create a barrier where shingles hang over the foundation. This house had termites before (came in on the sill) but they were said to have been taken care of. Can I treat the sill from inside or out so to resist entry. Mom notes that long ago they used to spray a tar like solution that lasted forever. Thoughts? Any comments on Dursban (saw notes on webb). PS Last fall I found thousands of the termites/carpenter ants in a pile of marker sticks in the other shed across the yard and sprayed them all dead but fear return. Thoughts on lawn treatment (for carpenter/termites as well? There is no other old wet or dry wood anywhere near the house. I'm surprised that the sheds are not PT. Tx in advance.