I have to remove a telephone extension box and cable. Removing the extension box is no problem, just unscrew it from the wall (it has already been disconected from the BT box). But I need to fill the hole drilled from the exterior of the building that the phone cable comes through. I'm going to do this myself as no doubt BT would charge a small fortune and I'm not rich!
As a novice DIYer, can anyone tell me the best inexpensive way to do this please - what filler to use etc. The filler will be exposed outside at the outer end of the hole.