I live in a detached bungalow. There is a dwarf boundary wall between us and next door. The next door owner has just informed me that he intends to build a PVC type extension on the side of his property which will be either upto or on to the existing boundary wall. Are there any regulations regarding this type of development? My concern is the proximity of the building and any rainwater guttering etc that may end up over hanging my ground. I spoke to a Building Regs., officer and he said they should serve a notice to the effect and allow me time to consider their proposals. How do I approach this without making too much of a problem?