If you're planning to build any sort of fence, it is always wise to consult your neighbours before you start work. On certain sites, you may also need to consult your local authority's Building Control Department for permission, as there are certain planning rules that govern the size and appearance of constructions and their effect on adjoining paths and neighbouring gardens.

Fences (or any other structures) that form a boundary with a road must conform to building regulations, especially with regard to safety - planning permission may need to be granted.