simon, your house/street /area may have a covenant forbidding it you would need to check your deeds.
In reality what we did and I sugest is suck it and see. If you get any complaints check your deeds if not job done.
If nobody has made a complaint within 1 year of you parking your van there the covenent on that particular part will be nul and void.
I know this as we sold some of our garden as a building plot, got planning permission ext, but the solicitor came up with no infill building on our est. The buyer wanted to go ahead so what he was able to do was get an insurance policy to cover him for 1 year incase anybody complained and the house had to go (cost him a small fortune). Nobody did and the house is still standing, more importantly that covanent is nul and void for our property now.