Im extending an existing brick garage by five feet in two directions but im very close to the main house. Is there a law on how far the garage should be from the house and do i need planing and building regulations
You may be able use your Permitted Development Rights, and hence not need PP, but rather than try and explain the complex rules it's better to do as the above suggests - they don't bite.
You wouldn't need Building Regs approval unless the footprint of the new garage (measured externally) is more than 30 square metres in area.