Patios
For paving your driveway, new rules have come into effect which you need to be aware of. For back patios however, there's no restriction of the area of land which you can cover with hard surfaces.
However, if you're planning to have works done for embanking or terracing to support a hard surface you may need a planning application for this.
If you live in a listed building, check with your Local Planning Authority to see if you need listed building consent.
Source planningportal.gov.uk