Building regulations approval is not generally required for landscaping but beware that if you are removing large amounts of earth you may need to build a retaining wall and will need to talk to a structural engineer.
If you are landscaping near your home make sure your soil levels are low enough to not transmit damp to your property (two courses i.e. layers of brick or stone) below the damp course and don’t block off any air vents.
Generally a new driveway or patio area doesn't require building regulations approval but you must make sure that any alterations do not make access to the dwelling any less satisfactory than it was before.
So, for example, changing levels to introduce steps where none existed before would be a contravention of the regulations. If your home has an external level threshold to a room or a ramp you must retain that.
Building regulations for decking
If your decking needs planning permission then building regulations will also apply and you'll need to consider things like:
- the structure and stability
- the size of joists and whether they're fixed firmly
- any steps required
- how you will use suitable guarding to prevent people from falling off the edge