Works of a minor nature to your home may not require a building permit. A new kitchen, replacing an existing window (like for like), upgrading the bathroom generally do not require a building permit. However, be aware that plumbing and electrical work still need to be carried out by qualified and registered tradesmen.
Where your internal home renovations require structural changes such as removal of load bearing walls, or installing a wall, underpinning or replacement of footings, increasing the floor area or height of the building…. a building permit must be obtained.
If you are uncertain about the need for a building permit, it is best to seek advice from EGBP before you start your renovation works.