The answer to 'when to replace lighting installation' is that you should replace your home's lighting fixtures and wiring when they show signs of wear, damage, or outdated technology. Typical signs it's time to replace lighting include flickering lights, dimming bulbs, outdated fixtures, or if your home's wiring is more than 20-30 years old.
Replacing old or faulty lighting is important for both safety and energy efficiency. Outdated wiring can be a fire hazard, while newer LED bulbs and fixtures can save you money on your energy bills. It's generally recommended to have a professional electrician evaluate your home's lighting and make any necessary replacements.