Modern rooflights can be very long lasting, giving their best for 20 years or more in many cases. If you have older rooflight though, they might not be as advanced and will probably need to be replaced after a few years. There are some tell-tale signs you can look out for to see if your rooflight might need to be replaced.
First of all, the most noticeable visual sign is condensation. If the seal is broken or the glazing is old, the rooflight might begin to get condensation forming on it. If this happens when it didn’t used to, there is definitely cause for concern.
The next thing you might notice is a drop in temperature. This can be quite distinct and can make a room uncomfortable. If you have an older rooflight that is letting in a draught or has cold spots around it, you should consider a new rooflight with better u-values.