I have two skylights on my roof that I think are original to the house which was built in the 1970s.
There were some signs of water leakage on the wood around the inside on the skylight that the home inspector pointed out to us. We brought these up issues to the sellers who said there had been a leak in the past and that they had been repaired.
We have owned the house for two years and have been through two winters of snow on the roof and many pouring rainstorms and have never seen a leak.
The other day we got over 24 inches of snow in a single storm (which is more than we have ever had). When it began to thaw I saw a minor but consistent leak coming from the ceiling a few feet below the skylight. By the next day it had stopped and we have not seen any leaks since. The snow all melted off and we have already been through another “normal” snow and a heavy rain downpour that lasted for two days. No leaks.
My takeaway from this is that the weight of the extreme amounts of snow opened something up enough for water to get it but that once the weight was relieved the issue abated.
We had a roofer take a look at the issue and he said he could repair the seals as long as we didn't hold him responsible for future issues or we could replace the skylights. I would rather not spend the money to replace them if a repair is all that is needed and I am certainly ok with not holding him responsible.
So, all this background is to ask the question, given that I have experienced no leaks before or since this big snowfall, is it a reasonable decision to just have him repair the issue or is this a clear sign that something more significant will inevitably develop and it would be irresponsible to not take care of it now by fully replacing them.