so i had the same issues as tillywiz. nov,20 dec20 still going on jan 21.
im literally so gutted as this has been going on for about 3 years now.
my roofer ( meant to be a friend ) did the job for he is a roofer and has a company etc.
he put fibreglass roof but when it happen last year he came back to add another top coat.
it happened again and i managed to get him back again another top coat was put on.
now 28th dec 2020 im an the end of knowing what to do. i called him he came back and put touch on felt.
seems likes its got worse ( maybe because the felt i snot wrapped around the edges of the roof ? maybe because he scrapped away fibreglass particles ?
i have no idea. it was never this bad last year. only ever haves in november / december time.
could this really be an install issue or the way he has boarded the roof ?
between the top coats he never scrapped much away just brushed loose flakes of topcoat, never sanded, never fibreglassed its....
maybe teh boards were not bandaged proper or at all ?
any suggestions and any local companies that can actually fix this ( even if that means a new roof ) or a pitch roof instead ? and totally throw away the lantern ?