adam maiden
That would be totally up to your self to decide 20-25 year old felt roof is a very good age as thay normally only last around 10-15 years personally I would wait for a leak but if you are planning on decorating in the room where the flat roof is I would change the roof first to a rubber roof as the life expectancy is 50 years for a rubber roof little more expensive but well worth the money as long as you use a trusted rubber roofer if you was to get a rubber roof make sure you get minimum 10 years guarantee hope my advice is helpful best regards worcestershireroofing.co.uk
