When it comes to replacing a roof, there are several factors that come into play. First and foremost, the age of the roof should be taken into consideration. Generally speaking, an asphalt shingle roof typically lasts around 20-30 years depending on environmental conditions and maintenance. If your roof is nearing its life expectancy due to age – meaning you’ve had it for more than 15 years — then it might be time for a replacement.
In addition to age of your roof, you also need to consider any visible damage or inconsistency seen from either inside or outside the building such as shingles that have fallen off or become loose, dark spots which may indicate water damage, missing flashing pieces around vents and chimneys that could result in potential leaks during rainstorms etc.. Other warning signs include visible sagging or buckling which indicate weakened decking boards underneath; large piles of granules collecting in gutters (this usually means the surface layer of your shingles has been worn away) ; standing water after rainy weather; excessive cracking between shingles; and noticeable sunlight coming through in places where light shouldn’t shine through (like attics). Anytime one notices these issues taking place with their current roof system must take action soon: assess the situation accordingly with a professional inspector before major repairs can no longer happen!