Ceiling leak and water stain
Stains, bulges and damp patches inside
Underlayment is the layer between decking and covering, and it is the roof's second line of defence — the thing that keeps water out when wind drives rain under a shingle course. Felt becomes brittle and tears; synthetic lasts longer but still degrades where it has been exposed. It is only accessible when the covering is off, so it is replaced during a re-cover or a large repair rather than on its own, and skipping it to save money removes the backup entirely.
McLean County gets the full range — freeze-thaw cycling through winter, severe convective storms with hail and straight-line wind in spring and summer, and enough temperature swing between them to work every joint on the roof loose. Freeze-thaw is the quiet one: water finds a hairline gap in flashing, freezes overnight, expands, and opens it slightly wider, repeating through a McLean County winter until a joint that was watertight in October is leaking by March. Spring brings the loud damage, and derechos have put straight-line wind through this region at speeds that take ridge caps and whole shingle courses. Housing stock here is older than average, which means a lot of roofs where the flashing has already been through several decades of that cycle.
It is the only thing between wind-driven rain and your decking once water gets under a shingle course — which happens on every roof in a hard storm. Omitting it is why some roofs leak despite looking perfect from outside.
Synthetic is lighter, tears less, and tolerates exposure far better if the job runs over several days. Felt is cheaper and perfectly adequate when covered promptly. On a steep or exposed roof, synthetic is worth the difference.
Stains, bulges and damp patches inside
Cracked rubber collars around pipes
Where two roof slopes meet
Keeping debris out of the gutter
Algae streaking and moss growth
Scheduled checks instead of emergencies
You will get a straight answer on whether McLean County needs someone out today or whether it can wait — before anyone quotes you for anything.
Call (706) 696-1888