Why do roof repairs cluster in the wet season?
Because the wet season tests every joint on the roof, and the long dry summer hides the failures. Moss, trapped needles and wind-lifted edges do not leak in August. From late October they meet daily rain, and November, the wettest month at Concrete, finds whatever was already weak.
Climate tables for Concrete put annual precipitation at roughly 70 to 75 inches, with winter highs around 42 degrees Fahrenheit. A roof in that climate does not dry out between storms for weeks at a time, so a joint that wicks a little water in October is a stain on the ceiling by December.
The practical lesson is to look before the rains. A walk around the house with a pair of binoculars in September finds curled shingles and clogged valleys while the roof is dry and a repair can be done in good conditions.
Can a roof leak be fixed without replacing the roof?
Often yes. If the covering is still sound and the leak comes from flashing, a valley, a vent boot or a few damaged shingles, a targeted repair can solve it. If the shingles are brittle across a slope, a patch will not hold, and replacement is the more honest advice.
Ask the roofer to explain how they ruled out other causes. A good answer mentions the attic: stained sheathing, damp insulation and where along a rafter the staining begins. A poor answer is a bucket of sealant applied from the ladder.
If a repair is likely to be temporary, ask for that to be said in writing. The page on roof leak repair covers how leaks are traced, and roof replacement covers what happens when a patch is no longer enough.
Does moss mean the roof needs repair?
Not by itself. Moss holds water and debris against shingles and can lift tabs, but it can also be removed and kept in check. If the moss has lifted shingles or packed a valley, the lifted parts need repair as well as cleaning. Oregon State University Extension advises against pressure washing shingles.
Moss thrives in this valley because of shade and constant damp. Removing it does not repair what it has damaged, and aggressive cleaning can strip granules from the shingles. Read roof moss removal and prevention for what treatment involves and what to avoid.
What should be checked after a windstorm or a falling limb?
From the ground, look for missing or folded shingles, bent flashing, damaged gutters and any limb resting on the roof. Inside, check the ceilings and the attic for new stains or daylight. Photograph everything before it is moved. Do not climb up to look.
Atmospheric-river storms bring wind and sodden ground, which is when shallow-rooted conifers come down. A limb that has landed on the roof may be holding a hole shut, so a roofer should decide how it comes off. See storm and wind damage repair and fallen tree roof damage if the damage is more than a few shingles.
What should you tell the roofer before the visit?
Give the town, the age of the house, the roof material, where water shows inside and when it began. Mention any earlier repairs, any trees overhanging the roof, and how the driveway and gate look. These details let the roofer bring the right materials and plan the trip up the valley.
A short list helps. Write down the room, the date you first saw the stain, whether it grows after rain or after snow melts, and what you have already tried. Photographs from the yard and from the attic hatch, taken in daylight, tell the roofer more than any description.
Also say what is on the property besides the house. A shop with a lifted ridge cap or a shed with a loose panel is often an easy fix on the same trip, and in a place where a visit may mean an hour of driving each way, combining small jobs is sensible for everyone.