Guano piles and staining under the roofline
Bat droppings look like dark, crumbly pellets—often mistaken for mouse droppings until you see how they pile under a ridge vent, porch light, or gable. On Spokane bungalows and Tri-Cities ranch homes, look for streaks on vinyl or brick below soffits and chimneys. Guano can stain siding and accumulate surprisingly fast in a single maternity season.
Ammonia odor and attic air quality
A sharp ammonia smell in the attic or upper floor is a classic colony signal, especially after a hot inland summer day. Urine saturates insulation and wood over months. If you only notice the odor when the HVAC runs or after opening the attic hatch, treat that as a reason for a professional look—not a casual DIY vacuum.
Noises at dusk and grease rub marks
Chirps, squeaks, and light fluttering near the ridge or chimney around sunset track with bats leaving to feed on insects over the Spokane River corridor, Palouse fields, and Columbia Basin. Greasy brown rub marks at fascia gaps, brick weep holes, and vent edges show repeated use of a dime-sized opening.
Watch the roofline at dusk
From a safe outdoor vantage, watch known problem areas for 20–30 minutes after sunset in late spring through early fall. Consistent exits from one soffit or chimney crown usually mean a roost, not a random fly-by. Do not seal openings while bats may still be inside—call for mapping and timed exclusion instead.
Ready for help in Spokane, the Tri-Cities, or elsewhere in the 509? Start with bat removal or an attic inspection.