We move the coop monitor between in the coop, the run and outside. I am pretty convinced this shows me reliable percent and temp. As a quick check I just lookup online the current humidity in my area and compare it to the current reading of my device. This morning at 9, same humidity and temp.Just use the same device to measure inside and outside the coop.
Note: the chicks had been out of the coop for 4-5 hours when this reading was done.