Seems a mouse had made a home in my exhaust in the week i hadnt burned. Its raining so the son of a bitch was in the exhaust during the daytime. Wife heard it and then i needed to rip the whole exhaust apart to find it. Didnt fimd it, pretty sure it is outsode. And i am soaked. Thing made a whole nest it obviosly knew how to get in and out. But sometimes you just wont win the argument with the wife.
I use this on mine. My outlet has screen, But its still large enough for mice to wonder in. This cap works dandy.
spark arrestor is usually about 1/2"x1/2" squares, so, a bit small for mice.....unfortunately, bees CAN get in! I use a doritos bag and a rubber band! Hard to miss it being there so you dont forget to remove it come Fall.........another thing...if you do have a spark arrestor, dont forget to clean it periodically, whether it is on the sidewall or the roof...they can plug up.
No spark arrestor to my knowledge. I usually remove and wash out my vent round know. It is over my deck and would rether not have it around. Think the grid on the outside is 1" square.
I have a vent stack on the roof- it is off set and narrows down to about an 1" or so at the offset, dang chippers keep filling it up with seeds, they can't get the seeds back out though cause of mesh which I put on due they themselves getting stuck in it. I got three of the little buggers before I came to the shop this morning.