On Mon, 28 Jan 2013 06:58:04 -0500, George
wrote:

Our radon outlet pipe ends in a down-facing elbow, above the 2nd story
roof. When I installed it, I put a screen over the outlet, thinking to
prevent bugs and birds from nesting. In recent bad weather, the screen
got plugged with snow, stopping the discharge. I pulled the screen off.
Now, I'm wondering whether a screen is necessary. The airflow is fairly
strong, and cool in the summer, which I think would discourage bugs.
Birds, ... who knows?

If anyone has experience in these matters, I'd appreciate hearing.

No experience with radon mitigation pipes-- but I know Mr. Murphy and
his law all too well.g

Sure as heck, as soon as that screen comes off, the fan dies and
critters start lining up to get into your basement.

I would use 1/4" hardware cloth as a fair compromise between critters
I could handle in the basement and allowing a free flow of air.

I just had a thought-- how did snow block it? Presumably there is a
fan blowing air that is likely at *least* 25 degrees above freezing.
Am I mistaken in thinking that those radon fans blow continuously?
If your basement is colder than that- you might want to address *that*
problem.

Jim