" wrote:
On Jan 28, 7:02 pm, wrote:
On Mon, 28 Jan 2013 10:47:04 -0800 (PST), "





wrote:
On Jan 28, 8:39 am, wrote:
On Mon, 28 Jan 2013 07:22:34 -0500, Jim Elbrecht
wrote:

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.

They don't take air from your basement, rather from under the slab. If
a critter were to crawl down one, they wouldn't end up in the basement
(see: sentence #1). There isn't a lot of air coming out of these
(see: sentence #1).- Hide quoted text -

- Show quoted text -

But there is always some leakage from the basement into the radon
exhaust system, and that means there is some place some small size
critters could get into the house proper.

There shouldn't be any such leakage. Nope, not if it's installed by
anyone with more than a single-digit IQ. The pipe should be
completely sealed from above the roof to below the slab. The system
won't work if there are leaks. The whole idea is to pull a partial
vacuum under the slab.- Hide quoted text -

- Show quoted text -

If the OP has a fairly strong air flow as stated, I would bet my
pension there are some leaks somewhere. Radon just doesn't come out
of the ground that readily. The vacuum sucks air into the system
from all the cracks around the basement floor and walls, bringing any
radon oozing thru the dirt along with it. If there were no leaks in
the foundation anywhere, there would be no way for the radon to get
into the basement, it would just flow around the foundation and work
its way into the atmosphere all around the sides of the basement, and
the OP wouldn't need an abatement system.

Strong flow might mean anything. Radon leaks through cement, even if there
are no visible cracks. The amount of airflow is also dependent on how much
free area there is around intake. A large pit of large rocks can pull a
bunch of air. If soil is water saturated, flow will decrease.

Greg