Replies

1. Expert Member
   Michael Maines | Dec 04, 2023 02:09pm | #1

   This guide should answer your questions: https://www.epa.gov/sites/default/files/2014-08/documents/buildradonout.pdf

1. 
   Ryan_SLC | Dec 04, 2023 02:20pm | #2

   You're awesome. Thanks for all your help!

2. 
   Ryan_SLC | Dec 04, 2023 02:24pm | #3

   I was going to say it didn't detail the hole, but it does. Thanks again!

3. 
   Ryan_SLC | Dec 04, 2023 02:37pm | #4

   I lied again. It doesn't describe the hole. No size, depth, or circumference.

   Just says "one inch below the concrete slab. So this rookie still doesn't know if that's sufficient or if you should dig down or not.

1. Expert Member
   Michael Maines | Dec 04, 2023 03:04pm | #5

   I don't have direct experience with retrofits, which it sounds like is what you're doing? I'm not a radon expert; companies exist that specialize in that and they might be worth hiring.

   The retrofit systems I have seen use an existing sump pit or floor drain. If your home is not too old, you might have luck digging your own hole; the depth would be whatever gets you past a gas-permeable layer--usually sand or crushed stone. Ideally there would be a plastic vapor retarder below the slab as well. If you can get to that layer, you can install a Tee fitting as shown, and there's no reason the hole would need to be wider than what you need to install that fitting. If space it tight you might be ok with just a straight pipe but the Tee fitting provides more intake area. The guide recommends a 3" or preferably a 4" solid riser to exit near the ridge of your roof.

1. 
   Ryan_SLC | Dec 04, 2023 04:24pm | #6

   Yeah. It will be retro. Considering how cheap everything appears to be built on the house, I doubt poly was put under.

   I think your kinda answer thing. The retro hole itself doesn't need to be like a massive hole or somehow wider to pool the radon to them be sucked out.

   I've got a hammer drill and the rest seems pretty straightforward So that's why I'm thinking not having a company do it. It's like the whole yard pvc sprinkler system, just air not water, in the air and not the ground, and connected to real power not low voltage. Just like a sprinkler system :D

1. 
   Joe_in_Colorado | Dec 04, 2023 05:09pm | #7

   When we hired a company to do a retro they just broke through the concrete and lo and behold due to all the settling of the soil over the years (45 yr old house) there was several inches of air space between the bottom of the concrete and the top of soil under the slab. That was all it took to get the levels down from 9-10 to less than 2. Good luck!

1. 
   Ryan_SLC | Dec 04, 2023 05:13pm | #8

   Thanks Joe!

   I moved a toilet sub out in our basement had the same experience with a big gap to the dirt. Okay then. Maybe it's not like I need to dig a well.

   Perfect