I bought a house in the hills of Los Angeles and we tested for radon. Turned out it was very high, and LA is one of the few places in California that has high radon. We got it mitigated, and it wasn't that expensive. I talked to neighbors and real estate agents, and no one wanted to know anything about it. I was shocked. Everyone is pulling the wool over their own eyes here.
Do you have a source for the high radon in LA? According to this county source it is pretty low in LA county but much more pronounced in Ventura county (1% homes with high levels vs 14%). I imagine there is some potential for accumulation effects but this is probably much worse in markets where the homes actually have basements.
I found a map at some point. It was 5 years ago. I'm in the San Fernando valley area myself. I do believe there were hotspots in the hills here but perhaps it was mostly ventura county. I'd have to find the map.
Drill a 6” hole through the concrete foundation and dig out about 15-20 gallons worth of material. Install a 3-4” PVC pipe into the hole (the end of the pipe should be a few inches below the bottom of the foundation) and seal the hole up with hydraulic cement. Continue the PVC pipe up out out of the house. There are lots of rules around distance of the outlet from windows and doors and how high above roof line. Inline install a radon fan. How big a fan you need depends on many factors like soil type, home dimensions, etc. The fan runs 24/7 creating a vacuum under the house.
Yes. I went into detail in another message in this thread. I neglected to mention that our garage is a slab foundation unlike the rest of the house so it involved drilling a hole and putting in a ventilation pipe into it, as others have mentioned.
I’m actually scheduled for an install next Monday. Mine has two components:
1. The ventilation isn’t really “in the house” - the fan pulls from below the slab (and exhausts outside) to prevent radon seeping through.
2. Based on the best guess about my home age/area and radon patterns in my house, the slab was probably poured around the furnace, so the mitigation will include disassembling/reassembling my furnace to seal underneath.
