Radon

[Prometeo]

Good day everyone,
I open this discussion for suggestions on what are the best settings to avoid Radon.
70s house,
3 floors,
old windows.
The basement was 3.60 meters high
starting from the ground,
and a ventilated crawl space was created (vents communicating with the outside) over the entire surface, except the under-stairs area, where I only have a reinforced concrete slab
to have the space
to stay standing,
therefore without a crawl space.
I have a door in this under stairs
and a small window,
how is it better that window
open or closed?
OAK or not?
I think some people say to pressurize the house,
instead of depressurizing,
I'm very confused at the moment,
some say that Radon can also develop on the upper floors,
I welcome advice, thanks in advance.

 

[EatenByLimestone]

Do you know if you have a radon issue? I’d test that first before figuring out the best mitigation strategy.

 

[ABMax24]

As per above, test to see if you even have a Radon issue. Every house is different.

 

[EbS-P]

Radon is heavier than air and water soluble. It’s is a stable isotope of the U238 decay chain. It has a relatively short halftime. About 4 days.

Basements are generally not sealed that well and not ventilated well and due the stack effect low pressure zones. All of this means radon collects to its highest concentration in basements. I would find it very odd to have radon on upper stories. With one exception. The houses water source has very high concentrations of radon and the upper stories are where all bathing and washing takes pace in a poorly ventilated space.

 

[begreen]

Is radon commonly an issue in the region?

 

[Prometeo]

@EatenByLimestone
@ABMax24
I agree, I haven't measured yet, I'm considering the right tool


@EbS-P
Thanks for information, I have to investigate, appears to be very toxic. I read some reviews on Amazon, high values in the bedroom, it seems that it also depends on some materials.

@begreen
Nobody here seems to talk about these things, I checked some national data, this region is not indicated as risky, but..

Basically, I had a communication hole between the under stairs and the crawl space, I thought it could work as a vacuum cleaner, but the opposite the whole crawlspace, blew, with force, inside the house,
through that hole
There was a strange time, I think the stove sucked in a lot of that air and brought it further into the house. now that hole has been redirected outside, I no longer have communications with the ventilated crawl space, but I still want to have the right technique, to avoid this danger

 

[begreen]

Test. For some areas it is not an issue. See if there is a map of radon areas in Northern Italy.

 

[Rusty18]

Get a decent electronic testing device. I got one of the rd200 RadonEye units on Amazon. Supposedly has same sensor as their high end unit just no cal certification. It will definitely give you a relative reading so you can see how different conditions affect radon level. For me, I had a jacked up hvac system that was putting a lot of vacuum on my crawl space. Made some changes and readings dropped to almost zero in the cs and to zero in the house.

 

[peakbagger]

If you are in area with granite and deep wells drilled into granite there is good chance you have radon. If there is no ledge in the area, its rare or radon to be an issue. KIts are cheap, just buy them from a hardware store, set them out in the living space for the number of days the kit says to and then send it back to the lab and they will send you the results. To test for radon in water, you buy a kit, follow the directions to take a sample and then send it to the lab who sold the kit.

 

[Prometeo]

@begreen
this area is classified as medium, i.e. 40-60 bq per cubic meter, the soil is not porous, but very clayey, I don't know, what I know, I didn't like that air
coming from the crawl space

@Rusty18
I followed your advice and bought exactly that, I was undecided with another, portable, but it seems that these devices have to stay hours, in the same place, and therefore opted for this, thanks

@peakbagger
technically granite no, but tuff, it's quite common, I opted for a digital detector, at this point I also want to check on my family members

 

[EatenByLimestone]

I’m in the process of selling a house. After the inspection I was doing some work in the house and came upon these. They set them out, close them up, and mail them out in the envelope you can see in the corner.

 

[Rusty18]

@begreen
this area is classified as medium, i.e. 40-60 bq per cubic meter, the soil is not porous, but very clayey, I don't know, what I know, I didn't like that air
coming from the crawl space

@Rusty18
I followed your advice and bought exactly that, I was undecided with another, portable, but it seems that these devices have to stay hours, in the same place, and therefore opted for this, thanks

@peakbagger
technically granite no, but tuff, it's quite common, I opted for a digital detector, at this point I also want to check on my family members

Yep, it will take about an hour to get your first reading then it will update every 20 mins or so. I’m happy with mine and was able to test different spots in the house (bedroom, basement, crawl space) at different times of the year. The app lets you trend readings back to see what the levels have been since the last time it was reset.

 

[Prometeo]

@EatenByLimestone
They appear ready to ship !
Yes, there are these services in Italy too, but I preferred a faster system, to independently make more measurements in less time

@Rusty18
Very good. I imagine you added an external socket to the hvac and you solved the problem?

 

[Rusty18]

I did not. My supply duct work in the crawl space is bad, the return is atrocious. I started to patch all of the cobbled up joints and realized I just needed to rip everything out and start over. Fast forward nobody wanting to touch duct work unless I bought a whole new hvac system from them I popped the return trunk line apart in the basement and blocked off everything piped in through the crawl space and rerouted all of my return air through two big vents in the living room (directly above the air handler). System still not fixed but when I quite pulling all of the vacuum on the crawl space radon issues went away.

A slightly annoying but not unforeseen side effect of doing that was you don’t ever want to go to sleep with a bedroom door open about 3”…that air handler will slam it shut! I just make it a point to leave all the bedroom doors about half open and the air gets where it needs to go. I have ductwork replacement on my list to do this fall/winter.

 

[Prometeo]

@Rusty18
Thanks for information, I'm happy that even though you have work to do, you still solved the problem. Yes, I can imagine it without losses, with pressure / depressure doors that can close independently.
Some strange stories will be born in this way 😀 lol