Radon Test Results: 16.4 pCi/l - How to Reduce High Levels?

[russ_watters]

So I got the results of my new townhouse's radon test tonight and it has 16.4 pCi/l - the EPA limit is 4 and the national average is 1.3.

I'm not the panicky type so this doesn't upset me much, but I'm just wondering if anyone has any experience with radon. I figure the current owner can seal the basement walls and add some ventilation and it'll be good, right...?

 

[zoobyshoe]

I think any repairs to be undertaken by the seller have to be stipulated in your bid. Check with a real estate lawyer. Was your bid contigent upon the results of the inspections? Can you get out of it based on this?

 

[rachmaninoff]

No wonder it was for sale.

 

[zoobyshoe]

Radon: element 86, noble gas, atomic weight 222. Weighs more per mole than lead. A weird and interesting element. I wonder what volume 222 grams of it would occupy under normal conditions.

 

[Cyrus]

Who needs birth control when you have Radon. I would check your boys from time to time just to make sure there isn't any shirkage in non-cold weather conditions, if you know what I mean. Kids are annoying anyways, who needs kids?

 

[rachmaninoff]

A weird and interesting element. I wonder what volume 222 grams of it would occupy under normal conditions.

Why, 22.4 litres, of course!

(conversion - 1 mole @STP ~ 22.4 liters)

 

[rachmaninoff]

Russ - is the seller paying for mitigation?

 

[zoobyshoe]

Why, 22.4 litres, of course!

(conversion - 1 mole @STP ~ 22.4 liters)

How'd you figure that? Ejicate me!

 

[Cyrus]

All noble gasses have the same volume at Standard temperature and pressure. (one moles worth of the gas. One mole has the same weight as your atomic number, in this case 222g).

 

[Bystander]

Well, now you know how closely building codes were followed during construction --- radon areas have required perforated plastic pipe under slabs for twenty years or so (not with actual ventilation equipment attached and running, but for use in the event of who knows what). If it's on "hard rock," don't sweat it, you got a lousy test result (walk-out basement trap that much over hard-rock? Uh-uh) If it's on fill, it ain't properly compacted, and it's probably got more in it than just hot stuff.

Actually, there are a couple areas back east that do have fairly "hot" granites, 10s of picos per liter. Didn't think they were around Philly, though. They are known, and if this is one of them, building codes sure as hell required the foundation and slab ventilation system, and if it ain't there, there are other things missing.

 

[zoobyshoe]

All noble gasses have the same volume at Standard temperature and pressure. (one moles worth of the gas. One mole has the same weight as your atomic number, in this case 222g).

Thanks. I did not know they all had the same volume at STP.

 

[RVBuckeye]

So I got the results of my new townhouse's radon test tonight and it has 16.4 pCi/l - the EPA limit is 4 and the national average is 1.3.

I'm not the panicky type so this doesn't upset me much, but I'm just wondering if anyone has any experience with radon. I figure the current owner can seal the basement walls and add some ventilation and it'll be good, right...?

Russ, When I first moved to Omaha, I installed radon mitigation systems. (only for a couple months or so). I wouldn't say I know much about it, but I might be able to answer some of your questions, if it is pertaining to installation.

I can tell you I live in a "Zone 1" area. Highest Potential (greater than 4 pCi/L). Also, I have a sister-in-law who is a real estate agent. After I saw how easy it was to install radon mitigation systems, I thought about adding it as a service of my side business. After talking to her, she told me that even here, radon testing is not a requirement to sell/buy a house. The catch is, once it has been tested, the results have to be disclosed to potential buyers. Her personal opinion was that real estate agents that suggest radon testing, (and then quickly give out the name of a person to install the system once it's found), is an un-ethical business practice. Which I have to say I agree with, and hence I don't offer it. What I find most significant is that radon isn't deemed that much of a threat to be required in the buying/selling process. Maybe we are just behind in the times.

 

[Chi Meson]

The Curies should have never invented that stuff!

 

[BobG]

Russ, When I first moved to Omaha, I installed radon mitigation systems. (only for a couple months or so). I wouldn't say I know much about it, but I might be able to answer some of your questions, if it is pertaining to installation.

I can tell you I live in a "Zone 1" area. Highest Potential (greater than 4 pCi/L). Also, I have a sister-in-law who is a real estate agent. After I saw how easy it was to install radon mitigation systems, I thought about adding it as a service of my side business. After talking to her, she told me that even here, radon testing is not a requirement to sell/buy a house. The catch is, once it has been tested, the results have to be disclosed to potential buyers. Her personal opinion was that real estate agents that suggest radon testing, (and then quickly give out the name of a person to install the system once it's found), is an un-ethical business practice. Which I have to say I agree with, and hence I don't offer it. What I find most significant is that radon isn't deemed that much of a threat to be required in the buying/selling process. Maybe we are just behind in the times.

The EPA says radon is the leading cause of lung cancer among non-smokers: http://www.epa.gov/radon/healthrisks.html

As to what to do, the EPA also has a FAQ about radon and buying/selling houses: http://www.epa.gov/radon/pubs/hmbyguid.html

I guess the seriousness depends on how much trust you put in the EPA's study (which was done by the University of Iowa with help from University of Kansas and St.John's).

 

[Mattara]

So I got the results of my new townhouse's radon test tonight and it has 16.4 pCi/l - the EPA limit is 4 and the national average is 1.3.

I'm not the panicky type so this doesn't upset me much, but I'm just wondering if anyone has any experience with radon. I figure the current owner can seal the basement walls and add some ventilation and it'll be good, right...?

Those levels are extreemly dangerous russ_watters!

 

[RVBuckeye]

I guess the seriousness depends on how much trust you put in the EPA's study (which was done by the University of Iowa with help from University of Kansas and St.John's).

I trust, very much, the EPA's study. I smoke, so I guess I'm screwed anyway.

 

[FredGarvin]

Even if you don't care about the radon levels or can get it remediated, there is the aspect of resale and value that you need to take into account. Russ, I am pretty certain that you plan on getting married and moving out to a bigger place at some point, right? I would seriously consider the fact that you may have a hard time selling that place in the end when you want to move up.

 

[russ_watters]

Well, now you know how closely building codes were followed during construction --- radon areas have required perforated plastic pipe under slabs for twenty years or so (not with actual ventilation equipment attached and running, but for use in the event of who knows what).

It does have the pipe installed and yes, the agreement of sale was contingent on the test (that's why I got the test).

Actually, there are a couple areas back east that do have fairly "hot" granites, 10s of picos per liter. Didn't think they were around Philly, though.

Yeah, southeastern PA is pretty hot. My parents' neighborhood has a number of houses in it that required mitigation.

I guess the seriousness depends on how much trust you put in the EPA's study...

A lot. Enough that after reading the study (I actually found it and read it last night) it changed my opinion somewhat - I had actually thought radon to be a relatively minor risk. Still not something to be too concerned about if it is taken care of properly, but an annoyance.

What I'm actually more worried about is Fred's point - what it does to the value of the house. The appraisal's next week. If mitigation works, there shouldn't be an issue - and I wouldn't much care - but perception is reality and if it scares away potential buyers, then it does have a real impact on the value of the home and ease of sale.

 

[Astronuc]

EPA's Radon Mitigation Standards
http://www.epa.gov/radon/pubs/mitstds.html

Sealing might help, and ventilation seems necessary, and should help.

If the basement is not ventilated now, then the current levels reflect accumulation. It might be worthwhile to ventilate the basement for say a week and then test again.

It seems the house already has the required mitigation systems? They may not be effective if the house/basement has >> 4 pCi/l.

Also, consider FredGarvin's comments.

 

[RVBuckeye]

It does have the pipe installed and yes, the agreement of sale was contingent on the test (that's why I got the test).

Are you talking about "drain tile" here? Which is the perforated pipe that is under the slab and drains into a pit in the basement, where the sump pump is. Do you have a sump pump or even a basement? The reason why I ask is this is a good starting point on how how much radon is getting into the house in the first place. (When installing, the perferred method was utilizing the existing drain tile, by covering the sump pit and using this as the suction point.)

What I'm actually more worried about is Fred's point - what it does to the value of the house. The appraisal's next week. If mitigation works, there shouldn't be an issue - and I wouldn't much care - but perception is reality and if it scares away potential buyers, then it does have a real impact on the value of the home and ease of sale.

I think here it's a double-edge sword. A potential buyer could be turned off by the un-asthetic quality of having a 4" pipe running up through the house. Here I state that that most housing designs don't have many points in the house where you can route it without going into "living spaces". The places that are the best are usually already occupied by plumbing vents. Then the other alternative is running it out the side of the house and up past the roofline. Un-appealing as well.

 

[Moonbear]

I'm actually more puzzled as to how you're getting that high of radon levels accumulating in a walk-out basement.

Yes, resale is the big issue here, as well as living in the place if mitigation doesn't work. Think about it...you're a well-educated person, knowledgeable in science, and not prone to overreacting to things, and it's even giving you pause before buying the house; how will someone who hears the word "radiation" and thinks all their children will be born glowing green perceive such a purchase? Plus, the appeal of a walk-out basement is that you'll actually use the basement for entertaining, not just a storage space, and if the radon levels get that high there, then you're not going to want to use it.

Since this is a "starter" home for you, and one you'd want to move up and out of eventually, maybe sooner than later even, I think you need to give serious consideration to the challenge this is going to present for resale.

I know that once you get your heart set on buying a home, it's really tough to walk out of the deal, but you'll find another one, and it's better than being stuck with a home you can't resell when you're at a stage of your life when you know this is just a "first" home, not the one you're going to grow old and raise a family in.

 

[Bystander]

Quick question: is that neck of the woods still oil heating country? Or, have gas prices dropped enough to get "clean" furnaces into new construction?

Reason I ask, "large" amounts of Rn move in gas lines, enough so that it is occasionally necessary to handle old compressors as rad waste, single digit number for total number of incidents I've heard about. Test should have involved multiple charcoal collectors; if one was closer to water heater, or gas-fired furnace, and showing a higher count, mystery is solved. Resale value has still taken a bite, but the "problem" can be explained.

Levels that high in a walk-out basement via diffusion, migration along grain boundaries, through the foundation-slab gap? Sumpin's a little odd.

 

[Moonbear]

Quick question: is that neck of the woods still oil heating country? Or, have gas prices dropped enough to get "clean" furnaces into new construction?

Reason I ask, "large" amounts of Rn move in gas lines, enough so that it is occasionally necessary to handle old compressors as rad waste, single digit number for total number of incidents I've heard about. Test should have involved multiple charcoal collectors; if one was closer to water heater, or gas-fired furnace, and showing a higher count, mystery is solved. Resale value has still taken a bite, but the "problem" can be explained.

Levels that high in a walk-out basement via diffusion, migration along grain boundaries, through the foundation-slab gap? Sumpin's a little odd.

Hmmm...Russ, the company that did the testing...do they also do mitigation work? I'm wondering if there's any potential conflict of interest to report the one anomolous, likely false-positive, reading over all the non-detectable readings, for example.

If you really like this place, it might be worthwhile getting a second radon inspection from another independent company. See if they get the same results. In terms of resale, and in terms of the cost of the house, consider the added expense that you'll want regular monitoring being done for two reasons: 1) if there really is radon at that high of levels, you want to be monitoring for your own health to ensure any mitigation is working or to know to do more, and 2) for resale, if you can show that although when you moved in there was a high reading, with continuous monitoring over the duration of your residence there, that was shown to be an anomalous reading and it's been low ever since, then that will help ease concerns any next buyer might have.

 

[russ_watters]

There were two tests in the basement - 16.4 and 16.3. The first floor also got tested at 7.9. The place is only 2 years old, so accumulation is unlikely. The heat is propane - via a neighborhood-wide distribution from a tank.

Yes, the basement has a sump pump, and I assume that's how the mitigation will be done, but I'm not really sure. I need to get more info from my realtor and the seller, plus I'm still trying to educate myself on this issue.

Thanks for all the replies, everyone.

 

[Moonbear]

Yes, the basement has a sump pump...

I might be pickier than other people, but when I was shopping for houses, if I saw a sump pump, I immediately checked it off my list. My reasoning is that people don't install sump pumps unless they're needed. And it means the basement doesn't just get a little trickle of water that you might be able to seal up, but that there's enough seepage to create a small pond during a rainstorm. While the sump pump theoretically will keep the water from accumulating (depending on whether it can keep up with the amount of water coming in), it still means a substantial amount of water gets in and the basement will be damp so you can't finish it or put much in it without raising it all up off the floor.

 

[Bystander]

Half-life is four days; month gets you to "equilibrium" with Ra in a "closed" system. Couple months should clean LP far as any hitchhikers, and it gets that in transport and storage.

You are looking at a structure that is located over: 1) fairly mobile ground water in fractured "hot" rock; 2) loose fill covering a truckload of radium painted aircraft instrument dials from WW II, or something similarly savory; 3) a major ore body.

I'm inclined to think "2)." Fill that "breathes" well enough to move that much radon isn't the place to be sitting next time Hurricane Agnes comes through. Been years since I've been back that way, but I don't remember a whole lot of Jurassic outcrops above the "fall zone;" doesn't mean there aren't any, and doesn't mean some of the glacial till in valley floors ain't ground up Jurassic "hot stuff." Should be a "Soil Report" with the rest of the real estate paperwork on the property, that is a "swelling clay" area --- I know a garage slab in Wilmington that had an 8" heave summer to winter. Whether it'll give you an original surface profile and finished grade specifications is another question.

 

[scott1]

Did the seller worn you about?You might be able to get them to pay to get the radon removed

 

[Akis]

i'm writting this message in response to your question about radon. all the walls emit radon, but by freshing the atmosphaire of your house, you'll be able to lessen the numbers of radon. you can do this by opening your windows many times per day. In other worlds let the sun get in your house..

 

[russ_watters]

I might be pickier than other people, but when I was shopping for houses, if I saw a sump pump, I immediately checked it off my list. My reasoning is that people don't install sump pumps unless they're needed. And it means the basement doesn't just get a little trickle of water that you might be able to seal up, but that there's enough seepage to create a small pond during a rainstorm. While the sump pump theoretically will keep the water from accumulating (depending on whether it can keep up with the amount of water coming in), it still means a substantial amount of water gets in and the basement will be damp so you can't finish it or put much in it without raising it all up off the floor.

I'm reasonably certain it's the law in PA that every basement needs a sump pump. I've never seen a basement without one. In the disclosure statement, it says the sump pump has never run, and being on the side of a hill, I can't imagine it ever would.

One thing about the economics - PA is pretty hot (there is a large gelogical deposit of uranium, stretching from the middle of PA, through north Jersey, and into New York): something like half of all houses in southeastern PA have a radon problem, and because it is that common, it may not have that much of an impact on the economics.

 

[Evo]

I'm reasonably certain it's the law in PA that every basement needs a sump pump. I've never seen a basement without one. In the disclosure statement, it says the sump pump has never run, and being on the side of a hill, I can't imagine it ever would.

I've never seen a basement without a sump pump, if water gets in your basement, you want it proactively removed to prevent flooding.

I'm sorry to hear about this snag with your new home, better you found out before you purchased so you can make an informed decision.

 

[RVBuckeye]

I, for one, wouldn't really let it influence my decision of whether to buy the house or not. If it is the asthetics thing, the sump pump is usually in a closet, in a finished basement, and if not, it's already an eyesore anyway. Running it out of the pit, out the side of the house, and up the exterior of the wall can be done in such a way that it blends in. I used to run it from the pump to the wall, up to the 2nd floor joists (above grade), out the side. Once outside, mount the fan (which cuts down on the constant humming of the motor, what little there actually is). On top of the fan you can put an adapter that changes from a 4" round pipe to a rectangular shape. (I forget the technical name but any hardware store should have it in their gutter section). I then ran aluminum gutter (or plastic) up along the exterior of the home, above the roofline. The nice part about this method is the downspouts can be painted to match the exerior house color and it looks 100x's better than fat PVC pipe running up the side of your house. That, I believe is a little innovation that was a big selling point. Might want to mention that if looks is a concern.
It's cheap, (can even be done as a DIY project), and I could do it in 2-3 hours, if coming out of a pit. Now if you have crawl spaces, which I doubt in a townhouse, that's a different story.
Often, even in houses with this level of radon, mitigation can be done with one suction point, without sealing every nook and cranny in your slab and walls.
I would hate for you to pass up a house you love, for something as simple a fix as this one. Hope this helps. Good luck.

 

[Moonbear]

I've never seen a basement without a sump pump, if water gets in your basement, you want it proactively removed to prevent flooding.

Really? I've only seen sump pumps in wet basements...they're installed usually after the first flooded basement. If you don't need it, why would you want a gaping hole in the floor in the basement? Water shouldn't get in in the first place, so if they're putting in a sump pump, that says to me someone had reason to think water could get in. I've never lived in a house with a sump pump, and never needed one. Of all my friends and relatives, I only had one great-aunt who had a sump pump, and she definitely needed it. Her house was around 100 years old when I was a kid and definitely had a leaky basement that flooded when it rained (stone foundation...those almost always get moisture in even the best of cases). When I was looking at houses, you could just tell that the basements with sump pumps got water in them...they all smelled really musty. It was tough finding a house that didn't need one though in Cincinnati...the soil there has a lot of clay that doesn't drain well, so during hard rains, a lot of the houses are practically sitting in a bowl of water around the foundation. But where I grew up, the soil was very sandy and drainage was never a problem unless you lived at the bottom of a hill and got all the run-off, so nobody had sump pumps, and it was really rare for anyone to have even a damp basement let alone a flooded basement.

Russ, in the area you're looking, is there a similar issue of the ground being of a type that many homes are prone to flooded basements that they'd install them in every home just assuming they'll flood at some point? Maybe because they're building on rock? I don't know anyone who bought a home in Philly; most everyone I know bought on the Jersey side and commutes/commuted to Philly.

 

[Evo]

All of the homes built within the last 20 years that I've been in had sump pumps already built in. The only homes I haven't seen them in were older homes.

 

[RVBuckeye]

I guess it depends on local regulations, and I can only speak for here, any new house with a basement is required to have drain tile around the foundation which flows into the sump pit. Whether or not an actual pump is installed, is dependant on whether, during construction, water collects in the pit. If it stayed dry, a pump wasn't installed. Better safe than sorry. If water starts coming up through the slab, post-construction, you can't always just dig a pit and call it good. It usually turns into a very expensive, labor intensive undertaking. (sorry to keep popping in here with these "nuggets", but we did this too).

 

[Moonbear]

I guess it depends on local regulations, and I can only speak for here, any new house with a basement is required to have drain tile around the foundation which flows into the sump pit. Whether or not an actual pump is installed, is dependant on whether, during construction, water collects in the pit. If it stayed dry, a pump wasn't installed. Better safe than sorry. If water starts coming up through the slab, post-construction, you can't always just dig a pit and call it good. It usually turns into a very expensive, labor intensive undertaking. (sorry to keep popping in here with these "nuggets", but we did this too).

But that's my point. If water is coming in even during the construction, I wouldn't want that house. Why would anyone buy a house that they can't even keep dry when it's brand new?