How do you know if it is blue concrete?

[spikplanka]

that you hire a good inspector yourself and have everything properly checked. Spontaneously, I would avoid buying a house where you can't access crucial parts such as the crawl space.

This is important!

 

[Liljeros]

When we won the bidding, we brought in an inspector who performed a short-term radon measurement (wasn't better then). The values were low, around 20 Bq, and the inspector considered that we could completely dismiss radon as a risk. After a few years, we decided to conduct more extensive measurements at the appropriate time. These showed that certain rooms in the basement had an average of 300 Bq. We then purchased digital radon detectors and began modifying the mechanical ventilation, which made a significant difference, as radon gas is extremely volatile. However, we discovered that certain spaces, like the workshop, had very high values, up to 1000 Bq, due to a leaky well.

After further renovations, we found that a large portion of the lightweight concrete in the basement was actually blue concrete, even though the previous owner assured us otherwise. According to our digital meters, however, the test samples from the walls do not emit any radon.

Radon, especially ground radon, is tricky to handle because it can vary greatly depending on the time of day and season. Additionally, the difference between neighbors can be significant; the neighbor can have 10 Bq while you have 1000 Bq in your house.

Usually, the municipality keeps track of areas with high ground radon, but you still need to measure to be sure if the specific house is affected.

It is often said that radon spreads more easily in dusty environments and is particularly dangerous for smokers. But as with many things, it is not black and white. Even non-smokers can suffer respiratory problems if they spend a long time in environments with high radon levels.

In Sweden, the radon limit is 200 Bq. If you exceed this value, measures should be taken. In Europe, the limit is 100 Bq. Sweden's inability to lower its limit is said to be for economic reasons.

In our case, we have addressed the worst peaks by sealing well covers and improving ventilation. One problem with mechanical exhaust systems is that more ventilation costs more money, especially when it's cold outside. An FTX system would probably solve this, but in our case, the investment is not worth it.

If you are serious about buying the house, I highly recommend that you hire a good inspector yourself and have everything properly checked. Spontaneously, I would avoid buying a house where you cannot access crucial parts such as the crawl space.

It is correct that it is for economic reasons. The majority of cases are related to smoking, which is in strong decline in the country, so it's not inconceivable that it has a significantly larger impact.

The following can be read at
Strålsäkerhetsmyndigheten:
“The Swedish Radiation Safety Authority estimates that approximately 14 percent of lung cancer cases in Sweden are caused by radon. This corresponds to about 500 lung cancer cases per year. 450 of these are caused by radon in combination with smoking, while 50 of the cases are non-smokers.

Lung cancer is the only known health risk with radon. By reducing the radon level in houses with radon values over 200 Bq/m3 to around 100 Bq/m3 or even lower, it is estimated that about 200 lung cancer cases can be avoided annually.”

It can be concluded that reducing from 200 to 100 would almost halve the number of cases, but if people stopped smoking, 90% of cases would instead disappear. Conservatively calculated, extending the lives of about 25 people annually would cost many hundreds of billions.

 

[AG A]

I would never buy a house where it's not possible to inspect the crawl space. It's truly buying a pig in a poke.

As long as there are ventilation vents, it's fine. They are usually enough to see if there are moisture problems, or anything else.

 

[spikplanka]

Another tip is to smell, and if it smells odd, it might be wise to abstain. Especially if you can't inspect visually.

 

[Ironside]

It is correct that it is for economic reasons. Most cases are related to smoking, which is significantly declining in the country, so it's not unlikely that it has a significantly greater impact.

The following can be read on the
Radiation Safety Authority:
"The Radiation Safety Authority estimates that about 14 percent of lung cancer cases in Sweden are caused by radon. This corresponds to approximately 500 lung cancer cases per year. 450 of these are caused by radon in combination with smoking, while 50 of the cases are non-smokers.

Lung cancer is the only known health risk with radon. By lowering the radon level in houses with radon values over 200 Bq/m3 to levels around 100 Bq/m3 or even lower, it is estimated that in the long term, about 200 lung cancer cases per year can be avoided."

It can thus be concluded that a reduction from 200 to 100 would almost halve the number of cases, but if people stopped smoking, 90% of the cases would instead disappear. Gently calculated, this would mean that the lives of 25 people annually could be extended at a cost of many hundreds of billions.

Exactly, that's the case. For those interested in more details, there is a lot to read on the Radiation Safety Authority's website.

Radon is primarily known for its link to lung cancer, and there is no scientific evidence that points to radon causing other respiratory-related problems. Although it's theoretically possible that radon could contribute to less serious respiratory issues, research has so far not found such a connection. As previously mentioned, the risk of developing lung cancer due to radon is relatively low for non-smokers, with about 50 cases per year. However, there might be some underreporting.

 

[BirgitS]

As previously mentioned, the risk of developing lung cancer due to radon is relatively low for non-smokers, with about 50 cases per year.

And a portion of them have probably been exposed to passive smoking, right?

 

[Ironside]

And then some portion of them have been exposed to passive smoking, right?

You can check the statistics.

 

[gaffelriggad]

The first question you should ask is whether there is aerated concrete in the building. If there is no aerated concrete, then there cannot be any blåbetong either. Contact the municipality for drawings and other documents from the building permit. Even a house from the 1960s should have building permit documents. These will show what materials the house was built with.

If the house is manufactured by Ytong and from the 1960s, the risk is extremely high.

 

[Asli]

The first question you should ask is if there is lightweight concrete in the building. If there is no lightweight concrete, then there can't be any blue concrete either. Contact the municipality for drawings and other documents from the building permit. Even a house from the 60s should have building permit documents. These indicate what materials the house was built with.

If the house is of the Ytong brand and from the 60s, the risk is sky high.

There is lightweight concrete in the house according to the realtor's spec.

 

[spikplanka]

Arrange instruments to measure gamma radiation and some way to get insight into the crawl space. If not, it's probably time to make a lowball offer that only covers the price of the plot. Or look at other house properties directly.

Too many indicators suggest that it could become a significant black hole for your money, time, and energy.

 

[Asli]

Arrange instruments to measure gamma radiation and some way to get insight into the crawl space. If not, it might be time to make a low offer that only covers the land's price. Or directly look at other house properties.

Too many indicators suggest it could become a significant black hole for your money, time, and energy.

Your posts plus some crucial practical questions have made us continue with house searching. Very grateful for all the input I've received.