Sills from after 1978, problem?

[maja.andersson27189]

normally you have something to stop the moisture between the concrete and the sill,

Absolutely, but rarely in the 70s (and sometimes early 80s) unfortunately.

 

[kallekarwe]

That's somewhat true. An uninsulated concrete slab is indeed on 100% moisture, and this moisture migrates through the slab up to the sill plates. In wood. That stands directly on it. But it's not impossible to fix. I've personally purchased two slab houses 100% knowingly, but I also budgeted for sill replacement and the installation of ventilated floors. The problem is more when you buy a house with this type of construction without expecting to need to take action - but then feel the need for action due to odor, for example, and then become sad because it’s quite costly to fix but you are the person who has to do it (not the insurance, not the previous owner)...

Yes, I understand and agree. It's about being aware of the risk. But it's hard to know how big the risk is. If you budget for everything that can go wrong with a house also going wrong, you'll probably never win a bidding.

 

[kallekarwe]

Of course, there doesn't need to be a problem with the construction of concrete slab and baseplates. It depends on things like drainage and runoff…..
If you buy a house where a moisture measurement doesn’t show any problems, that’s probably the case. If the house has stood for 45 years without any problems, it’s unlikely issues will suddenly arise - unless you or someone else does something that affects the surface water.
I live in an area with houses, all built in 76-78. Slab on grade + baseplates. Some have replaced baseplates, others have not. No one has had major problems, but there might be moisture in certain baseplates. My personal experience is that where people have had flowerbeds or bushes next to the house for 45 years, there might be moisture in the baseplate. In most cases, there isn't.

But we also have good drainage (a lot of gravel under the slab (I know because I was forced to dig up a power cable last year…. And the houses are on a slope, so the water drains off well. This reduces the risk of problems.

Sounds reasonable! Do you have any idea how common moisture problems in baseplates are in your area? I don’t know how representative an answer to that would be, but I’m trying to understand if this is an exaggerated issue that those who have been affected write about on internet forums or if it’s a common problem in real life. Both my parents and in-laws live in areas from the late 70s and they look completely puzzled when I ask, as if they’ve never even heard the word baseplate. So it seems like it’s not a common topic among neighbors. If people had been replacing baseplates left and right, it would probably be known.

 

[Satsuki]

Sounds reasonable! Do you have any idea how common moisture problems in sill plates are in your area? I don't know how representative an answer to that would be, but I'm trying to understand if this is an exaggerated problem that those who have been affected write about on internet forums or if it is a common problem in real life. Both my parents and in-laws live in areas from the late 70s and they look completely puzzled when I ask, as if they've never even heard the word 'syll' (sill). So I'm thinking it doesn't seem to be a common topic among neighbors. If people had been replacing sill plates left and right, word would have gotten around.

On our street with 12 houses, 2 have replaced sill plates, and we are one of them. In recent years, 5-6 houses have been sold in the area, and none of them have replaced sill plates, so I assume that during inspection, no increased moisture levels were detected or any odor noted. We replaced because one sill plate was a bit high (around 16%), likely due to plants against the house wall and an extension that kept the wall in the shade all day. Those who replaced them said that the sill plates on other sides were in very good condition.

My best advice regarding sill plates is to talk to a few neighbors - if there are problems (due to geology and building techniques), often several houses in these 70s subdivisions have similar issues. If the neighbors say most have replaced their sill plates, it's likely a problem in that particular area. If the neighbors look like living question marks, it's probably not an issue there...

And of course, sill plates do not stand in 100% moisture, that would be like them standing in water. If that's the case, then there are other, more urgent, problems, like a water leak/flood...

 

[kallekarwe]

On our street with 12 houses, 2 have replaced their beams, and we are one of them. In the last few years, 5-6 houses have been sold in the area and none have replaced their beams, so I assume that during inspection they did not measure increased moisture content or note any smell.
We replaced because one beam was a bit high (about 16%), likely due to plants against the house wall and an extension that caused the wall to be in shadow all day. Those who replaced told us that the beams on other sides were in very good condition.

My best tip regarding beams is to talk to some neighbors - if there is a problem (due to geology and building technology) often several houses in these 70s housing mats have similar problems. If the neighbors say most of them have replaced beams, it is likely a problem in that specific area. If the neighbors look like living question marks, it is probably not an issue there....

And of course, beams don't stand in 100% moisture, that would be like standing in water. If that is the case, you have other problems, more acute. Like a water leak/flood....

Thanks! Sounds reasonable all around.