Replaced some beams and will rebuild and insulate. There is about 40cm from the foundation to the underside of the beams, and there is sand on the foundation, which feels dry and nice. The previous construction consisted of a bottom liner made of planks, newspapers, and then sawdust. I will insulate with Ekovilla boards now, what should be used for the bottom liner? Replace the newspapers with paper? How do I best build without plastic?
There are special bottom boards that resemble masonite but are thicker. There is also borbehandlad plywood designed for this purpose. When it comes to the sealing between the bottom board and insulation, I think you should follow the manufacturer's (of ekovilla) instructions.
The newspapers were probably just to prevent the sawdust from falling through the board gaps.D D746 said:
Here's what I did in a similar situation: Removed the saw/cutter dust and newspaper pages (they were, by the way, from the war year 1915). Laid a subfloor of 10 mm construction plywood, and sealed along beams and board joints with exterior sealant.
Then laid Gullfiber.
I chose construction plywood because I have the impression that fiber boards, masonite, and similar materials tend to warp under the weight of the insulation if it's a bit humid, and that can create an annoying gap between the insulation and floorboards, which often leads to cold floors.
Start by digging a hole in the sand under the house; when you reach about 70-80 cm and it's still completely dry, then maybe.
But the torparegrund worked in the past precisely because there was no insulation in the floor, and they also had a warm chimney standing directly on the ground. This made the ground a few degrees warmer, so moisture in the ground couldn't condense under the house. Moisture passed up through the floor.
Today, ground moisture is prevented from rising using durable plastic, possibly with a layer of clean sand or isodränkross, and ventilation of the space.
But the torparegrund worked in the past precisely because there was no insulation in the floor, and they also had a warm chimney standing directly on the ground. This made the ground a few degrees warmer, so moisture in the ground couldn't condense under the house. Moisture passed up through the floor.
Today, ground moisture is prevented from rising using durable plastic, possibly with a layer of clean sand or isodränkross, and ventilation of the space.
What nonsense is that?L Leif i Skåne said:
30 - 40 cm is good enough, why would you need 80 cm down to dry soil?
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I meant to do a test on how far down it is "feels dry and nice"D D746 said:
If the ground is moist after a few dm down, then put plastic on the ground.
Have you tested for radon? Otherwise, it's now that the radon membrane should be put in place.
The house is from 1905. Sometime around 1945, they added sawdust to the beams, and in 1975, water was added to the house and the room. The beams I replaced were bad due to a floor drain that wasn't sealed properly; around it is fine despite the sawdust insulation from '45. Therefore, I thought of building in a similar way without plastic since it seems to work. But replace the sawdust with ekovilla, which should have the same properties. But can I replace the planks that were used as the sub-layer with k plywood? The paper is just to keep the sawdust in place, so can I skip it? Or does it have another function? According to ekovilla, you should have paper on the warm side of the insulation in the floor, but it feels unnecessary in this construction?
As Leif in Skåne mentioned, torpargrunder managed well in the past thanks to the chimney keeping it dry down there through continuous firing. If you are not also continuously firing - the conditions have already been disrupted - and the old solution may therefore be risky.
Yes, I understand that, but since 75, electricity has been used as the main heat source, and it is still in good condition. Except in the bathroom, the sawdust insulation and old floors will remain in the rest of the house. But what do you think about skipping the paper and using plywood instead of planks in the crawl space?L Lärospånet said:
L Lärospånet said:
If you want to drive really healthy and eco-friendly, I wouldn't use k-plyfa - or at least try to find the one with the least formaldehyde to avoid potential emissions. Regarding the cardboard - have you tried asking Ekovilla?
When we dug up the root cell and fixed a new floor in the cottage 30 years ago, we used some kind of oil-hardened plywood that was supposed to be for the subfloor, bought at a regular hardware store. This past summer, I needed to replace the kitchen floor, and we happened to step through the insulation and the subfloor. Everything underneath looked brand new, not even a cellar smell, it just had a dry scent of sand. And yes, we laid building plastic over the sand on the ground 30 years ago, I don't know if it has made any difference but it looked good anyway. Considering all the scare reports, sometimes it works out just fine actually. It's about 40-60 cm to the ground, and we have a few apertures in the retaining walls, that's it.D D746 said:
old thread I knowL Lärospånet said:
Do you have any advice regarding the radon membrane and the aspect that it is diffusion-tight? I am facing fixing a mullbänk, we likely cannot dig so deep and risk the foundation stones moving. (We are considering hasopor)Hi, I assume you're asking me: I don't think we have a problem with radon (due to the type of ground), and since I wrote this, I've concluded that we will not try to have a radon barrier (among other things because it is not a residential building). However, I am still interested in the challenge that a barrier presents in combination with older tried-and-tested solutions, as we are also facing the task of restoring an old parstuga. So, if any experienced person is willing to share experiences 🤓Oldboy said: