Sorry for tricking you into reading this again. :-[ 
:-* But doesn't anyone have any thoughts on this material?! MTE MassivTräelement from www.ekologibyggarna.se. I would be very grateful for some input! ;D
We are still so interested in the material that this weekend we will be going to Borås and Vadstena to look at some houses built with this.
The "building slab" is made of several layers of cross-glued wooden boards, up to a thickness of 272mm. It can be used as walls, floors, and roofs. The exterior and interior can be larch, spruce, or pine.
If you choose a 25cm thick "slab" for the exterior wall, they claim no insulation is needed. The heating requirement is, according to them, less than 90kwh per sqm per year. A "normal house" consumes significantly more than 100 kwh.
I think the idea seems appealing, and it would be great to have walls that you can thump your fist on without them swaying or rattling....
:-* But doesn't anyone have any thoughts on this material?! MTE MassivTräelement from www.ekologibyggarna.se. I would be very grateful for some input! ;DWe are still so interested in the material that this weekend we will be going to Borås and Vadstena to look at some houses built with this.
The "building slab" is made of several layers of cross-glued wooden boards, up to a thickness of 272mm. It can be used as walls, floors, and roofs. The exterior and interior can be larch, spruce, or pine.
If you choose a 25cm thick "slab" for the exterior wall, they claim no insulation is needed. The heating requirement is, according to them, less than 90kwh per sqm per year. A "normal house" consumes significantly more than 100 kwh.
I think the idea seems appealing, and it would be great to have walls that you can thump your fist on without them swaying or rattling....
Well, that might be something. If you're looking for real wood, you can also check out the following link:
http://www.byggledarna.se/baltiskavillor.htm
House frames in glued laminated timber, it's possible to build fairly massive houses with it as well, and the price isn't too steep either.
http://www.byggledarna.se/baltiskavillor.htm
House frames in glued laminated timber, it's possible to build fairly massive houses with it as well, and the price isn't too steep either.
Sure, but in our "self-build," I probably benefit most from making a good procurement rather than building myself.MathiasS said:
Nice to get some input. Will of course post my comments after the weekend's impressions. According to (as yet unconfirmed) information, this material would mean building costs lower than average.
Sense and balance!
Solid wood does not insulate particularly well.
It insulates maybe about ten times worse than mineral wool.
To me, that sounds like "sales talk."
What is all the wood good for? It is not needed for structural reasons
to support the house.
It insulates poorly against heat loss.
What are really the advantages of solid wood?
KoW
Solid wood does not insulate particularly well.
It insulates maybe about ten times worse than mineral wool.
To me, that sounds like "sales talk."
What is all the wood good for? It is not needed for structural reasons
to support the house.
It insulates poorly against heat loss.
What are really the advantages of solid wood?
KoW
Well, it's precisely because we're a bit uncertain that we want some comments. I realize that a conventional log house, say with 15 cm thick logs, requires insulation. The point with this material is that you can avoid insulation and interior walls in that case. The argument from the sellers is that since the walls are made of cross-laminated timber boards, the walls have better insulation properties. We're unsure if this is true...
Do you know where one can read about wood's insulation capacity? I haven't found anything really informative.
In any case, on Saturday we will see the house that has 272mm thick walls (and no insulation) and talk to the owners. We will also meet Ecologibyggarna and ask them to provide evidence that this works. We are eager to build a house with as sustainable an ecological future perspective as possible, without PVC plastics, mineral wool, and self-leveling compound. Don't think that we're total back-to-the-land people! On the contrary, we are economically minded and scientifically oriented, flummery is not for us.
Do you know where one can read about wood's insulation capacity? I haven't found anything really informative.
In any case, on Saturday we will see the house that has 272mm thick walls (and no insulation) and talk to the owners. We will also meet Ecologibyggarna and ask them to provide evidence that this works. We are eager to build a house with as sustainable an ecological future perspective as possible, without PVC plastics, mineral wool, and self-leveling compound. Don't think that we're total back-to-the-land people! On the contrary, we are economically minded and scientifically oriented, flummery is not for us.
The Home Cat
I had an excellent booklet, bought at the building center,
called Träfasader. It contained EVERYTHING, including heat transfer coefficients (is that what it's called?) for different materials.
Studied it diligently when I renovated our previous
1810s house.
Can't find it now after the move, but I will look for it over the weekend.
KoW
I had an excellent booklet, bought at the building center,
called Träfasader. It contained EVERYTHING, including heat transfer coefficients (is that what it's called?) for different materials.
Studied it diligently when I renovated our previous
1810s house.
Can't find it now after the move, but I will look for it over the weekend.
KoW
some numbers
Thermal conductivity (lambda)
wood with density 0.4-0.7kg/dcm3 and 10-15% moisture = 0.13
glass wool mat (density 0.10kg/dcm3) = 0.031
stone wool mat (density 0.11-0.16kg/dcm3) = 0.032
wood fiber boards: semi-hard = 0.07, hard = 0.12
sawdust = 0.09
wood shavings loosely packed = 0.06
figures come from an engineering book from 1940 but they don't change over time. What changes over time is just the names of different materials
Wood is about 4 times worse than mineral wool, right? :-/
It's the still dry air that insulates!
gaia
Thermal conductivity (lambda)
wood with density 0.4-0.7kg/dcm3 and 10-15% moisture = 0.13
glass wool mat (density 0.10kg/dcm3) = 0.031
stone wool mat (density 0.11-0.16kg/dcm3) = 0.032
wood fiber boards: semi-hard = 0.07, hard = 0.12
sawdust = 0.09
wood shavings loosely packed = 0.06
figures come from an engineering book from 1940 but they don't change over time. What changes over time is just the names of different materials
Wood is about 4 times worse than mineral wool, right? :-/
It's the still dry air that insulates!
gaia
Hello,
I have looked at their website and done some calculations.
It is true that the wall will be sturdy and withstand a storm, but it must be an expensive wall?
They mention nothing about the wall's insulation capability, and it's obvious why.
Massive wood does not insulate particularly well. A wall with 272 mm of massive wood gets a U-value of 0.473 which should be compared with a wall with 95 mm of mineral wool that has about 0.431, and no one builds such outer walls today.
The question is whether it is approved to build with this type of outer walls considering the poor insulation value.
Best regards,
Johan
I have looked at their website and done some calculations.
It is true that the wall will be sturdy and withstand a storm, but it must be an expensive wall?
They mention nothing about the wall's insulation capability, and it's obvious why.
Massive wood does not insulate particularly well. A wall with 272 mm of massive wood gets a U-value of 0.473 which should be compared with a wall with 95 mm of mineral wool that has about 0.431, and no one builds such outer walls today.
The question is whether it is approved to build with this type of outer walls considering the poor insulation value.
Best regards,
Johan
Hi, it sounds a bit interesting with a solid wall element. What I can imagine is that it avoids the problem of deep cracks that a wooden log always has, thus achieving a significantly better lambda value than a normal log wall. Furthermore, such a house should have a more consistent living climate throughout the year, absorbing moisture during the wet summer/autumn period and releasing it during the dry winter period, thereby providing a more stable indoor climate.
Well, unless you have a vapor barrier on the wall. If you don't, you have to be careful with too much insulation so that the dew point doesn't end up inside the wall, because then it will rot pretty quickly.
Without cracks, the lambda value will probably be higher = poorer insulation ability, somewhat depending on how they are oriented.
Without cracks, the lambda value will probably be higher = poorer insulation ability, somewhat depending on how they are oriented.
Read your comments with interest. With the lambda value, it was necessary to have a corrected one to obtain a fair value (according to Chalmers, builders, and engineers). I'll get back in a day or so (when I understand it myself so that I can explain) and will hopefully have sorted out the images by then as well.
With the lambda value, it was necessary to have a corrected one to obtain a fair value (according to Chalmers, builders, and engineers). I'll get back in a day or so (when I understand it myself so that I can explain) and will hopefully have sorted out the images by then as well.