By the way, I saw that Casos boardfix only requires one kilo per m2, which results in a square meter price of 33kr. Completely OK.
K Kojfabriken said:
Interesting, you don't happen to know what it's called? I've been searching around, but without finding anything. Is it a kind of primer that allows the sheet adhesive to stick?nino said:
Hello again, I have pondered and done further research. I've also read a bit about Ardex 7+8/8+9. I might possibly go with that, but I have another solution in mind that I find interesting.
Above the battens and the plates, one might be able to screw in an oil-hardened board, 3 mm with plenty of small screws (through the plates and into the battens). This provides a firm base to screw glue the floor gypsum to.
To glue the double plasterboard, I will use Casco's board glue. (Casco boardfix). SEK 330 for 10 kg. Cheap (compared to Ardex) and made for the purpose
.
The alternative (in addition to Ardex 7+8 and S48) is to put in a layer of floor chipboard and a layer of floor gypsum, but it might have thermal inertia, requiring a higher temperature difference, which I want to minimize, as I have an air-to-water pump. It would also be higher, meaning I'd have to raise three door frames. (though I probably have to do that anyway)
alt. 1, Board (3mm) + gypsum (12.5) + gypsum (12.5) = U-value 8.6
alt. 2, Chipboard (22) + gypsum (12.5) = U-value 5.8
= Big difference in required temperature difference. To utilize the pump's full capacity (when it's cold outside) (6kw) (calculated assuming the entire house of 65 m2 would have the current setup), it requires alt. 1 11 degrees temp.diff. between the plates and the floor surface. Adding a random guess of 3 degrees more for losses between boards, hose, and plate, ceramic material, etc. (note: less important since it applies to both alternatives) yields a 14-degree temp difference. It would need to be up to 28 degrees on the surface, resulting in a water temperature of 42 degrees. All else being equal, with alternative 2 it would be 47 degrees in the hose, which is not a negligible difference when it's minus 15 outside.
Above the battens and the plates, one might be able to screw in an oil-hardened board, 3 mm with plenty of small screws (through the plates and into the battens). This provides a firm base to screw glue the floor gypsum to.
To glue the double plasterboard, I will use Casco's board glue. (Casco boardfix). SEK 330 for 10 kg. Cheap (compared to Ardex) and made for the purpose
.The alternative (in addition to Ardex 7+8 and S48) is to put in a layer of floor chipboard and a layer of floor gypsum, but it might have thermal inertia, requiring a higher temperature difference, which I want to minimize, as I have an air-to-water pump. It would also be higher, meaning I'd have to raise three door frames. (though I probably have to do that anyway)
alt. 1, Board (3mm) + gypsum (12.5) + gypsum (12.5) = U-value 8.6
alt. 2, Chipboard (22) + gypsum (12.5) = U-value 5.8
= Big difference in required temperature difference. To utilize the pump's full capacity (when it's cold outside) (6kw) (calculated assuming the entire house of 65 m2 would have the current setup), it requires alt. 1 11 degrees temp.diff. between the plates and the floor surface. Adding a random guess of 3 degrees more for losses between boards, hose, and plate, ceramic material, etc. (note: less important since it applies to both alternatives) yields a 14-degree temp difference. It would need to be up to 28 degrees on the surface, resulting in a water temperature of 42 degrees. All else being equal, with alternative 2 it would be 47 degrees in the hose, which is not a negligible difference when it's minus 15 outside.
I can announce that I have now bought building materials and started screwing on the following solution;
22mm chipboard, 28mm battens, 3mm hard board, Casco's glue, 12.5mm floor gypsum.
This way, I only have one layer of gypsum and a Masonite board (+glue) above the plates. I know double gypsum can be good, but I really want to minimize the heat differential and with this solution, I get a U-value of up to 14 (not including tiles, adhesive, and glue).
The idea is that the Masonite board is screwed into the battens along with the plates. I have bought a bunch of small wood screws, but I'm afraid the heads will press right through the Masonite, so I'm going to buy mounting screws with a large flat head instead.
If I had started from the beginning, I probably would have used self-leveling compound. You probably can't get a higher U-value, but now I already had plates that I bought last year and battens that I also already bought.
22mm chipboard, 28mm battens, 3mm hard board, Casco's glue, 12.5mm floor gypsum.
This way, I only have one layer of gypsum and a Masonite board (+glue) above the plates. I know double gypsum can be good, but I really want to minimize the heat differential and with this solution, I get a U-value of up to 14
(not including tiles, adhesive, and glue).The idea is that the Masonite board is screwed into the battens along with the plates. I have bought a bunch of small wood screws, but I'm afraid the heads will press right through the Masonite, so I'm going to buy mounting screws with a large flat head instead.
If I had started from the beginning, I probably would have used self-leveling compound. You probably can't get a higher U-value, but now I already had plates that I bought last year and battens that I also already bought.