I have cast with leca balls and it turns out great... must try Styrofoam balls...
If you cast smaller areas, it's probably too expensive to order pre-mixed...
So if you can do it yourself, that's great. It might get a bit tricky if you want to sand the surface...
so then you'll probably have to pour another layer on top... This has to be tried...
If you cast smaller areas, it's probably too expensive to order pre-mixed...
So if you can do it yourself, that's great. It might get a bit tricky if you want to sand the surface...
so then you'll probably have to pour another layer on top... This has to be tried...
I was thinking about this:
It's possible they also have some additive. The art, of course, is to not have too fluid a paste.
Regarding the longer drying time that someone mentioned earlier in the thread - I don't know if it refers to the drying or the strength development. Many mix this up when it comes to concrete. Cement is, as you know, a hydraulic binder - meaning it reacts with water to create an end product that is not water-soluble. Concrete should thus not dry before sufficient strength has been achieved. If the concrete dries too early, there isn't enough water for the cement reactions, and in the worst cases, drying cracks can occur due to volume reduction.
As for the curing time, this should remain unchanged (at least not longer) - the EPS beads do not affect the cement reactions and hence do not affect the hydration time either. One could even speculate that it might be faster thanks to EPS's insulating properties. The hydration heat could be retained better in the construction, and since strength development is directly dependent on temperature, it might have a positive impact compared to normal concrete under certain conditions.
Regarding the drying (after the initial stiffening and early curing), it could also proceed faster. I assume EPS is more diffusion-open than concrete is - given the same water-cement ratio.
Cement has a density of 3.1 t/m3. If it is 16.5 kg of cement per bag, that corresponds to about 5.3 liters. (5.3 x 3.1 = 16.43 kg)jeppeknaster said:
It's possible they also have some additive. The art, of course, is to not have too fluid a paste.
Regarding the longer drying time that someone mentioned earlier in the thread - I don't know if it refers to the drying or the strength development. Many mix this up when it comes to concrete. Cement is, as you know, a hydraulic binder - meaning it reacts with water to create an end product that is not water-soluble. Concrete should thus not dry before sufficient strength has been achieved. If the concrete dries too early, there isn't enough water for the cement reactions, and in the worst cases, drying cracks can occur due to volume reduction.
As for the curing time, this should remain unchanged (at least not longer) - the EPS beads do not affect the cement reactions and hence do not affect the hydration time either. One could even speculate that it might be faster thanks to EPS's insulating properties. The hydration heat could be retained better in the construction, and since strength development is directly dependent on temperature, it might have a positive impact compared to normal concrete under certain conditions.
Regarding the drying (after the initial stiffening and early curing), it could also proceed faster. I assume EPS is more diffusion-open than concrete is - given the same water-cement ratio.
I did this exercise during the fall (i.e., made and used self-mixed EPS concrete).
Since I only needed to use the concrete as a rigid insulation between a newly built aerated concrete wall and an old brick wall, my load-bearing requirements were low.
I ordered EPS beads via a distributor to Cellplast Direkt for about 200 SEK/300l. This, plus the cement I needed, brought me to one-third of the cost of what I would have paid for pre-mixed EPS concrete in bags. (For me, pre-mixed EPS concrete from a central location was not an option because the concrete needed to be scooped/bucketed on-site. There was no distributor of dry mortar in bulk.)
The work process I finally thought was best was:
1: pour in an appropriate amount (50 l) of EPS beads
2: pour in a few liters of water and mix so that all beads become wet
3: add cement – mix horizontally so that the cement doesn't settle to the bottom immediately
4: add more water and mix until the right consistency is reached (preferably mix for a long time)
The outcome was decent, I think – I used a mixer (even though the instructions for EPS concrete state that you should use a hand mixer).
I would say that the amount of water was the hardest to get right, but you get a decent feel for it after a few tries.
I tried adding dish soap as it was suggested that breaking the water's surface tension was important – but I didn't feel it made a significant difference.
I also bought a couple of bags of ready-mixed polystyrene concrete from Finja for comparison. The size of the beads in these bags is certainly smaller than those I got from Cellplast Direkt. I think, however, that I managed to achieve a similar consistency with the self-mixed as with the pre-mixed, but it's quite possible (probable) that the strength is better in the pre-mixed.
I would probably do the same exercise again – but one should certainly ask whether it's worth the effort and consider that the load-bearing capacity is likely worse than ready-made bags.
Since I only needed to use the concrete as a rigid insulation between a newly built aerated concrete wall and an old brick wall, my load-bearing requirements were low.
I ordered EPS beads via a distributor to Cellplast Direkt for about 200 SEK/300l. This, plus the cement I needed, brought me to one-third of the cost of what I would have paid for pre-mixed EPS concrete in bags. (For me, pre-mixed EPS concrete from a central location was not an option because the concrete needed to be scooped/bucketed on-site. There was no distributor of dry mortar in bulk.)
The work process I finally thought was best was:
1: pour in an appropriate amount (50 l) of EPS beads
2: pour in a few liters of water and mix so that all beads become wet
3: add cement – mix horizontally so that the cement doesn't settle to the bottom immediately
4: add more water and mix until the right consistency is reached (preferably mix for a long time)
The outcome was decent, I think – I used a mixer (even though the instructions for EPS concrete state that you should use a hand mixer).
I would say that the amount of water was the hardest to get right, but you get a decent feel for it after a few tries.
I tried adding dish soap as it was suggested that breaking the water's surface tension was important – but I didn't feel it made a significant difference.
I also bought a couple of bags of ready-mixed polystyrene concrete from Finja for comparison. The size of the beads in these bags is certainly smaller than those I got from Cellplast Direkt. I think, however, that I managed to achieve a similar consistency with the self-mixed as with the pre-mixed, but it's quite possible (probable) that the strength is better in the pre-mixed.
I would probably do the same exercise again – but one should certainly ask whether it's worth the effort and consider that the load-bearing capacity is likely worse than ready-made bags.
Very interesting osfo. I noticed that Thermisol has a variant with slightly larger beads than EPS cement. 70-liter bags and twice as much water should be used.
http://www.thermisol.se/applikationer-losningar/isolering/thermisol-ready-mix
http://www.thermisol.se/applikationer-losningar/isolering/thermisol-ready-mix
http://www.thermisol.se/applikationer-losningar/isolering/thermisol-ready-mix
http://www.thermisol.se/applikationer-losningar/isolering/thermisol-ready-mix
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That people make their own beer, wine, and spirits I understand, but homemade EPS concrete is incomprehensible to me.:O
It's no wonder there are so many failed construction projects that never get completed.
Regards, Stickan
It's no wonder there are so many failed construction projects that never get completed.
Regards, Stickan
Considering that they seem to have increased the price of EPS Cement by over 50% since the summer, it seems more reasonable to make it yourself if you can manage it. Paid 160 kr in the summer and now they want between 230-290 kr/bag....
A few years ago, I mixed my own eps using sacco bags and cement. I used the mixture to roughly level a concrete vault about 100-150 mm before self-leveling compound and tiles. It worked well and hasn't sunk or caused any cracks. However, I did notice that the surface durability of my mixture was a bit lower than the "real" one, i.e., surface beads came off a bit easily, but that didn't bother me after the self-leveling compound.
On the contrary, I think. The EPS-cement doesn't even need to taste good.Stickan56 said:That people make their own beer, wine, and spirits I understand, but their own EPS-cement is incomprehensible to me.:O
It's no wonder there are so many failed construction projects that never get finished.
Best regards, Stickan
1: it depends on how you want to mess with the mixer later...Orix said:
2. got it refunded from a furniture dealer, so there was no fight..
1 cubic meter cost 1500:- at beanbag, it should be enough for about 20 bags (1000/50) and then about 330 kg of standard cement is needed, which costs 42:- per 25 kg bag. 14 bags * 42:- = 588:- so about 2100 + shipping will be around 100-120:- per bag including VAT. You save about 1000:- on 20 bags / 1 cubic meter compared to the bag price (which can be negotiated down when buying a pallet).
If you read above, Osfo got 300 liters of balls for 200 SEK, which gives a m3 price of just over 700 SEK. This can probably be reduced to 500 SEK if you want a whole cubic meter. Then suddenly it becomes half the price.
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Oh, I missed that...
That makes it even better
I have about 50-60 sqm that needs to be filled with about 6-7 cm, or maybe more
I have a very uneven floor that needs to be fixed, it will be the floor in the apartment
I was planning to fill with cement-bound leca to a fairly level height, apply self-leveling compound to make it even, lay 50 mm polystyrene and on top of that 22 mm chipboard
Considering making my own EPS now (I have the resources to buy ready-made EPS at net cost, but it's too expensive)
The question is whether to go ahead and apply about 10-13 cm with EPS, mill down waterborne heating, and then pour self-leveling compound and lay tiles instead...
That makes it even better
I have about 50-60 sqm that needs to be filled with about 6-7 cm, or maybe more
I have a very uneven floor that needs to be fixed, it will be the floor in the apartment
I was planning to fill with cement-bound leca to a fairly level height, apply self-leveling compound to make it even, lay 50 mm polystyrene and on top of that 22 mm chipboard
Considering making my own EPS now (I have the resources to buy ready-made EPS at net cost, but it's too expensive)
The question is whether to go ahead and apply about 10-13 cm with EPS, mill down waterborne heating, and then pour self-leveling compound and lay tiles instead...