I am planning a garage and considering casting a floor structure for the upper level. The span will be about 6.1m free-spanning and approximately 20cm thick. (this needs to be calculated by a structural engineer) As an alternative to Plannja's combideck, I am considering forming with polystyrene with cleats that are then cast in place.
The question then is how to handle the door that will be hung from the ceiling. Can you attach beams under the polystyrene with long screws that are then cast into the concrete to secure the door? This solution should work for spaced paneling which I then put plasterboard on. But the question is whether it will hold for the door?
It was a bit mixed up earlier, it should of course be about 30cm thick vault.
But after a bit more googling, I found something called "TW-vault," which I hadn't heard of before, but it seems promising. Has anyone heard of this? (it might go by a different commercial name.) http://biphome.spray.se/thomas.wellander/
It's really no stranger than that in my case one would shape with Styrofoam and recesses with C/C 60 cm for the beams. Something similar is done at the house over a small basement part but with four beams C/C about 2m and a thicker slab about 15cm. The advantage would be that the self-weight is kept down and the amount of concrete is significantly reduced, although more reinforcement and Styrofoam would be required.
I have discovered that Träullit or equivalent is quite convenient. The sheets can be laid out and then form the ceiling in the garage, add reinforcement and finally bring in a concrete truck to fill on top. As a bonus, it becomes soundproofing in the garage.
I checked a bit on the manufacturer's website and it certainly seems like a suitable solution, at least for the surface in the ceiling. But I don't think you can attach a door to it, so that part of the question remains.
Does anyone have experience with my suggestion to use long screws through foam/plasterboard and into the concrete vault?
Or anyone else for that matter who has opinions on the proposal. The idea is that the long screw is cast in place and then it should really hold well, right?
I made a quick sketch of the proposal for the floor slab with a frame around it. It might be a bit easier to understand what I mean.
Gray is the lightweight concrete wall with recesses for the edge beam of the intermediate floor slab.
Blue is the foam plastic (possibly wood wool underneath) which becomes the permanent formwork.
Green is the cast vault including "beams".
It would require rather long screws in that case, plus a long drill bit to make holes. I would probably aim to drill straight through, thread a rod with (possibly countersunk) nut on top.
If starting with a wooden wool ceiling, can you then hang the track for the sliding door without the door itself (for weight reasons) with a through bolt fastened to the rebar?
Alternative three: Make holes in the formwork and drop a few concrete studs down to the inner ceiling to bolt the door to. That is probably also the most future-proof if you want to switch to a door with a slightly different mounting dimension.
I'm looking into several options for the intermediate floor, including filigree, hollow core, lightweight clinker, etc.
The common factor for these is that a crane is needed to put them in place, plus it's a bit cramped to get onto the plot. For this reason, a permanent formwork would be easier to manage. (From that aspect, otherwise it becomes quite a bit more work.)
When it comes to screw length, it depends somewhat on how thick the lowest layer of foam insulation is if attaching to the beams. Using a threaded rod that you drop through the foam insulation is an idea that could work.
If you go with the foam form solution, you need some kind of "form" underneath that can be propped. This could consist of studs instead of sparse paneling, which then also becomes part of the permanent formwork and can serve another function when the casting is complete.
I know I might be off with this, but it's fun to explore some personal ideas for solutions! That's half the fun of building!
Can't you just make a regular arch and create a wooden mold that you demolish and then build the house with...that's what I did with my previous house and I had very little waste....
Can't you just make a regular arch and create a wooden mold that you demolish and then build the house with...that's what I did with my previous house and ended up with very little waste....
Yes, the idea is to reduce waste in order to keep the overall cost down. Since I will be doing most of the work myself (and apparently, according to my wife, my hourly rate is low... ), it doesn't matter as much if it results in a little extra work.
How did you make the mold? Rough lumber that was later used for the roof? Did you have plastic in between, or how did you handle the contact surface with the concrete?
If my proposal turns out to be viable, it reduces the concrete amount from 16.5m3 to 9.6m3, which saves about 10k SEK. Then, of course, reinforcement is needed in both cases (although the amount and type will differ) as well as foam/mold. So it's not certain which will be cheaper.
For now, I am in the planning phase of the garage construction, see http://www.byggahus.se/forum/smahus...231268-garage-i-sluttning-med-ovanvaning.html. So far, I have only gotten a price for lightweight concrete arches, and it came in at over 50k SEK, including transport and assembly. My hope is to get below this, preferably down to 30-35k SEK.
I used OSB that I coated with plastic and reused...45x95 or 45x120 as studs and stamps...
Polystyrene with 30cm spacing that was reinforced with 12mm iron I believe...the slab ended up being 8-9 cm plus the thickness of the polystyrene...check with a designer regarding the measurements....
