written by Rene K. Mueller, Creative Commons CC BY NC 2014, last updated Sun, January 18, 2015
Here a reverse chronological diary (newest entry first) experimenting, building and living in LC Domes:
Yesterday it snowed a bit, and I watched the snow falling on the dome carefully and once pushed so the snow slid down.
The LC Dome is not suitable for winter time with snowfall, and if you decide to still use it with snow, constant supervision is a must.
4m 3:3:2 LC Dome pitched again
The ground is again frozen, so some of the wooden anchors I couldn't ram further into the ground and still not fully stable, but I replaced the broken PVC pipes, and pulled the PE cover over the skeleton.
Some rain and perhaps snow falls is expected later this week, and I will take care it won't collapse again.
For sake of reference, I used PE before for Yurt setup successfully, where the heavy and humid snow slid down by itself, with this dome setup there is risk of snow remaining on the construction.
Pitching partial skeleton again
Apprx. 7x 2m x 25mm PVC conduits broken
After a warm and rainy night, most of the snow is gone so I was able to sort out the PVC bows.
Apprx. 7x 2m x 25mm PVC conduits got overbent and mostly broke as well, which is more than I expected.
I do have spare PVC conduits and will replace those and hope should new snow arrive I will be around to prevent a collapse again.
Needless to say, this shows the limits of the "Low Cost PVC Dome", and also the reason I document it: it has its limits, and one has to be aware of it.
Collapsed due heavy snow
I was away a few days, and came back just after it began to snow for 9 hours, heavy humid snow, apprx. 10-15cm thick, with a bit wind.
Usually with PE snow slides away, but with a dome there are some area which is rather flat, on the top, so that's the result of unattended temporary buildings like with LC 3:3:2 4m with 25mm diameter PVC.
As soon the snow and ice is decreased, I gonna re-pitch the dome again as it's a shelter for some material storage.
I took one LC 3:x:2 4m dome down, and use the parts for a geodesic dome, yes cutting it, but I need straight pipes and I came up with this procedure:
Btw, I keep one LC 3:3:2 4m dome with shelter some material, as it saw it's slightly more stable than the 3:x:2, in particular when the rain cover is thrown over the skeleton and now hang inside.
Last a thunderstorm with brief but strong winds approached my site, heavy rain for a few minutes: both LC domes remained stable.
Since I didn't attach the full rain cover on the 3:x:2 4m LC dome that cover moved a bit, and so I attached it more firmely.
Currently 2x LC domes stand, 3:x:2 and 3:3:2 each using 32x 2m x 25mm PVC tubes, total 64x 2m x 25mm PVC tubes, whereas 4x 2m were cut to 1.73m to fit the 'x' in 3:x:2.
I will keep one LC dome for storage, but make an 2v icosahedron geodesic dome, as described in Geodesic Dome Diary.
I haven't come up with a decent solution for the door for the LC Dome, here an improved door: I used two 2m x 16mm PVC tubes to form 3/4 ring, and wrapped the PE rain cover around:
It would permit a simple hanging piece of PE to be the actual door - have to think about the actual wrapping and attachment of the door bow.
As you can see the PE rain cover isn't yet cut, will do as next and attach the PE rain cover at the bottom ring solely.
Two LC Domes are pitched currently today and perhaps for the next few days:
- front: 3:3:2 4m diameter with a partial blue cover, and
- back: 3:x:2 4m diameter with white PE rain cover meant for a 5m dome (excessive material on the base).
A 4m diameter dome is sufficient for a single person given the cover lays over the skeleton, but for a whole year usage with additional insulation for the winter time, an offset inside of at least 10cm is required, making it 3.80m or even less which makes already a big difference - too small for my use case.
I also was exploring the possibility to connect two LC domes with a gateway or so.
3:3:2 LC Dome (4m diameter)
Today I pitched another LC Dome, after I did the base ring and main 3x 2m bows, and the smaller 2x 2m bows and as next was about to cut some tubes/pipes for the x in 3:x:2, actually cutting 2m to 1.75m - but since I consider another dome to put up I hesitated to cut and thought of a way to finish the dome without cutting any tubes/pipes.
The result was the 3:3:2 LC Dome, the other 3x 2m bows attached at the same points at the base, yet, tilted to cross over at the top on the side.
What was more challenging was the fact so many bows with the same length crossed each other - and more sophisticated procedure to wave to compensate the distance introduced with the "OBO quick" clips I used to fixate the crossings.
I gonna document the details of the 3:3:2 LC Dome within the next days on the first page.
Tent in a Tent (3:x:2 4m LC dome)
Straighten tubes again
The last days it rained a lot, and I moved my camping tent inside the 3:x:2 4m dome, covered by the larger rain cover which was meant for the 5m dome.
Some of the spare tubes I placed on the ground to straighten again for future use.
Combining 3 tubes together
I also thought of combining 3x tubes together, to make them stronger, but the overhead wasn't worth the small benefits - the 25mm diameter 2m PVC tubes aren't doing well used as 4x => 8m bow, but with 3x => 6m bow they are sufficiently stiff to make a LC dome.
Since the 4m dome is too small for my use case, I am pondering on a 2nd 4m LC dome, or a 5m geodesic dome, either
- 5.0m 2v icosahedron with 85 PVC tubes (30xA=1.40m, 35xB=1.58m), or
- 4.7m 3v 5/9 icosahedron with 165 PVC tubes (30xA=0.83m, 55xB=0.96, 80xC=0.98)
reusing the 2m tubes.
Storm bent 5.1m 4:x:3 LC Dome using 25mm tubes/pipes
Heavy rain and strong winds approached my site, I was away, and pushed the dome down despite my efforts to tie the dome, but when you look how it bent, it becomes clear what the problem is:
The bows are too weak, or too wobbly - even fixating some of the junctions doesn't prevent the dome to bend. I also didn't had a proper door as I noticed the wind found its way into the dome.
Important Conclusion: 4x 2m bows with 25mm diameter (4:x:3 5.1m LC Dome) is too weak to do, even when a rain cover adds integrity, but the weakness of the bows remains.
As I wrote before, but repeat here: the best would to use 32+mm diameter PVC 2m tubes for > 6m long bows, but the fitting of those electrical PVC conduits is only 30mm long, too short to reliably connect 32+mm diameter 2m or 3m long tubes - this is why I tried this with 25mm diameter only tubes until now.
Also, no part got broken, where too much force was applied the tube connectors let go the tube (e.g. at the base) - it is one of my other objectives with LC dome to keep it modular, simple to assemble, and disassemble in case of strorm in a way so no parts are broken.
Since the entire LC Dome approach is rather modular, I disassembled the 4:x:3 dome and made a 3:x:2 4m dome instead (no photos).
Storm bent 5.1m 4:x:3 LC dome, with 2m x 25mm tubes:
Storm bent LC dome
Horizontal ring opened
Laying aside after storm
After the few days drying the inside, I close the dome and anchor the dome finally - but before I did this, I digged an additional 2nd small drainage just where the rain cover will reside at the top of the slope:
I deliberately made two drainages, one for the water coming from the hill, and the other from the water from the rain cover - and since I'm positioned on the slope the drainage is only on the "back" side facing the hill slope.
The next days a significant drop of temperature with heavy rain and thunderstorms are expected - a test for my overall setup. If it succeeds, I gonna start to move actual living equipment inside the room and also attach the interior canvas.
While using a electric fence band, found on-site, to fixate the dome *), I realized some of the captures where not fully enclosing the bottle caps I used as "captures" to attach the PE rain cover, so I corrected those.
The wire hooks really turned out well, I was able to detach the rain cover quickly and work myself to the last top 5 hooks I left, and put the fixation band over it - in a way so with the pull the connection are strengthened; although this runs against the concept a bit to let the dome fall apart without breaking any parts in case of heavy winds or storms - but the last thunderstorm kind made me more conscious of the weakness of the "Low Cost Dome (PVC)", the entire dome is or was still too wobbly and bent in when wind pushed from one side.
So, it's more stable now, but also introducing possibilities where parts may break when pushing the dome forcefully.
Band fixating top junction (over, below-other-side, over, below-other-side, over)
More details on the band fixing the bow junctions
Dedicated peg to fix the fixation band
*) Many of the details were resolved with material I found on-site, e.g. the heavy use of various wires.
Performed tasks today:
- wooden pegs to anchor the base ring (apprx. 30-40cm or 1 feet or arm length)
- wood chips to prepare path to entry
- wooden peg detail: hook hangs on the base ring, tied with wire to the wooden peg; the cover will connect to the base ring at the same position, this allows to detach the cover without detaching from the wooden peg; I used wire because I still have some left over, I could have used a cord as well
- cutting the door
- digging some more drainage around the place; you see the outer drainage, an additional I will dig where the rain cover reaches the ground
- opening the cover to dry the ground (it rained on it before I put up the cover)
Wooden pegs to tie the ground ring
More wooden chips to prepare path to entry
Detail: wooden peg with wire to hook on base ring (not directly connect other hook)
Cutting the door
Extending the drainage
Opening the dome, wrapping up the rain cover to let the inside dry
After a week pause I continue with the dome, putting up the cover again - the positions to the bows junctions to the cover connectors have changed slightly.
The problem is that the entire ground has a slope which causes the entire dome lean forward toward the position the photos were taken (south).
I only adjusted one connector, all others I left as they were. As next I ram some small wodden pegs into the ground to anchor the dome properly.
About the door I haven't decided yet, whether an framed door, flap like door, or round door with a flap like with a tipi - I also consider to make two doors to create some draft during the summer.
Other things I have pondered on:
- air openings / ventilation outlets so the humidity can leave the dome, but no rain can enter
- a flexible window to let (sun)light in and see outside.
The day before yesterday I realized it would be nice to add an additional line of connectors in the vertical, where the open 7a ring resides to fasten the rain cover - which means more Wire Captures
Also got more bottle caps, and made about 30+ Ghostly Connectors
, sufficient to attach then the rain cover at the planned points.
Unanchored dome flew away during thunderstorm (no actual parts broken though)
Skeleton pitched again
A thunderstorm approached my location with 100km/h+ winds, and within 10 minutes misplaced 2/3 fastened rain cover and unachnored (bad mistake) dome about 5m - so far no parts are broken, one pipe was overbent and replaced, no cover torn - the mix of wire-based connectors and hooks worked so far.
The plan was to keep the site dry, so I had it covered at rain the last days, and uncovered at sunlight, but last night it rained a few hours - which means, I have to redry the wood chops covered place again during the next week, or choose another covering (sand, gravel or alike).
The next days it will be rainy, so not much work can be done at the site - I need 1-2 days dry so be able to finish the setup and anchor the dome properly, perhaps get the interior cover as well to add more weight of the overall setup.
Later the week I'm away for a few days, so likely next weekend continue with the dome setup.
Next Page >>
- Page 1: Notions, Reflection, PVC Conduits, 2m PVC Tube, 3m PVC Tube, Considering Fitting, Temperature Range ...
- Page 2: Diary, 2015/01/18: A Bit Snow Again, 2015/01/06: Pitched Again, 2015/01/03: Snow Gone, 2014/12/29: Collapsed Due Snow ...
- Page 3: 2014/07/04: Rain Cover & Storm, 2014/07/03: Preparing Rain Cover, 2014/07/02: Cover Setup ...