Hi kids! This is Ollie the Octopus again, guest posting for Polar Bear PC. Today’s post is about how I built an igloo!
An igloo is a type of shelter made from snow. It was originally built by the Inuit people in Canada and Greenland, but since there’s also snow in Antarctica, I thought, “Why not?”
If you have been living in the tropics all your life and have no idea what an igloo looks like, then here is a link to some pictures.
Now, here is a picture of my (partially-completed) igloo:
First, notice that there is a second partially-completed igloo in the background. This is because it took multiple tries to make a good igloo. I was ready to give up, but then I remember reading in the November 3 posting where Eric said they had to “fail their way to success.” So I kept at it and eventually got it!
Second, notice the tents in the background. How does an igloo compare with a tent? Are there any advantages or disadvantages? Here are a few that I was able to come up with:
1. Both the igloo and the tent can get quite warm! The tent traps a lot of the heat from the sun, while the igloo tends to trap body heat from the occupants inside. Believe it or a not, a snow wall does not let a lot of heat pass through it. We can say that snow is a good insulator of heat.
2. The igloo is much quieter. Inside the tent, you can hear everything going around outside (such as polar bears talking, snowmobiles zooming about, and the tent itself flapping in the wind), but a snow wall does not let much sound pass inside or out. In fact, I could probably play a ukulele inside the igloo and someone outside couldn’t hear! We can say that snow is a great insulator of sound.
3. In my opinion, a tent is easier to set up. A few weeks ago I set up a tent in about an hour, but the igloo took me a whole day to build. On the other hand, the igloo will be easier to take down. I can just let it melt away when the sea ice breaks up.
4. An igloo is less expensive, but a tent is more colorful.
What else did you come up with?
Now, there are many ways to build an igloo. Today, I will show you one method that worked for me. Are you ready for a ton of fun (and work)? Let’s start by getting out tools!
The first goal is to cut blocks to build the igloo. In the photo, there is a block on the right that is ready to be used for construction. The tool directly to my right in the picture is called a snow saw. It’s basically a big saw that’s kind of like a bread knife that’s really good at cutting snow. The tool below and to the left of me is a shovel. It’s handy to use for popping the blocks out after cutting them with the snow saw. Behind me is a strap that I laid on the snow to help me cut straighter lines.
Polar Bear MH calls the snow in this location “styrofoam snow” because it pops out like big blocks of styrofoam — that’s super handy for building igloos!
So we have blocks. But one problem with stacking blocks into a dome is that eventually they will want to fall down, and so you’ll end up with a big pile of blocks again. How do we prevent this? Can you think of a few possibilities?
When I encountered this problem, I began cutting my blocks in trapezoidal shapes like this:
Can you see why? One way that I can explain it is, when something (such as gravity) tries to pull the block down, it wedges and gets stuck instead. At this point, the piece is sitting in compression (being squeezed) and the structure is quite strong.
(By the way, this is the idea that lets people (such as the Romans) build beautiful stone buildings with lots of arches. The blocks in an arch are sitting in compression. Don’t worry if it’s confusing; you’ll learn more about it in high school physics class!)
Now that we have the right idea, things are still, unfortunately, a little easier said than done. You see, in the graphic above, the trapezoid has a buddy to both its left and right to help hold it up. What do you do when you place the first block in a new layer? It will have no friend to its left or right and it will just fall down!
I think that the best way would be to find a couple of friends to help hold blocks in place until you finish a complete layer. At that point, the blocks will wedge into themselves in compression and that layer will be strong and complete. Unfortunately, I was building at a time when all my polar bear friends were asleep! (Well, Polar Bear PC was around, but he was mostly taking pictures.)
Here was my solution for solo work. I call it the Pizza Push In Method(tm).
In Step 1, we make some trapezoidal blocks, then balance them one at a time on the edge (not on the sloped part where they will fall in).
In Step 2, we go around shaving down the trapezoids a little at a time, smaller and smaller. Each time we shave a block, it will fall down a little more before wedging itself in place again. After all the blocks have fallen into the right location, pack some snow all around to finish up that layer!
Here is a picture of my completed igloo.
I cut and placed the top piece on top, then cut it into the right shape. For the door, I dug underneath, then threw uppercuts until I busted through the floor (it was pretty fast since I have eight arms).
And that was how I built an igloo! Happy New Year’s Eve!