How to build a rainbow igloo

I’ve always wanted to turn our front yard into a public space of some sort. One winter we created snow couches for people to hang out on. Annually, we chalk the brick at the front our our home rainbow. This Christmas took on our biggest project and built a rainbow igloo.

Full credit for inspiration goes to Daniel Gray. The moment I saw his original igloo three years ago I knew I had to do it. Kudos to Daniel for giving me a few tips when I reached out to him on Reddit as well.

Our family had some unforgettable moments building the igloo, reading and drinking hot chocolate in it, and causing a scene. People pulled over for pictures and I’d come home to random kids playing in it.

So how exactly do you build an igloo like this?

Lots of folks have been asking, so here’s some detailed instructions should you want to re-create something similar.

Collect 2L cartons. Lots of them. At least 400 if you can. You could potentially reuse some of the cartons,x but it depends on the way they freeze. I found only about 10% of them re-usable. I had friends change purchasing behaviours to help collect more milk and juice cartons. You could possibly get a local business to pass you used cartons in bulk. Rinse them out, dry them, and store them away for the big day.

Wait for ideal conditions. You’ll need at least a few inches of snow available and a string of deep cold days. Monitor the forecasts. 3–4 days to freeze your ice cubes, 2–5 days to build your igloo, and then time to enjoy it.

Make your coloured bricks.

1. Open the carton tops. Pulling diagonal corners is quickest.
2. Fill with water to the top fold of the carton.
3. Add 6–10 drops of food colouring. (You’ll need 6–8 28mL bottles of colour)
4. Set outside in below zero temperature for 3–4 days. You want to ensure that it’s frozen all the way to the core.
5. The easiest way to unbox the ice blocks is to bring them inside at room temperature for 90 minutes first.

Build your igloo

1. Start with a ring of blocks. Space them about an inch apart. You can do some math on the diameter/circumference you’re aiming for — the size of the foundation will drastically impact the number of blocks needed. I had a base ring 32 blocks and an opening 5 blocks wide.
2. Make snowcrete. This is the mortar that binds the blocks. Mix snow and warm water in a large container (pail or wheelbarrow). You’re aiming for a soft but not watery mixture that will stick to the blocks.
3. Stagger the blocks, vary the colours, and tilt as desired. I’m guessing a 3–5 degree tilt should be sufficient, and we didn’t start tilting till a third of the way up.
4. Build the opening arch and begin spiraling the blocks. Now that there’s a complete circle layer the rings of blocks in a single spiral — tilting inwards and slightly upwards. The spiral adds structural integrity to the overall igloo.

Pro tips

• Involve your community. Either with the box collection or the building process. They’ll want to have been a part of the magic.
• Good waterproof gloves are essential. With snow-pants on and all the anticipation, we didn’t feel the -25 °C weather.
• Fill the bottom of the igloo with a good layer of snow after. Ice drippings may make it bumpy. Snow makes it soft and comfy again.

Most of all, enjoy every bit of the process as well as the finished product. It won’t last forever.