I'm renovating a viking camp into a math creativity center. Lots of fun art jobs to do around the place. One of the doors is in a ratio that is very close to the silver ratio, 1:(√2+1). What's cool about this ratio is that you can cut off two squares from the rectangle and the leftover piece has the same ratio as the original rectangle. That means you can repeat the process again and again.

I designed and made a pattern for this door that shows the ratio. The squares are removed from the ends of the rectangle and the leftover rectangle is in the middle. This is repeated again and again. By inscribing quarter circles in the squares two spirals are made.

My colleague Thomas cut the lines and curves with a router to make grooves, and I painted it with my daughter Maggie.

I have two more doors to decorate with similar designs, so stay tuned...