About Al and Cathlyn Thorwaldson

Thorwaldson  rooftop whole house fans are the world’s first high performance fans of their type. Invented by Kurt Shafer, they pull 8000 CFM with just a 20 inch blade.

Kurt created this web site as a tribute to his father, Al Thorwaldson, and his mother, Cathlyn, both of whom would be proud to see this if they were here.

Al was born about the same time as the home builders “Flat Roof” Smith, Joseph Eichler and Cliff May and would have likely bought a flat roof home in the 50s. His son, Kurt, was born in 1944 and has been inventing things all his life.

Here are Al and Cathlyn in pictures taken about 1940.

Here is a bit of history – Aleph Sigridur Thorwaldson – Born 1882 – Audio File Link:


Aleph’s father was Stigur Thorwaldson and mother was Thorunn Bjornsdottir. She was  Bjorn Thorwaldson’s sister (Bjorn was Kurt’s grandfather) and she was  Al Thorwaldson’s aunt (and Margaret Thorwaldson’s). Margaret married Arch Shafer and they adopted Kurt when Al passed away.