How big should eaves be?

Eaves are the classic case of form following function. In this podcast I lay out my three key reasons for having them, but a key question is, ‘how big should eaves be?’

This modern house has good sized eaves that are providing some shading, even late in the afternoon.
This modern house has good sized eaves that are providing some shading, even late in the afternoon.
Just a couple of houses along on the same street, this house with no eaves is struggling to protect itself from the sun. This exposure will only get worse, moving into summer.
Just a couple of houses along on the same street, this house with no eaves is struggling to protect itself from the sun. This exposure will only get worse, moving into summer.

Why have eaves?

  1. Radiation – They help shade you and your home from the summer sun, while still allowing light and warmth in during the winter
  2. Precipitation – They protect your house from rain, snow, ice…
  3. Admiration – They look good (in my humble opinion).

How big should eaves be?

While sun charts can look pretty complicated, the good news is that we’ve known about this stuff for a long, long time. We also know about where the sun is going to be a long, long way into the future – at any location on the surface of the planet.

So while there’s no magical, single answer to the question of size, it’s very easy to calculate the optimum size of eaves for your house, in your specific location. Here are a few┬áreferences and resources:

Model your shading

Don’t just calculate the optimum size, there are now plenty of options to demonstrate the impact of decent sized eaves. Lesley England (from episode 78) has this great example…